Merge pull request #26 from kris7t/query-refactor

Query refactor

630 files changed, 10643 insertions, 4969 deletions

diff --git a/subprojects/frontend/.eslintrc.cjs b/subprojects/frontend/.eslintrc.cjs
index 8a7b474a..25b86a83 100644
--- a/subprojects/frontend/.eslintrc.cjs
+++ b/subprojects/frontend/.eslintrc.cjs
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 const path = require('node:path');
 
 // Allow the Codium ESLint plugin to find `tsconfig.json` from the repository root.
@@ -43,6 +49,15 @@ module.exports = {
     // In typescript, some class methods implementing an inderface do not use `this`:
     // https://github.com/typescript-eslint/typescript-eslint/issues/1103
     'class-methods-use-this': 'off',
+    // Disable rules with a high performance cost.
+    // See https://typescript-eslint.io/linting/troubleshooting/performance-troubleshooting/
+    'import/default': 'off',
+    'import/extensions': 'off',
+    'import/named': 'off',
+    'import/namespace': 'off',
+    'import/no-named-as-default': 'off',
+    'import/no-named-as-default-member': 'off',
+    '@typescript-eslint/indent': 'off',
     // Make sure every import can be resolved by `eslint-import-resolver-typescript`.
     'import/no-unresolved': 'error',
     // Organize imports automatically.
@@ -90,6 +105,7 @@ module.exports = {
       files: [
         '.eslintrc.cjs',
         'config/*.ts',
+        'config/*.cjs',
         'prettier.config.cjs',
         'vite.config.ts',
       ],
@@ -103,6 +119,8 @@ module.exports = {
           'error',
           { devDependencies: true },
         ],
+        // Allow writing to the console in ad-hoc scripts.
+        'no-console': 'off',
         // Access to the environment in configuration files.
         'no-process-env': 'off',
       },
diff --git a/subprojects/frontend/assets-src/favicon.svg.license b/subprojects/frontend/assets-src/favicon.svg.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/frontend/assets-src/favicon.svg.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/frontend/assets-src/icon.svg.license b/subprojects/frontend/assets-src/icon.svg.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/frontend/assets-src/icon.svg.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/frontend/assets-src/mask-icon.svg.license b/subprojects/frontend/assets-src/mask-icon.svg.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/frontend/assets-src/mask-icon.svg.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/frontend/build.gradle b/subprojects/frontend/build.gradle
deleted file mode 100644
index 4cc2c5d7..00000000
--- a/subprojects/frontend/build.gradle
+++ /dev/null
@@ -1,131 +0,0 @@
-plugins {
-        id 'refinery-frontend-workspace'
-        id 'refinery-sonarqube'
-}
-
-import org.siouan.frontendgradleplugin.infrastructure.gradle.RunYarn
-
-def viteOutputDir = "${buildDir}/vite"
-def productionResources = file("${viteOutputDir}/production")
-
-frontend {
-        assembleScript = 'run build'
-}
-
-configurations {
-        productionAssets {
-                canBeConsumed = true
-                canBeResolved = false
-        }
-}
-
-def installFrontend = tasks.named('installFrontend')
-
-def sourcesWithoutTypegen = fileTree('src') {
-        exclude '**/*.typegen.ts'
-}
-
-def assembleFrontend = tasks.named('assembleFrontend')
-assembleFrontend.configure {
-        dependsOn generateXStateTypes
-        inputs.dir 'public'
-        inputs.files sourcesWithoutTypegen
-        inputs.file 'index.html'
-        inputs.files('package.json', 'tsconfig.json', 'tsconfig.base.json', 'vite.config.ts')
-        inputs.file rootProject.file('yarn.lock')
-        outputs.dir productionResources
-}
-
-artifacts {
-        productionAssets(productionResources) {
-                builtBy assembleFrontend
-        }
-}
-
-def generateXStateTypes = tasks.register('generateXStateTypes', RunYarn) {
-        dependsOn installFrontend
-        inputs.files sourcesWithoutTypegen
-        inputs.file 'package.json'
-        inputs.file rootProject.file('yarn.lock')
-        outputs.dir 'src'
-        script = 'run typegen'
-        description = 'Generate TypeScript typings for XState state machines.'
-}
-
-def typecheckFrontend = tasks.register('typecheckFrontend', RunYarn) {
-        dependsOn installFrontend
-        dependsOn generateXStateTypes
-        inputs.dir 'src'
-        inputs.dir 'types'
-        inputs.files('package.json', 'tsconfig.json', 'tsconfig.base.json', 'tsconfig.node.json')
-        inputs.file rootProject.file('yarn.lock')
-        outputs.dir "${buildDir}/typescript"
-        script = 'run typecheck'
-        group = 'verification'
-        description = 'Check for TypeScript type errors.'
-}
-
-def lintFrontend = tasks.register('lintFrontend', RunYarn) {
-        dependsOn installFrontend
-        dependsOn generateXStateTypes
-        dependsOn typecheckFrontend
-        inputs.dir 'src'
-        inputs.dir 'types'
-        inputs.files('.eslintrc.cjs', 'prettier.config.cjs')
-        inputs.files('package.json', 'tsconfig.json', 'tsconfig.base.json', 'tsconfig.node.json')
-        inputs.file rootProject.file('yarn.lock')
-        if (project.hasProperty('ci')) {
-                outputs.file "${buildDir}/eslint.json"
-                script = 'run lint:ci'
-        } else {
-                script = 'run lint'
-        }
-        group = 'verification'
-        description = 'Check for TypeScript lint errors and warnings.'
-}
-
-def prettier = tasks.register('fixFrontend', RunYarn) {
-        dependsOn installFrontend
-        dependsOn generateXStateTypes
-        dependsOn typecheckFrontend
-        inputs.dir 'src'
-        inputs.dir 'types'
-        inputs.files('.eslintrc.cjs', 'prettier.config.cjs')
-        inputs.files('package.json', 'tsconfig.json', 'tsconfig.base.json', 'tsconfig.node.json')
-        inputs.file rootProject.file('yarn.lock')
-        script = 'run lint:fix'
-        group = 'verification'
-        description = 'Fix TypeScript lint errors and warnings.'
-}
-
-tasks.named('check') {
-        dependsOn(typecheckFrontend)
-        dependsOn(lintFrontend)
-}
-
-tasks.register('serveFrontend', RunYarn) {
-        dependsOn installFrontend
-        dependsOn generateXStateTypes
-        inputs.dir 'public'
-        inputs.files sourcesWithoutTypegen
-        inputs.file 'index.html'
-        inputs.files('package.json', 'tsconfig.json', 'tsconfig.base.json', 'vite.config.ts')
-        inputs.file rootProject.file('yarn.lock')
-        outputs.dir "${viteOutputDir}/development"
-        script = 'run serve'
-        group = 'run'
-        description = 'Start a Vite dev server with hot module replacement.'
-}
-
-tasks.named('clean') {
-        delete 'dev-dist'
-        delete fileTree('src') {
-                include '**/*.typegen.ts'
-        }
-}
-
-sonarqube.properties {
-        properties['sonar.sources'] = 'src'
-        property 'sonar.nodejs.executable', "${frontend.nodeInstallDirectory.get()}/bin/node"
-        property 'sonar.eslint.reportPaths', "${buildDir}/eslint.json"
-}
diff --git a/subprojects/frontend/build.gradle.kts b/subprojects/frontend/build.gradle.kts
new file mode 100644
index 00000000..d0839371
--- /dev/null
+++ b/subprojects/frontend/build.gradle.kts
@@ -0,0 +1,144 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+import org.siouan.frontendgradleplugin.infrastructure.gradle.RunYarn
+import tools.refinery.gradle.utils.SonarPropertiesUtils
+
+plugins {
+        id("tools.refinery.gradle.frontend-workspace")
+        id("tools.refinery.gradle.sonarqube")
+}
+
+frontend {
+        assembleScript.set("run build")
+}
+
+val viteOutputDir = "$buildDir/vite"
+
+val productionResources = file("$viteOutputDir/production")
+
+val productionAssets: Configuration by configurations.creating {
+        isCanBeConsumed = true
+        isCanBeResolved = false
+}
+
+val sourcesWithoutTypes = fileTree("src") {
+        exclude("**/*.typegen.ts")
+}
+
+val sourcesWithTypes: FileCollection = fileTree("src") + fileTree("types")
+
+val buildScripts: FileCollection = fileTree("config") + files(
+                ".eslintrc.cjs",
+                "prettier.config.cjs",
+                "vite.config.ts",
+)
+
+val installationState = files(
+                rootProject.file("yarn.lock"),
+                rootProject.file("package.json"),
+                "package.json",
+)
+
+val sharedConfigFiles: FileCollection = installationState + files(
+                "tsconfig.json",
+                "tsconfig.base.json",
+                "tsconfig.node.json",
+                "tsconfig.shared.json",
+)
+
+val assembleConfigFiles = sharedConfigFiles + file("vite.config.ts") + fileTree("config") {
+        include("**/*.ts")
+}
+
+val assembleSources = sourcesWithTypes + fileTree("public") + file("index.html")
+
+val assembleFiles = assembleSources + assembleConfigFiles
+
+val lintingFiles: FileCollection = sourcesWithTypes + buildScripts + sharedConfigFiles
+
+tasks {
+        val generateXStateTypes by registering(RunYarn::class) {
+                dependsOn(installFrontend)
+                inputs.files(sourcesWithoutTypes)
+                inputs.files(installationState)
+                outputs.dir("src")
+                script.set("run typegen")
+                description = "Generate TypeScript typings for XState state machines."
+        }
+
+        assembleFrontend {
+                dependsOn(generateXStateTypes)
+                inputs.files(assembleFiles)
+                outputs.dir(productionResources)
+        }
+
+
+        val typeCheckFrontend by registering(RunYarn::class) {
+                dependsOn(installFrontend)
+                dependsOn(generateXStateTypes)
+                inputs.files(lintingFiles)
+                outputs.dir("$buildDir/typescript")
+                script.set("run typecheck")
+                group = "verification"
+                description = "Check for TypeScript type errors."
+        }
+
+        val lintFrontend by registering(RunYarn::class) {
+                dependsOn(installFrontend)
+                dependsOn(generateXStateTypes)
+                dependsOn(typeCheckFrontend)
+                inputs.files(lintingFiles)
+                outputs.file("$buildDir/eslint.json")
+                script.set("run lint")
+                group = "verification"
+                description = "Check for TypeScript lint errors and warnings."
+        }
+
+        register<RunYarn>("fixFrontend") {
+                dependsOn(installFrontend)
+                dependsOn(generateXStateTypes)
+                dependsOn(typeCheckFrontend)
+                inputs.files(lintingFiles)
+                script.set("run lint:fix")
+                group = "verification"
+                description = "Fix TypeScript lint errors and warnings."
+        }
+
+        check {
+                dependsOn(typeCheckFrontend)
+                dependsOn(lintFrontend)
+        }
+
+        register<RunYarn>("serveFrontend") {
+                dependsOn(installFrontend)
+                dependsOn(generateXStateTypes)
+                inputs.files(assembleFiles)
+                outputs.dir("$viteOutputDir/development")
+                script.set("run serve")
+                group = "run"
+                description = "Start a Vite dev server with hot module replacement."
+        }
+
+        clean {
+                delete("dev-dist")
+                delete(fileTree("src") {
+                        include("**/*.typegen.ts")
+                })
+        }
+}
+
+artifacts {
+        add("productionAssets", productionResources) {
+                builtBy(tasks.assembleFrontend)
+        }
+}
+
+sonarqube.properties {
+        SonarPropertiesUtils.addToList(properties, "sonar.sources", "src")
+        property("sonar.nodejs.executable", "${frontend.nodeInstallDirectory.get()}/bin/node")
+        property("sonar.eslint.reportPaths", "$buildDir/eslint.json")
+}
diff --git a/subprojects/frontend/config/backendConfigVitePlugin.ts b/subprojects/frontend/config/backendConfigVitePlugin.ts
index 7a6bc3db..3bffce3a 100644
--- a/subprojects/frontend/config/backendConfigVitePlugin.ts
+++ b/subprojects/frontend/config/backendConfigVitePlugin.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type { PluginOption } from 'vite';
 
 import type BackendConfig from '../src/xtext/BackendConfig';
diff --git a/subprojects/frontend/config/detectDevModeOptions.ts b/subprojects/frontend/config/detectDevModeOptions.ts
index b3696241..665204dc 100644
--- a/subprojects/frontend/config/detectDevModeOptions.ts
+++ b/subprojects/frontend/config/detectDevModeOptions.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type { PluginOption, ServerOptions } from 'vite';
 
 import backendConfigVitePlugin, {
diff --git a/subprojects/frontend/config/eslintReport.cjs b/subprojects/frontend/config/eslintReport.cjs
new file mode 100644
index 00000000..7c4b7bd6
--- /dev/null
+++ b/subprojects/frontend/config/eslintReport.cjs
@@ -0,0 +1,58 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+const { writeFile } = require('node:fs/promises');
+const path = require('node:path');
+const { Readable } = require('node:stream');
+const { pipeline } = require('node:stream/promises');
+
+const { ESLint } = require('eslint');
+
+const rootDir = path.join(__dirname, '..');
+
+/**
+ * Write ESLint report to console.
+ *
+ * @param cli {import('eslint').ESLint} The ESLint CLI.
+ * @param report {import('eslint').ESLint.LintResult[]} The ESLint report.
+ * @return {Promise<void>} A promise that resolves when the report is finished.
+ */
+async function reportToConsole(cli, report) {
+  const stylishFormatter = await cli.loadFormatter('stylish');
+  const output = new Readable();
+  output.push(await stylishFormatter.format(report));
+  output.push(null);
+  return pipeline(output, process.stdout);
+}
+
+/**
+ * Write ESLint report to the <code>build</code> directory.
+ *
+ * @param cli {import('eslint').ESLint} The ESLint CLI.
+ * @param report {import('eslint').ESLint.LintResult[]} The ESLint report.
+ * @return {Promise<void>} A promise that resolves when the report is finished.
+ */
+async function reportToJson(cli, report) {
+  const jsonFormatter = await cli.loadFormatter('json');
+  const json = await jsonFormatter.format(report);
+  const reportPath = path.join(rootDir, 'build', 'eslint.json');
+  return writeFile(reportPath, json, 'utf-8');
+}
+
+async function createReport() {
+  const cli = new ESLint({
+    useEslintrc: true,
+    cwd: rootDir,
+  });
+  const report = await cli.lintFiles('.');
+  await Promise.all([reportToConsole(cli, report), reportToJson(cli, report)]);
+
+  if (report.some((entry) => entry.errorCount > 0)) {
+    process.exitCode = 1;
+  }
+}
+
+createReport().catch(console.error);
diff --git a/subprojects/frontend/config/fetchPackageMetadata.ts b/subprojects/frontend/config/fetchPackageMetadata.ts
index 50807b03..02e16d57 100644
--- a/subprojects/frontend/config/fetchPackageMetadata.ts
+++ b/subprojects/frontend/config/fetchPackageMetadata.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { readFile } from 'node:fs/promises';
 import path from 'node:path';
 
diff --git a/subprojects/frontend/config/manifest.ts b/subprojects/frontend/config/manifest.ts
index 3cec777c..1822dc7c 100644
--- a/subprojects/frontend/config/manifest.ts
+++ b/subprojects/frontend/config/manifest.ts
@@ -1,10 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type { ManifestOptions } from 'vite-plugin-pwa';
 
 const manifest: Partial<ManifestOptions> = {
   lang: 'en-US',
   name: 'Refinery',
   short_name: 'Refinery',
-  description: 'An efficient graph sovler for generating well-formed models',
+  description: 'An efficient graph solver for generating well-formed models',
   theme_color: '#f5f5f5',
   display_override: ['window-controls-overlay'],
   display: 'standalone',
diff --git a/subprojects/frontend/config/minifyHTMLVitePlugin.ts b/subprojects/frontend/config/minifyHTMLVitePlugin.ts
index 18336d4d..7c08c488 100644
--- a/subprojects/frontend/config/minifyHTMLVitePlugin.ts
+++ b/subprojects/frontend/config/minifyHTMLVitePlugin.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { minify, type Options as TerserOptions } from 'html-minifier-terser';
 import type { PluginOption } from 'vite';
 
diff --git a/subprojects/frontend/config/preloadFontsVitePlugin.ts b/subprojects/frontend/config/preloadFontsVitePlugin.ts
index bc6f8eaf..5c04477a 100644
--- a/subprojects/frontend/config/preloadFontsVitePlugin.ts
+++ b/subprojects/frontend/config/preloadFontsVitePlugin.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import micromatch from 'micromatch';
 import type { PluginOption } from 'vite';
 
diff --git a/subprojects/frontend/index.html b/subprojects/frontend/index.html
index 8b6814eb..1bf3472e 100644
--- a/subprojects/frontend/index.html
+++ b/subprojects/frontend/index.html
@@ -1,4 +1,9 @@
 <!DOCTYPE html>
+<!--
+  SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+  SPDX-License-Identifier: EPL-2.0
+-->
 <html lang="en-US">
   <head>
     <meta charset="utf-8">
@@ -13,9 +18,9 @@
     <meta name="theme-color" media="(prefers-color-scheme:light)" content="#f5f5f5">
     <meta name="theme-color" media="(prefers-color-scheme:dark)" content="#21252b">
     <style>
-      @import '@fontsource/inter/variable.css';
-      @import '@fontsource/jetbrains-mono/variable.css';
-      @import '@fontsource/jetbrains-mono/variable-italic.css';
+      @import '@fontsource-variable/inter/wght.css';
+      @import '@fontsource-variable/jetbrains-mono/wght.css';
+      @import '@fontsource-variable/jetbrains-mono/wght-italic.css';
     </style>
   </head>
   <body>
diff --git a/subprojects/frontend/package.json b/subprojects/frontend/package.json
index a761e74c..ba8a0a58 100644
--- a/subprojects/frontend/package.json
+++ b/subprojects/frontend/package.json
@@ -1,4 +1,9 @@
 {
+  "//": [
+    "SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>",
+    "",
+    "SPDX-License-Identifier: EPL-2.0"
+  ],
   "name": "@refinery/frontend",
   "version": "0.0.0",
   "description": "Web frontend for Refinery",
@@ -9,41 +14,40 @@
     "serve": "cross-env MODE=development vite serve",
     "typegen": "xstate typegen \"src/**/*.ts?(x)\"",
     "typecheck": "tsc -p tsconfig.shared.json && tsc -p tsconfig.node.json && tsc -p tsconfig.json",
-    "lint": "eslint .",
-    "lint:ci": "eslint -f json -o build/eslint.json .",
+    "lint": "node config/eslintReport.cjs",
     "lint:fix": "yarn run lint --fix"
   },
   "repository": {
     "type": "git",
     "url": "git+https://github.com/graphs4value/refinery.git"
   },
-  "author": "Refinery authors",
+  "author": "The Refinery Authors <https://refinery.tools/>",
   "license": "EPL-2.0",
   "bugs": {
-    "url": "https://github.com/graphs4value/issues"
+    "url": "https://github.com/graphs4value/refinery/issues"
   },
   "homepage": "https://refinery.tools",
   "dependencies": {
-    "@codemirror/autocomplete": "^6.4.2",
-    "@codemirror/commands": "^6.2.2",
-    "@codemirror/language": "^6.6.0",
-    "@codemirror/lint": "^6.2.0",
-    "@codemirror/search": "^6.3.0",
-    "@codemirror/state": "^6.2.0",
-    "@codemirror/view": "^6.9.3",
-    "@emotion/react": "^11.10.6",
-    "@emotion/styled": "^11.10.6",
-    "@fontsource/inter": "^4.5.15",
-    "@fontsource/jetbrains-mono": "^4.5.12",
-    "@lezer/common": "^1.0.2",
-    "@lezer/highlight": "^1.1.4",
-    "@lezer/lr": "^1.3.3",
+    "@codemirror/autocomplete": "^6.8.0",
+    "@codemirror/commands": "^6.2.4",
+    "@codemirror/language": "^6.8.0",
+    "@codemirror/lint": "^6.2.2",
+    "@codemirror/search": "^6.5.0",
+    "@codemirror/state": "^6.2.1",
+    "@codemirror/view": "^6.13.2",
+    "@emotion/react": "^11.11.1",
+    "@emotion/styled": "^11.11.0",
+    "@fontsource-variable/inter": "^5.0.3",
+    "@fontsource-variable/jetbrains-mono": "^5.0.3",
+    "@lezer/common": "^1.0.3",
+    "@lezer/highlight": "^1.1.6",
+    "@lezer/lr": "^1.3.6",
     "@material-icons/svg": "^1.0.33",
-    "@mui/icons-material": "5.11.11",
-    "@mui/material": "5.11.15",
-    "@vitejs/plugin-react-swc": "^3.2.0",
+    "@mui/icons-material": "5.11.16",
+    "@mui/material": "5.13.5",
+    "@vitejs/plugin-react-swc": "^3.3.2",
     "ansi-styles": "^6.2.1",
-    "csstype": "^3.1.1",
+    "csstype": "^3.1.2",
     "escape-string-regexp": "^5.0.0",
     "lodash-es": "^4.17.21",
     "loglevel": "^1.8.1",
@@ -55,42 +59,41 @@
     "notistack": "^3.0.1",
     "react": "^18.2.0",
     "react-dom": "^18.2.0",
-    "xstate": "^4.37.1",
+    "xstate": "^4.37.2",
     "zod": "^3.21.4"
   },
   "devDependencies": {
-    "@lezer/generator": "^1.2.2",
-    "@tsconfig/strictest": "^2.0.0",
-    "@types/eslint": "^8.37.0",
+    "@lezer/generator": "^1.3.0",
+    "@types/eslint": "^8.40.2",
     "@types/html-minifier-terser": "^7.0.0",
     "@types/lodash-es": "^4.17.7",
     "@types/micromatch": "^4.0.2",
     "@types/ms": "^0.7.31",
-    "@types/node": "^18.15.11",
-    "@types/prettier": "^2.7.2",
-    "@types/react": "^18.0.31",
-    "@types/react-dom": "^18.0.11",
-    "@typescript-eslint/eslint-plugin": "^5.57.0",
-    "@typescript-eslint/parser": "^5.57.0",
-    "@xstate/cli": "^0.4.2",
+    "@types/node": "^18.16.18",
+    "@types/prettier": "^2.7.3",
+    "@types/react": "^18.2.12",
+    "@types/react-dom": "^18.2.5",
+    "@typescript-eslint/eslint-plugin": "^5.59.11",
+    "@typescript-eslint/parser": "^5.59.11",
+    "@xstate/cli": "^0.5.1",
     "cross-env": "^7.0.3",
-    "eslint": "^8.37.0",
+    "eslint": "^8.43.0",
     "eslint-config-airbnb": "^19.0.4",
     "eslint-config-airbnb-typescript": "^17.0.0",
     "eslint-config-prettier": "^8.8.0",
-    "eslint-import-resolver-typescript": "^3.5.4",
+    "eslint-import-resolver-typescript": "^3.5.5",
     "eslint-plugin-import": "^2.27.5",
     "eslint-plugin-jsx-a11y": "^6.7.1",
     "eslint-plugin-mobx": "^0.0.9",
     "eslint-plugin-prettier": "^4.2.1",
     "eslint-plugin-react": "^7.32.2",
     "eslint-plugin-react-hooks": "^4.6.0",
-    "html-minifier-terser": "^7.1.0",
+    "html-minifier-terser": "^7.2.0",
     "micromatch": "^4.0.5",
-    "prettier": "^2.8.7",
-    "typescript": "5.0.3",
-    "vite": "^4.2.1",
-    "vite-plugin-pwa": "^0.14.7",
-    "workbox-window": "^6.5.4"
+    "prettier": "^2.8.8",
+    "typescript": "5.1.3",
+    "vite": "^4.3.9",
+    "vite-plugin-pwa": "^0.16.4",
+    "workbox-window": "^7.0.0"
   }
 }
diff --git a/subprojects/frontend/prettier.config.cjs b/subprojects/frontend/prettier.config.cjs
index 75f5c54d..6f9ff7ad 100644
--- a/subprojects/frontend/prettier.config.cjs
+++ b/subprojects/frontend/prettier.config.cjs
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 /** @type {import('prettier').Config} */
 module.exports = {
   singleQuote: true,
diff --git a/subprojects/frontend/public/apple-touch-icon.png.license b/subprojects/frontend/public/apple-touch-icon.png.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/frontend/public/apple-touch-icon.png.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/frontend/public/favicon-96x96.png.license b/subprojects/frontend/public/favicon-96x96.png.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/frontend/public/favicon-96x96.png.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/frontend/public/favicon.png.license b/subprojects/frontend/public/favicon.png.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/frontend/public/favicon.png.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/frontend/public/favicon.svg.license b/subprojects/frontend/public/favicon.svg.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/frontend/public/favicon.svg.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/frontend/public/icon-192x192.png.license b/subprojects/frontend/public/icon-192x192.png.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/frontend/public/icon-192x192.png.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/frontend/public/icon-512x512.png.license b/subprojects/frontend/public/icon-512x512.png.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/frontend/public/icon-512x512.png.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/frontend/public/icon-any.svg.license b/subprojects/frontend/public/icon-any.svg.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/frontend/public/icon-any.svg.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/frontend/public/mask-icon.svg.license b/subprojects/frontend/public/mask-icon.svg.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/frontend/public/mask-icon.svg.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/frontend/public/robots.txt b/subprojects/frontend/public/robots.txt
index c2a49f4f..e7c73099 100644
--- a/subprojects/frontend/public/robots.txt
+++ b/subprojects/frontend/public/robots.txt
@@ -1,2 +1,6 @@
+# SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+#
+# SPDX-License-Identifier: CC0-1.0
+
 User-agent: *
 Allow: /
diff --git a/subprojects/frontend/src/App.tsx b/subprojects/frontend/src/App.tsx
index cd394345..7f242529 100644
--- a/subprojects/frontend/src/App.tsx
+++ b/subprojects/frontend/src/App.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import Box from '@mui/material/Box';
 import CssBaseline from '@mui/material/CssBaseline';
 import { throttle } from 'lodash-es';
diff --git a/subprojects/frontend/src/Loading.tsx b/subprojects/frontend/src/Loading.tsx
index 489563e0..adee4f0e 100644
--- a/subprojects/frontend/src/Loading.tsx
+++ b/subprojects/frontend/src/Loading.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import CircularProgress from '@mui/material/CircularProgress';
 import { styled } from '@mui/material/styles';
 
diff --git a/subprojects/frontend/src/PWAStore.ts b/subprojects/frontend/src/PWAStore.ts
index e9f99e2a..a1b3ffd9 100644
--- a/subprojects/frontend/src/PWAStore.ts
+++ b/subprojects/frontend/src/PWAStore.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { makeAutoObservable, observable } from 'mobx';
 import ms from 'ms';
 // eslint-disable-next-line import/no-unresolved -- Importing virtual module.
diff --git a/subprojects/frontend/src/Refinery.tsx b/subprojects/frontend/src/Refinery.tsx
index f0162349..b5ff94e1 100644
--- a/subprojects/frontend/src/Refinery.tsx
+++ b/subprojects/frontend/src/Refinery.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import Grow from '@mui/material/Grow';
 import Stack from '@mui/material/Stack';
 import { SnackbarProvider } from 'notistack';
diff --git a/subprojects/frontend/src/RootStore.ts b/subprojects/frontend/src/RootStore.ts
index 2e76d66d..b84c0ce0 100644
--- a/subprojects/frontend/src/RootStore.ts
+++ b/subprojects/frontend/src/RootStore.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { getLogger } from 'loglevel';
 import { makeAutoObservable, runInAction } from 'mobx';
 
diff --git a/subprojects/frontend/src/RootStoreProvider.tsx b/subprojects/frontend/src/RootStoreProvider.tsx
index 2c11a0f9..7cb89af1 100644
--- a/subprojects/frontend/src/RootStoreProvider.tsx
+++ b/subprojects/frontend/src/RootStoreProvider.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { type ReactNode, createContext, useContext } from 'react';
 
 import type RootStore from './RootStore';
diff --git a/subprojects/frontend/src/ToggleDarkModeButton.tsx b/subprojects/frontend/src/ToggleDarkModeButton.tsx
index 59714f20..7a835e61 100644
--- a/subprojects/frontend/src/ToggleDarkModeButton.tsx
+++ b/subprojects/frontend/src/ToggleDarkModeButton.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import DarkModeIcon from '@mui/icons-material/DarkMode';
 import LightModeIcon from '@mui/icons-material/LightMode';
 import IconButton from '@mui/material/IconButton';
diff --git a/subprojects/frontend/src/TopBar.tsx b/subprojects/frontend/src/TopBar.tsx
index 5a825512..f2542b14 100644
--- a/subprojects/frontend/src/TopBar.tsx
+++ b/subprojects/frontend/src/TopBar.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import GitHubIcon from '@mui/icons-material/GitHub';
 import AppBar from '@mui/material/AppBar';
 import Button from '@mui/material/Button';
diff --git a/subprojects/frontend/src/UpdateNotification.tsx b/subprojects/frontend/src/UpdateNotification.tsx
index 5c8c2d01..d86c0703 100644
--- a/subprojects/frontend/src/UpdateNotification.tsx
+++ b/subprojects/frontend/src/UpdateNotification.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import Button from '@mui/material/Button';
 import { observer } from 'mobx-react-lite';
 import { useEffect } from 'react';
diff --git a/subprojects/frontend/src/WindowControlsOverlayColor.tsx b/subprojects/frontend/src/WindowControlsOverlayColor.tsx
index 14eda566..cfa468ea 100644
--- a/subprojects/frontend/src/WindowControlsOverlayColor.tsx
+++ b/subprojects/frontend/src/WindowControlsOverlayColor.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { useTheme } from '@mui/material/styles';
 import { useEffect } from 'react';
 
diff --git a/subprojects/frontend/src/editor/AnimatedButton.tsx b/subprojects/frontend/src/editor/AnimatedButton.tsx
index f75d4617..dbbda618 100644
--- a/subprojects/frontend/src/editor/AnimatedButton.tsx
+++ b/subprojects/frontend/src/editor/AnimatedButton.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import Box from '@mui/material/Box';
 import Button from '@mui/material/Button';
 import { styled, type SxProps, type Theme } from '@mui/material/styles';
diff --git a/subprojects/frontend/src/editor/ConnectButton.tsx b/subprojects/frontend/src/editor/ConnectButton.tsx
index e2d251f3..eed6fbc7 100644
--- a/subprojects/frontend/src/editor/ConnectButton.tsx
+++ b/subprojects/frontend/src/editor/ConnectButton.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import CloudIcon from '@mui/icons-material/Cloud';
 import CloudOffIcon from '@mui/icons-material/CloudOff';
 import SyncIcon from '@mui/icons-material/Sync';
diff --git a/subprojects/frontend/src/editor/ConnectionStatusNotification.tsx b/subprojects/frontend/src/editor/ConnectionStatusNotification.tsx
index 9b27f45c..b7b962ab 100644
--- a/subprojects/frontend/src/editor/ConnectionStatusNotification.tsx
+++ b/subprojects/frontend/src/editor/ConnectionStatusNotification.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import Button from '@mui/material/Button';
 import { observer } from 'mobx-react-lite';
 import { useEffect } from 'react';
diff --git a/subprojects/frontend/src/editor/DiagnosticValue.ts b/subprojects/frontend/src/editor/DiagnosticValue.ts
index b4e0b165..20478262 100644
--- a/subprojects/frontend/src/editor/DiagnosticValue.ts
+++ b/subprojects/frontend/src/editor/DiagnosticValue.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type { Diagnostic } from '@codemirror/lint';
 import { RangeValue } from '@codemirror/state';
 
diff --git a/subprojects/frontend/src/editor/EditorArea.tsx b/subprojects/frontend/src/editor/EditorArea.tsx
index cfb988b2..905fa2ec 100644
--- a/subprojects/frontend/src/editor/EditorArea.tsx
+++ b/subprojects/frontend/src/editor/EditorArea.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import Box from '@mui/material/Box';
 import { useTheme } from '@mui/material/styles';
 import { observer } from 'mobx-react-lite';
diff --git a/subprojects/frontend/src/editor/EditorButtons.tsx b/subprojects/frontend/src/editor/EditorButtons.tsx
index 53b06e23..9b187e5c 100644
--- a/subprojects/frontend/src/editor/EditorButtons.tsx
+++ b/subprojects/frontend/src/editor/EditorButtons.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type { Diagnostic } from '@codemirror/lint';
 import CheckIcon from '@mui/icons-material/Check';
 import ErrorIcon from '@mui/icons-material/Error';
diff --git a/subprojects/frontend/src/editor/EditorPane.tsx b/subprojects/frontend/src/editor/EditorPane.tsx
index f7f8241a..87f408fe 100644
--- a/subprojects/frontend/src/editor/EditorPane.tsx
+++ b/subprojects/frontend/src/editor/EditorPane.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import Box from '@mui/material/Box';
 import Skeleton from '@mui/material/Skeleton';
 import Stack from '@mui/material/Stack';
diff --git a/subprojects/frontend/src/editor/EditorStore.ts b/subprojects/frontend/src/editor/EditorStore.ts
index 0a0d885d..b98f085e 100644
--- a/subprojects/frontend/src/editor/EditorStore.ts
+++ b/subprojects/frontend/src/editor/EditorStore.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type {
   CompletionContext,
   CompletionResult,
diff --git a/subprojects/frontend/src/editor/EditorTheme.ts b/subprojects/frontend/src/editor/EditorTheme.ts
index 01b65a7e..e057ce18 100644
--- a/subprojects/frontend/src/editor/EditorTheme.ts
+++ b/subprojects/frontend/src/editor/EditorTheme.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import errorSVG from '@material-icons/svg/svg/error/baseline.svg?raw';
 import expandMoreSVG from '@material-icons/svg/svg/expand_more/baseline.svg?raw';
 import infoSVG from '@material-icons/svg/svg/info/baseline.svg?raw';
@@ -8,32 +14,6 @@ function svgURL(svg: string): string {
   return `url('data:image/svg+xml;utf8,${svg}')`;
 }
 
-function radialShadowTheme(
-  origin: string,
-  scaleX: boolean,
-  scaleY: boolean,
-): CSSObject {
-  function radialGradient(opacity: number, scale: string): string {
-    return `radial-gradient(
-        farthest-side at ${origin},
-        rgba(0, 0, 0, ${opacity}),
-        rgba(0, 0, 0, 0)
-      )
-      ${origin} /
-      ${scaleX ? scale : '100%'}
-      ${scaleY ? scale : '100%'}
-      no-repeat`;
-  }
-
-  return {
-    background: `
-      ${radialGradient(0.2, '40%')},
-      ${radialGradient(0.14, '50%')},
-      ${radialGradient(0.12, '100%')}
-    `,
-  };
-}
-
 export default styled('div', {
   name: 'EditorTheme',
   shouldForwardProp: (propName) =>
@@ -52,98 +32,13 @@ export default styled('div', {
     },
   };
 
-  const scrollerThumbOpacity = theme.palette.mode === 'dark' ? 0.16 : 0.28;
-
   const generalStyle: CSSObject = {
     background: theme.palette.background.default,
     '&, .cm-editor': {
       height: '100%',
     },
-    '.cm-scroller-holder': {
-      display: 'flex',
-      position: 'relative',
-      flexDirection: 'column',
-      overflow: 'hidden',
-      flex: '1 1',
-    },
-    '.cm-scroller-spacer': {
-      position: 'sticky',
-      flexShrink: 0,
-      zIndex: 300,
-      width: 1,
-      marginRight: -1,
-      pointerEvents: 'none',
-    },
     '.cm-scroller': {
       color: theme.palette.text.secondary,
-      scrollbarWidth: 'none',
-      MsOverflowStyle: 'none',
-      '&::-webkit-scrollbar': {
-        width: 0,
-        height: 0,
-        background: 'transparent',
-      },
-    },
-    '.cm-scroller-track': {
-      position: 'absolute',
-      zIndex: 300,
-      touchAction: 'none',
-    },
-    '.cm-scroller-thumb': {
-      position: 'absolute',
-      background: theme.palette.text.secondary,
-      opacity: scrollerThumbOpacity,
-      transition: theme.transitions.create('opacity', {
-        duration: theme.transitions.duration.shortest,
-      }),
-      touchAction: 'none',
-      WebkitTapHighlightColor: 'transparent',
-      '&:hover': {
-        opacity: 0.75,
-        '@media (hover: none)': {
-          opacity: scrollerThumbOpacity,
-        },
-      },
-      '&.active': {
-        opacity: 1,
-        pointerEvents: 'none',
-        userSelect: 'none',
-      },
-    },
-    '.cm-scroller-track-y, .cm-scroller-thumb-y': {
-      top: 0,
-      right: 0,
-      width: 12,
-    },
-    '.cm-scroller-track-x, .cm-scroller-thumb-x': {
-      left: 0,
-      bottom: 0,
-      height: 12,
-    },
-    '.cm-scroller-track-x': {
-      right: 12,
-    },
-    '.cm-scroller-gutter-decoration': {
-      position: 'absolute',
-      top: 0,
-      bottom: 0,
-      left: 0,
-      width: 0,
-      transition: theme.transitions.create('width', {
-        duration: theme.transitions.duration.shortest,
-      }),
-      ...radialShadowTheme('0 50%', true, false),
-    },
-    '.cm-scroller-top-decoration': {
-      position: 'absolute',
-      top: 0,
-      left: 0,
-      right: 0,
-      height: 0,
-      transition: theme.transitions.create('height', {
-        duration: theme.transitions.duration.shortest,
-      }),
-      ...radialShadowTheme('50% 0', false, true),
     },
     '.cm-gutters': {
       background: theme.palette.background.default,
@@ -162,7 +57,6 @@ export default styled('div', {
       background: 'transparent',
     },
     '.cm-cursor, .cm-cursor-primary': {
-      marginLeft: -1,
       borderLeft: `2px solid ${theme.palette.info.main}`,
     },
     '.cm-selectionBackground': {
@@ -175,7 +69,6 @@ export default styled('div', {
       },
     },
     '.cm-line': {
-      position: 'relative', // For indentation highlights
       padding: '0 12px 0 0px',
     },
   };
@@ -265,13 +158,6 @@ export default styled('div', {
     '.cm-searchMatch-selected': {
       background: theme.palette.highlight.search.selected,
     },
-    '.cm-indentation-marker': {
-      display: 'inline-block',
-      boxShadow: `1px 0 0 ${theme.palette.text.disabled} inset`,
-      '&.active': {
-        boxShadow: `1px 0 0 ${theme.palette.text.primary} inset`,
-      },
-    },
     '.cm-scroller-selection': {
       position: 'absolute',
       right: 0,
@@ -452,11 +338,11 @@ export default styled('div', {
 
   const foldStyle = {
     '.cm-foldGutter': {
-      width: 17,
+      width: 16,
     },
     '.problem-editor-foldMarker': {
       display: 'block',
-      margin: '4px 1px 4px 0',
+      margin: '4px 0 4px 0',
       padding: 0,
       maskImage: svgURL(expandMoreSVG),
       maskSize: '16px 16px',
@@ -467,7 +353,7 @@ export default styled('div', {
       cursor: 'pointer',
       WebkitTapHighlightColor: 'transparent',
       [theme.breakpoints.down('sm')]: {
-        margin: '2px 1px 2px 0',
+        margin: '2px 0 2px 0',
       },
     },
     '.problem-editor-foldMarker-open': {
diff --git a/subprojects/frontend/src/editor/GenerateButton.tsx b/subprojects/frontend/src/editor/GenerateButton.tsx
index 2036fc28..3837ef8e 100644
--- a/subprojects/frontend/src/editor/GenerateButton.tsx
+++ b/subprojects/frontend/src/editor/GenerateButton.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import DangerousOutlinedIcon from '@mui/icons-material/DangerousOutlined';
 import PlayArrowIcon from '@mui/icons-material/PlayArrow';
 import Button from '@mui/material/Button';
diff --git a/subprojects/frontend/src/editor/LintPanelStore.ts b/subprojects/frontend/src/editor/LintPanelStore.ts
index 502f9c59..f81587fa 100644
--- a/subprojects/frontend/src/editor/LintPanelStore.ts
+++ b/subprojects/frontend/src/editor/LintPanelStore.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { closeLintPanel, openLintPanel } from '@codemirror/lint';
 
 import type EditorStore from './EditorStore';
diff --git a/subprojects/frontend/src/editor/PanelStore.ts b/subprojects/frontend/src/editor/PanelStore.ts
index 4f827280..25ef8b6c 100644
--- a/subprojects/frontend/src/editor/PanelStore.ts
+++ b/subprojects/frontend/src/editor/PanelStore.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type { Command } from '@codemirror/view';
 import { action, makeObservable, observable } from 'mobx';
 
diff --git a/subprojects/frontend/src/editor/SearchPanel.ts b/subprojects/frontend/src/editor/SearchPanel.ts
index c9df41b7..b63d5eed 100644
--- a/subprojects/frontend/src/editor/SearchPanel.ts
+++ b/subprojects/frontend/src/editor/SearchPanel.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import {
   type EditorView,
   type Panel,
diff --git a/subprojects/frontend/src/editor/SearchPanelPortal.tsx b/subprojects/frontend/src/editor/SearchPanelPortal.tsx
index 5cf1c90e..b4b07c74 100644
--- a/subprojects/frontend/src/editor/SearchPanelPortal.tsx
+++ b/subprojects/frontend/src/editor/SearchPanelPortal.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import Portal from '@mui/material/Portal';
 import { observer } from 'mobx-react-lite';
 
diff --git a/subprojects/frontend/src/editor/SearchPanelStore.ts b/subprojects/frontend/src/editor/SearchPanelStore.ts
index 65d595a8..6a97baf1 100644
--- a/subprojects/frontend/src/editor/SearchPanelStore.ts
+++ b/subprojects/frontend/src/editor/SearchPanelStore.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import {
   closeSearchPanel,
   findNext,
diff --git a/subprojects/frontend/src/editor/SearchToolbar.tsx b/subprojects/frontend/src/editor/SearchToolbar.tsx
index 54f3dba7..4ae7e893 100644
--- a/subprojects/frontend/src/editor/SearchToolbar.tsx
+++ b/subprojects/frontend/src/editor/SearchToolbar.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import CloseIcon from '@mui/icons-material/Close';
 import FindReplaceIcon from '@mui/icons-material/FindReplace';
 import KeyboardArrowDownIcon from '@mui/icons-material/KeyboardArrowDown';
diff --git a/subprojects/frontend/src/editor/createEditorState.ts b/subprojects/frontend/src/editor/createEditorState.ts
index ce1efa4f..67b8fb9e 100644
--- a/subprojects/frontend/src/editor/createEditorState.ts
+++ b/subprojects/frontend/src/editor/createEditorState.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import {
   closeBrackets,
   closeBracketsKeymap,
@@ -38,8 +44,6 @@ import type EditorStore from './EditorStore';
 import SearchPanel from './SearchPanel';
 import exposeDiagnostics from './exposeDiagnostics';
 import findOccurrences from './findOccurrences';
-import indentationMarkerViewPlugin from './indentationMarkerViewPlugin';
-import scrollbarViewPlugin from './scrollbarViewPlugin';
 import semanticHighlighting from './semanticHighlighting';
 
 export default function createEditorState(
@@ -64,7 +68,6 @@ export default function createEditorState(
       highlightSpecialChars(),
       history(),
       indentOnInput(),
-      indentationMarkerViewPlugin(),
       rectangularSelection(),
       search({
         createPanel(view) {
@@ -123,7 +126,6 @@ export default function createEditorState(
         ...defaultKeymap,
       ]),
       problemLanguageSupport(),
-      scrollbarViewPlugin(store),
     ],
   });
 }
diff --git a/subprojects/frontend/src/editor/defineDecorationSetExtension.ts b/subprojects/frontend/src/editor/defineDecorationSetExtension.ts
index d9c7bc7d..0887c92e 100644
--- a/subprojects/frontend/src/editor/defineDecorationSetExtension.ts
+++ b/subprojects/frontend/src/editor/defineDecorationSetExtension.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { StateEffect, StateField, TransactionSpec } from '@codemirror/state';
 import { EditorView, Decoration, DecorationSet } from '@codemirror/view';
 
diff --git a/subprojects/frontend/src/editor/exposeDiagnostics.ts b/subprojects/frontend/src/editor/exposeDiagnostics.ts
index 82f24c93..c4dcbb87 100644
--- a/subprojects/frontend/src/editor/exposeDiagnostics.ts
+++ b/subprojects/frontend/src/editor/exposeDiagnostics.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { setDiagnosticsEffect } from '@codemirror/lint';
 import {
   StateField,
diff --git a/subprojects/frontend/src/editor/findOccurrences.ts b/subprojects/frontend/src/editor/findOccurrences.ts
index 08c078c2..00dffc96 100644
--- a/subprojects/frontend/src/editor/findOccurrences.ts
+++ b/subprojects/frontend/src/editor/findOccurrences.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import {
   type Range,
   RangeSet,
diff --git a/subprojects/frontend/src/editor/indentationMarkerViewPlugin.ts b/subprojects/frontend/src/editor/indentationMarkerViewPlugin.ts
deleted file mode 100644
index 730fa6e3..00000000
--- a/subprojects/frontend/src/editor/indentationMarkerViewPlugin.ts
+++ /dev/null
@@ -1,341 +0,0 @@
-/**
- * @file CodeMirror plugin to highlight indentation
- *
- * This file is based on the
- * [@replit/codemirror-indentation-markers](https://github.com/replit/codemirror-indentation-markers)
- * package, which is available under the
- * [MIT License](https://github.com/replit/codemirror-indentation-markers/blob/543cc508ca5cef5d8350af23973eb1425e31525c/LICENSE).
- *
- * The highlighting heuristics were adjusted to make them more suitable
- * for logic programming.
- *
- * @see https://github.com/replit/codemirror-indentation-markers/blob/543cc508ca5cef5d8350af23973eb1425e31525c/src/index.ts
- */
-
-import { getIndentUnit } from '@codemirror/language';
-import { Text, RangeSet, EditorState } from '@codemirror/state';
-import {
-  ViewPlugin,
-  Decoration,
-  EditorView,
-  WidgetType,
-  PluginValue,
-} from '@codemirror/view';
-
-export const INDENTATION_MARKER_CLASS = 'cm-indentation-marker';
-
-export const INDENTATION_MARKER_ACTIVE_CLASS = 'active';
-
-const indentationMark = Decoration.mark({
-  class: INDENTATION_MARKER_CLASS,
-  tagName: 'span',
-});
-
-const activeIndentationMark = Decoration.mark({
-  class: `${INDENTATION_MARKER_CLASS} ${INDENTATION_MARKER_ACTIVE_CLASS}`,
-  tagName: 'span',
-});
-
-/**
- * Widget used to simulate N indentation markers on empty lines.
- */
-class IndentationWidget extends WidgetType {
-  constructor(
-    readonly numIndent: number,
-    readonly indentSize: number,
-    readonly activeIndent?: number,
-  ) {
-    super();
-  }
-
-  override eq(other: IndentationWidget) {
-    return (
-      this.numIndent === other.numIndent &&
-      this.indentSize === other.indentSize &&
-      this.activeIndent === other.activeIndent
-    );
-  }
-
-  override toDOM(view: EditorView) {
-    const indentSize = getIndentUnit(view.state);
-
-    const wrapper = document.createElement('span');
-    wrapper.style.top = '0';
-    wrapper.style.left = '0';
-    wrapper.style.position = 'absolute';
-    wrapper.style.pointerEvents = 'none';
-
-    for (let indent = 0; indent < this.numIndent; indent += 1) {
-      const element = document.createElement('span');
-      element.className = INDENTATION_MARKER_CLASS;
-      element.classList.toggle(
-        INDENTATION_MARKER_ACTIVE_CLASS,
-        indent === this.activeIndent,
-      );
-      element.innerHTML = ' '.repeat(indentSize);
-      wrapper.appendChild(element);
-    }
-
-    return wrapper;
-  }
-}
-
-/**
- * Returns the number of indentation markers a non-empty line should have
- * based on the text in the line and the size of the indent.
- */
-function getNumIndentMarkersForNonEmptyLine(
-  text: string,
-  indentSize: number,
-  onIndentMarker?: (pos: number) => void,
-) {
-  let numIndents = 0;
-  let numConsecutiveSpaces = 0;
-  let prevChar: string | undefined;
-
-  for (let char = 0; char < text.length; char += 1) {
-    // Bail if we encounter a non-whitespace character
-    if (text[char] !== ' ' && text[char] !== '\t') {
-      // We still increment the indentation level if we would
-      // have added a marker here had this been a space or tab.
-      if (numConsecutiveSpaces % indentSize === 0 && char !== 0) {
-        numIndents += 1;
-      }
-
-      return numIndents;
-    }
-
-    // Every tab and N space has an indentation marker
-    const shouldAddIndent =
-      prevChar === '\t' || numConsecutiveSpaces % indentSize === 0;
-
-    if (shouldAddIndent) {
-      numIndents += 1;
-
-      if (onIndentMarker) {
-        onIndentMarker(char);
-      }
-    }
-
-    if (text[char] === ' ') {
-      numConsecutiveSpaces += 1;
-    } else {
-      numConsecutiveSpaces = 0;
-    }
-
-    prevChar = text[char];
-  }
-
-  return numIndents;
-}
-
-/**
- * Returns the number of indent markers an empty line should have
- * based on the number of indent markers of the previous
- * and next non-empty lines.
- */
-function getNumIndentMarkersForEmptyLine(prev: number, next: number) {
-  const min = Math.min(prev, next);
-  const max = Math.max(prev, next);
-
-  // If only one side is non-zero, we omit markers,
-  // because in logic programming, a block often ends with an empty line.
-  if (min === 0 && max > 0) {
-    return 0;
-  }
-
-  // Else, default to the minimum of the two
-  return min;
-}
-
-/**
- * Returns the next non-empty line and its indent level.
- */
-function findNextNonEmptyLineAndIndentLevel(
-  doc: Text,
-  startLine: number,
-  indentSize: number,
-): [number, number] {
-  const numLines = doc.lines;
-  let lineNo = startLine;
-
-  while (lineNo <= numLines) {
-    const { text } = doc.line(lineNo);
-
-    if (text.trim().length === 0) {
-      lineNo += 1;
-    } else {
-      const indent = getNumIndentMarkersForNonEmptyLine(text, indentSize);
-      return [lineNo, indent];
-    }
-  }
-
-  // Reached the end of the doc
-  return [numLines + 1, 0];
-}
-
-interface IndentationMarkerDesc {
-  lineNumber: number;
-  from: number;
-  to: number;
-  create(activeIndentIndex?: number): Decoration;
-}
-
-/**
- * Returns a range of lines with an active indent marker.
- */
-function getLinesWithActiveIndentMarker(
-  state: EditorState,
-  indentMap: Map<number, number>,
-): { start: number; end: number; activeIndent: number } {
-  const currentLine = state.doc.lineAt(state.selection.main.head);
-  const currentIndent = indentMap.get(currentLine.number);
-  const currentLineNo = currentLine.number;
-
-  if (!currentIndent) {
-    return { start: -1, end: -1, activeIndent: NaN };
-  }
-
-  let start: number;
-  let end: number;
-
-  for (start = currentLineNo; start >= 0; start -= 1) {
-    const indent = indentMap.get(start - 1);
-    if (!indent || indent < currentIndent) {
-      break;
-    }
-  }
-
-  for (end = currentLineNo; ; end += 1) {
-    const indent = indentMap.get(end + 1);
-    if (!indent || indent < currentIndent) {
-      break;
-    }
-  }
-
-  return { start, end, activeIndent: currentIndent };
-}
-/**
- * Adds indentation markers to all lines within view.
- */
-function addIndentationMarkers(view: EditorView) {
-  const indentSize = getIndentUnit(view.state);
-  const indentSizeMap = new Map</* lineNumber */ number, number>();
-  const decorations: Array<IndentationMarkerDesc> = [];
-
-  view.visibleRanges.forEach(({ from, to }) => {
-    let pos = from;
-
-    let prevIndentMarkers = 0;
-    let nextIndentMarkers = 0;
-    let nextNonEmptyLine = 0;
-
-    while (pos <= to) {
-      const line = view.state.doc.lineAt(pos);
-      const { text } = line;
-
-      // If a line is empty, we match the indentation according
-      // to a heuristic based on the indentations of the
-      // previous and next non-empty lines.
-      if (text.trim().length === 0) {
-        // To retrieve the next non-empty indentation level,
-        // we perform a lookahead and cache the result.
-        if (nextNonEmptyLine < line.number) {
-          const [nextLine, nextIndent] = findNextNonEmptyLineAndIndentLevel(
-            view.state.doc,
-            line.number + 1,
-            indentSize,
-          );
-
-          nextNonEmptyLine = nextLine;
-          nextIndentMarkers = nextIndent;
-        }
-
-        const numIndentMarkers = getNumIndentMarkersForEmptyLine(
-          prevIndentMarkers,
-          nextIndentMarkers,
-        );
-
-        // Add the indent widget and move on to next line
-        indentSizeMap.set(line.number, numIndentMarkers);
-        decorations.push({
-          from: pos,
-          to: pos,
-          lineNumber: line.number,
-          create: (activeIndentIndex) =>
-            Decoration.widget({
-              widget: new IndentationWidget(
-                numIndentMarkers,
-                indentSize,
-                activeIndentIndex,
-              ),
-            }),
-        });
-      } else {
-        const indices: Array<number> = [];
-
-        prevIndentMarkers = getNumIndentMarkersForNonEmptyLine(
-          text,
-          indentSize,
-          (char) => indices.push(char),
-        );
-
-        indentSizeMap.set(line.number, indices.length);
-        decorations.push(
-          ...indices.map(
-            (char, i): IndentationMarkerDesc => ({
-              from: line.from + char,
-              to: line.from + char + 1,
-              lineNumber: line.number,
-              create: (activeIndentIndex) =>
-                activeIndentIndex === i
-                  ? activeIndentationMark
-                  : indentationMark,
-            }),
-          ),
-        );
-      }
-
-      // Move on to the next line
-      pos = line.to + 1;
-    }
-  });
-
-  const activeBlockRange = getLinesWithActiveIndentMarker(
-    view.state,
-    indentSizeMap,
-  );
-
-  return RangeSet.of<Decoration>(
-    Array.from(decorations).map(({ lineNumber, from, to, create }) => {
-      const activeIndent =
-        lineNumber >= activeBlockRange.start &&
-        lineNumber <= activeBlockRange.end
-          ? activeBlockRange.activeIndent - 1
-          : undefined;
-
-      return { from, to, value: create(activeIndent) };
-    }),
-    true,
-  );
-}
-
-export default function indentationMarkerViewPlugin() {
-  return ViewPlugin.define<PluginValue & { decorations: RangeSet<Decoration> }>(
-    (view) => ({
-      decorations: addIndentationMarkers(view),
-      update(update) {
-        if (
-          update.docChanged ||
-          update.viewportChanged ||
-          update.selectionSet
-        ) {
-          this.decorations = addIndentationMarkers(update.view);
-        }
-      },
-    }),
-    {
-      decorations: (v) => v.decorations,
-    },
-  );
-}
diff --git a/subprojects/frontend/src/editor/scrollbarViewPlugin.ts b/subprojects/frontend/src/editor/scrollbarViewPlugin.ts
deleted file mode 100644
index f44034fd..00000000
--- a/subprojects/frontend/src/editor/scrollbarViewPlugin.ts
+++ /dev/null
@@ -1,357 +0,0 @@
-import { EditorSelection } from '@codemirror/state';
-import {
-  type EditorView,
-  type PluginValue,
-  ViewPlugin,
-} from '@codemirror/view';
-import { reaction } from 'mobx';
-
-import type EditorStore from './EditorStore';
-import { getDiagnostics } from './exposeDiagnostics';
-import findOccurrences from './findOccurrences';
-
-export const HOLDER_CLASS = 'cm-scroller-holder';
-export const SPACER_CLASS = 'cm-scroller-spacer';
-export const TRACK_CLASS = 'cm-scroller-track';
-export const THUMB_CLASS = 'cm-scroller-thumb';
-export const THUMB_ACTIVE_CLASS = 'active';
-export const GUTTER_DECORATION_CLASS = 'cm-scroller-gutter-decoration';
-export const TOP_DECORATION_CLASS = 'cm-scroller-top-decoration';
-export const ANNOTATION_SELECTION_CLASS = 'cm-scroller-selection';
-export const ANNOTATION_DIAGNOSTIC_CLASS = 'cm-scroller-diagnostic';
-export const ANNOTATION_OCCURRENCE_CLASS = 'cm-scroller-occurrence';
-export const SHADOW_WIDTH = 10;
-export const SCROLLBAR_WIDTH = 12;
-export const ANNOTATION_WIDTH = SCROLLBAR_WIDTH / 2;
-export const MIN_ANNOTATION_HEIGHT = 1;
-
-function createScrollbar(
-  holder: HTMLElement,
-  direction: 'x' | 'y',
-  touchCallback: (offsetX: number, offsetY: number) => void,
-  moveCallback: (movementX: number, movementY: number) => void,
-): { track: HTMLElement; thumb: HTMLElement } {
-  const track = holder.ownerDocument.createElement('div');
-  track.className = `${TRACK_CLASS} ${TRACK_CLASS}-${direction}`;
-  holder.appendChild(track);
-
-  const thumb = holder.ownerDocument.createElement('div');
-  thumb.className = `${THUMB_CLASS} ${THUMB_CLASS}-${direction}`;
-  track.appendChild(thumb);
-
-  let pointerId: number | undefined;
-  track.addEventListener('pointerdown', (event) => {
-    if (pointerId !== undefined) {
-      event.preventDefault();
-      return;
-    }
-    ({ pointerId } = event);
-    thumb.classList.add(THUMB_ACTIVE_CLASS);
-    if (event.target === thumb) {
-      // Prevent implicit pointer capture on mobile.
-      thumb.releasePointerCapture(pointerId);
-    } else {
-      touchCallback(event.offsetX, event.offsetY);
-    }
-    track.setPointerCapture(pointerId);
-  });
-
-  track.addEventListener('pointermove', (event) => {
-    if (event.pointerId !== pointerId) {
-      return;
-    }
-    moveCallback(event.movementX, event.movementY);
-    event.preventDefault();
-  });
-
-  function scrollEnd(event: PointerEvent) {
-    if (event.pointerId !== pointerId) {
-      return;
-    }
-    pointerId = undefined;
-    thumb.classList.remove(THUMB_ACTIVE_CLASS);
-  }
-
-  track.addEventListener('pointerup', scrollEnd, { passive: true });
-  track.addEventListener('pointercancel', scrollEnd, { passive: true });
-
-  return { track, thumb };
-}
-
-function rebuildAnnotations(
-  view: EditorView,
-  scrollHeight: number,
-  trackYHeight: number,
-  holder: HTMLElement,
-  annotations: HTMLDivElement[],
-) {
-  const { state } = view;
-  const overlayAnnotationsHeight =
-    (view.contentHeight / scrollHeight) * trackYHeight;
-  const lineHeight = overlayAnnotationsHeight / state.doc.lines;
-
-  let i = 0;
-
-  function getOrCreateAnnotation(from: number, to?: number): HTMLDivElement {
-    const startLine = state.doc.lineAt(from).number;
-    const endLine = to === undefined ? startLine : state.doc.lineAt(to).number;
-    const top = (startLine - 1) * lineHeight;
-    const height = Math.max(
-      MIN_ANNOTATION_HEIGHT,
-      Math.max(1, endLine - startLine) * lineHeight,
-    );
-
-    let annotation: HTMLDivElement | undefined;
-    if (i < annotations.length) {
-      annotation = annotations[i];
-    }
-    if (annotation === undefined) {
-      annotation = holder.ownerDocument.createElement('div');
-      annotations.push(annotation);
-      holder.appendChild(annotation);
-    }
-    i += 1;
-
-    annotation.style.top = `${top}px`;
-    annotation.style.height = `${height}px`;
-
-    return annotation;
-  }
-
-  state.selection.ranges.forEach(({ head }) => {
-    const selectionAnnotation = getOrCreateAnnotation(head);
-    selectionAnnotation.className = ANNOTATION_SELECTION_CLASS;
-    selectionAnnotation.style.width = `${SCROLLBAR_WIDTH}px`;
-  });
-
-  const diagnosticsIter = getDiagnostics(state).iter();
-  while (diagnosticsIter.value !== null) {
-    const diagnosticAnnotation = getOrCreateAnnotation(
-      diagnosticsIter.from,
-      diagnosticsIter.to,
-    );
-    diagnosticAnnotation.className = `${ANNOTATION_DIAGNOSTIC_CLASS} ${ANNOTATION_DIAGNOSTIC_CLASS}-${diagnosticsIter.value.severity}`;
-    diagnosticAnnotation.style.width = `${ANNOTATION_WIDTH}px`;
-    diagnosticsIter.next();
-  }
-
-  const occurrences = view.state.field(findOccurrences);
-  const occurrencesIter = occurrences.iter();
-  while (occurrencesIter.value !== null) {
-    const occurrenceAnnotation = getOrCreateAnnotation(
-      occurrencesIter.from,
-      occurrencesIter.to,
-    );
-    occurrenceAnnotation.className = ANNOTATION_OCCURRENCE_CLASS;
-    occurrenceAnnotation.style.width = `${ANNOTATION_WIDTH}px`;
-    occurrenceAnnotation.style.right = `${ANNOTATION_WIDTH}px`;
-    occurrencesIter.next();
-  }
-
-  annotations
-    .splice(i)
-    .forEach((staleAnnotation) => holder.removeChild(staleAnnotation));
-}
-
-export default function scrollbarViewPlugin(
-  editorStore: EditorStore,
-): ViewPlugin<PluginValue> {
-  return ViewPlugin.define((view) => {
-    const { scrollDOM } = view;
-    const { ownerDocument, parentElement: parentDOM } = scrollDOM;
-    if (parentDOM === null) {
-      return {};
-    }
-
-    const holder = ownerDocument.createElement('div');
-    holder.className = HOLDER_CLASS;
-    parentDOM.replaceChild(holder, scrollDOM);
-    holder.appendChild(scrollDOM);
-
-    const spacer = ownerDocument.createElement('div');
-    spacer.className = SPACER_CLASS;
-    scrollDOM.insertBefore(spacer, scrollDOM.firstChild);
-
-    let gutterWidth = 0;
-
-    scrollDOM.addEventListener('click', (event) => {
-      const scrollX = scrollDOM.scrollLeft + event.offsetX;
-      const scrollY = scrollDOM.scrollTop + event.offsetY;
-      if (scrollX > gutterWidth && scrollY > view.contentHeight) {
-        event.preventDefault();
-        view.focus();
-        editorStore.dispatch({
-          scrollIntoView: true,
-          selection: EditorSelection.create([
-            EditorSelection.cursor(view.state.doc.length),
-          ]),
-        });
-      }
-    });
-
-    let factorY = 1;
-    let factorX = 1;
-
-    const { track: trackY, thumb: thumbY } = createScrollbar(
-      holder,
-      'y',
-      (_offsetX, offsetY) => {
-        const scaledOffset = offsetY / factorY;
-        const { height: scrollerHeight } = scrollDOM.getBoundingClientRect();
-        const target = Math.max(0, scaledOffset - scrollerHeight / 2);
-        scrollDOM.scrollTo({ top: target });
-      },
-      (_movementX, movementY) => {
-        scrollDOM.scrollBy({ top: movementY / factorY });
-      },
-    );
-
-    const { track: trackX, thumb: thumbX } = createScrollbar(
-      holder,
-      'x',
-      (offsetX) => {
-        const scaledOffset = offsetX / factorX;
-        const { width: scrollerWidth } = scrollDOM.getBoundingClientRect();
-        const target = Math.max(0, scaledOffset - scrollerWidth / 2);
-        scrollDOM.scrollTo({ left: target });
-      },
-      (movementX) => {
-        scrollDOM.scrollBy({ left: movementX / factorX });
-      },
-    );
-
-    const gutterDecoration = ownerDocument.createElement('div');
-    gutterDecoration.className = GUTTER_DECORATION_CLASS;
-    holder.appendChild(gutterDecoration);
-
-    const topDecoration = ownerDocument.createElement('div');
-    topDecoration.className = TOP_DECORATION_CLASS;
-    holder.appendChild(topDecoration);
-
-    const disposePanelReaction = reaction(
-      () => editorStore.searchPanel.state,
-      (panelOpen) => {
-        topDecoration.style.display = panelOpen ? 'none' : 'block';
-      },
-      { fireImmediately: true },
-    );
-
-    let gutters: Element | undefined;
-
-    let firstRun = true;
-    let firstRunTimeout: number | undefined;
-    let requested = false;
-    let rebuildRequested = false;
-
-    const annotations: HTMLDivElement[] = [];
-
-    let observer: ResizeObserver | undefined;
-
-    function update() {
-      requested = false;
-
-      if (gutters === undefined) {
-        gutters = scrollDOM.querySelector('.cm-gutters') ?? undefined;
-        if (gutters !== undefined && observer !== undefined) {
-          observer.observe(gutters);
-        }
-      }
-
-      const { height: scrollerHeight, width: scrollerWidth } =
-        scrollDOM.getBoundingClientRect();
-      const { scrollTop, scrollLeft, scrollWidth } = scrollDOM;
-      const scrollHeight =
-        view.contentHeight + scrollerHeight - view.defaultLineHeight;
-      if (firstRun) {
-        if (firstRunTimeout !== undefined) {
-          clearTimeout(firstRunTimeout);
-        }
-        firstRunTimeout = setTimeout(() => {
-          spacer.style.minHeight = `${scrollHeight}px`;
-          firstRun = false;
-        }, 0);
-      } else {
-        spacer.style.minHeight = `${scrollHeight}px`;
-      }
-      gutterWidth = gutters?.clientWidth ?? 0;
-      let trackYHeight = scrollerHeight;
-
-      // Prevent spurious horizontal scrollbar by rounding up to the nearest pixel.
-      if (scrollWidth > Math.ceil(scrollerWidth)) {
-        // Leave space for horizontal scrollbar.
-        trackYHeight -= SCROLLBAR_WIDTH;
-        // Alwalys leave space for annotation in the vertical scrollbar.
-        const trackXWidth = scrollerWidth - gutterWidth - SCROLLBAR_WIDTH;
-        const thumbWidth = trackXWidth * (scrollerWidth / scrollWidth);
-        factorX = (trackXWidth - thumbWidth) / (scrollWidth - scrollerWidth);
-        trackY.style.bottom = `${SCROLLBAR_WIDTH}px`;
-        trackX.style.display = 'block';
-        trackX.style.left = `${gutterWidth}px`;
-        thumbX.style.width = `${thumbWidth}px`;
-        thumbX.style.left = `${scrollLeft * factorX}px`;
-        scrollDOM.style.overflowX = 'scroll';
-      } else {
-        trackY.style.bottom = '0px';
-        trackX.style.display = 'none';
-        scrollDOM.style.overflowX = 'hidden';
-      }
-
-      const thumbHeight = trackYHeight * (scrollerHeight / scrollHeight);
-      factorY = (trackYHeight - thumbHeight) / (scrollHeight - scrollerHeight);
-      thumbY.style.display = 'block';
-      thumbY.style.height = `${thumbHeight}px`;
-      thumbY.style.top = `${scrollTop * factorY}px`;
-
-      gutterDecoration.style.left = `${gutterWidth}px`;
-      gutterDecoration.style.width = `${Math.max(
-        0,
-        Math.min(scrollLeft, SHADOW_WIDTH),
-      )}px`;
-
-      topDecoration.style.height = `${Math.max(
-        0,
-        Math.min(scrollTop, SHADOW_WIDTH),
-      )}px`;
-
-      if (rebuildRequested) {
-        rebuildAnnotations(
-          view,
-          scrollHeight,
-          trackYHeight,
-          holder,
-          annotations,
-        );
-        rebuildRequested = false;
-      }
-    }
-
-    function requestUpdate() {
-      if (!requested) {
-        requested = true;
-        view.requestMeasure({ read: update });
-      }
-    }
-
-    function requestRebuild() {
-      requestUpdate();
-      rebuildRequested = true;
-    }
-
-    observer = new ResizeObserver(requestRebuild);
-    observer.observe(holder);
-
-    scrollDOM.addEventListener('scroll', requestUpdate);
-
-    requestRebuild();
-
-    return {
-      update: requestRebuild,
-      destroy() {
-        disposePanelReaction();
-        observer?.disconnect();
-        scrollDOM.removeEventListener('scroll', requestUpdate);
-        parentDOM.replaceChild(holder, holder);
-      },
-    };
-  });
-}
diff --git a/subprojects/frontend/src/editor/semanticHighlighting.ts b/subprojects/frontend/src/editor/semanticHighlighting.ts
index 2c1bd67d..1f2e564c 100644
--- a/subprojects/frontend/src/editor/semanticHighlighting.ts
+++ b/subprojects/frontend/src/editor/semanticHighlighting.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { RangeSet, type TransactionSpec } from '@codemirror/state';
 import { Decoration } from '@codemirror/view';
 
diff --git a/subprojects/frontend/src/index.tsx b/subprojects/frontend/src/index.tsx
index 29b2b196..cb11e6c3 100644
--- a/subprojects/frontend/src/index.tsx
+++ b/subprojects/frontend/src/index.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { configure } from 'mobx';
 import { type Root, createRoot } from 'react-dom/client';
 
diff --git a/subprojects/frontend/src/language/folding.ts b/subprojects/frontend/src/language/folding.ts
index 4dabfa27..b4d4ca22 100644
--- a/subprojects/frontend/src/language/folding.ts
+++ b/subprojects/frontend/src/language/folding.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type { EditorState } from '@codemirror/state';
 import type { SyntaxNode } from '@lezer/common';
 
diff --git a/subprojects/frontend/src/language/indentation.ts b/subprojects/frontend/src/language/indentation.ts
index a0f7032d..8446d7fa 100644
--- a/subprojects/frontend/src/language/indentation.ts
+++ b/subprojects/frontend/src/language/indentation.ts
@@ -1,3 +1,10 @@
+/*
+ * Copyright (C) 2018-2021 by Marijn Haverbeke <marijnh@gmail.com> and others
+ * Copyright (C) 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: MIT OR EPL-2.0
+ */
+
 import type { TreeIndentContext } from '@codemirror/language';
 
 /**
diff --git a/subprojects/frontend/src/language/problem.grammar b/subprojects/frontend/src/language/problem.grammar
index 704badab..a7b1fb0a 100644
--- a/subprojects/frontend/src/language/problem.grammar
+++ b/subprojects/frontend/src/language/problem.grammar
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 @detectDelim
 
 @external prop implicitCompletion from './props'
diff --git a/subprojects/frontend/src/language/problemLanguageSupport.ts b/subprojects/frontend/src/language/problemLanguageSupport.ts
index c3ae7ed9..2121e05f 100644
--- a/subprojects/frontend/src/language/problemLanguageSupport.ts
+++ b/subprojects/frontend/src/language/problemLanguageSupport.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import {
   foldInside,
   foldNodeProp,
diff --git a/subprojects/frontend/src/language/props.ts b/subprojects/frontend/src/language/props.ts
index 65392e75..aa67145a 100644
--- a/subprojects/frontend/src/language/props.ts
+++ b/subprojects/frontend/src/language/props.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 /* eslint-disable import/prefer-default-export -- Lezer needs non-default exports */
 
 import { NodeProp } from '@lezer/common';
diff --git a/subprojects/frontend/src/theme/ThemeProvider.tsx b/subprojects/frontend/src/theme/ThemeProvider.tsx
index ff97d524..78146f25 100644
--- a/subprojects/frontend/src/theme/ThemeProvider.tsx
+++ b/subprojects/frontend/src/theme/ThemeProvider.tsx
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import {
   alpha,
   createTheme,
@@ -69,7 +75,7 @@ function createResponsiveTheme(
     ...options,
     typography: {
       fontFamily:
-        '"InterVariable", "Inter", "Roboto", "Helvetica", "Arial", sans-serif',
+        '"Inter Variable", "Inter", "Roboto", "Helvetica", "Arial", sans-serif',
       fontWeightMedium: 600,
       fontWeightEditorNormal: 400,
       fontWeightEditorBold: 700,
@@ -79,7 +85,7 @@ function createResponsiveTheme(
       },
       editor: {
         fontFamily:
-          '"JetBrains MonoVariable", "JetBrains Mono", "Cascadia Code", "Fira Code", monospace',
+          '"JetBrains Mono Variable", "JetBrains Mono", "Cascadia Code", "Fira Code", monospace',
         fontFeatureSettings: '"liga", "calt"',
         // `rem` for JetBrains MonoVariable make the text too large in Safari.
         fontSize: '16px',
diff --git a/subprojects/frontend/src/theme/ThemeStore.ts b/subprojects/frontend/src/theme/ThemeStore.ts
index e09d8d99..7c657449 100644
--- a/subprojects/frontend/src/theme/ThemeStore.ts
+++ b/subprojects/frontend/src/theme/ThemeStore.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { makeAutoObservable } from 'mobx';
 
 export enum ThemePreference {
diff --git a/subprojects/frontend/src/utils/CancelledError.ts b/subprojects/frontend/src/utils/CancelledError.ts
index ee23676f..96b67af7 100644
--- a/subprojects/frontend/src/utils/CancelledError.ts
+++ b/subprojects/frontend/src/utils/CancelledError.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 export default class CancelledError extends Error {
   constructor(message = 'Operation cancelled') {
     super(message);
diff --git a/subprojects/frontend/src/utils/PendingTask.ts b/subprojects/frontend/src/utils/PendingTask.ts
index d0b24c1f..80d1a346 100644
--- a/subprojects/frontend/src/utils/PendingTask.ts
+++ b/subprojects/frontend/src/utils/PendingTask.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import TimeoutError from './TimeoutError';
 import getLogger from './getLogger';
 
diff --git a/subprojects/frontend/src/utils/PriorityMutex.ts b/subprojects/frontend/src/utils/PriorityMutex.ts
index 78736141..c1215c76 100644
--- a/subprojects/frontend/src/utils/PriorityMutex.ts
+++ b/subprojects/frontend/src/utils/PriorityMutex.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import CancelledError from './CancelledError';
 import PendingTask from './PendingTask';
 import getLogger from './getLogger';
diff --git a/subprojects/frontend/src/utils/TimeoutError.ts b/subprojects/frontend/src/utils/TimeoutError.ts
index eb800f40..21365502 100644
--- a/subprojects/frontend/src/utils/TimeoutError.ts
+++ b/subprojects/frontend/src/utils/TimeoutError.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 export default class TimeoutError extends Error {
   constructor() {
     super('Operation timed out');
diff --git a/subprojects/frontend/src/utils/getLogger.ts b/subprojects/frontend/src/utils/getLogger.ts
index 301fd76d..09b0b17f 100644
--- a/subprojects/frontend/src/utils/getLogger.ts
+++ b/subprojects/frontend/src/utils/getLogger.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import styles, { type CSPair } from 'ansi-styles';
 import log from 'loglevel';
 import prefix from 'loglevel-plugin-prefix';
diff --git a/subprojects/frontend/src/utils/useDelayedSnackbar.ts b/subprojects/frontend/src/utils/useDelayedSnackbar.ts
index 03ad6caa..3d6df3e3 100644
--- a/subprojects/frontend/src/utils/useDelayedSnackbar.ts
+++ b/subprojects/frontend/src/utils/useDelayedSnackbar.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import {
   useSnackbar,
   type SnackbarKey,
diff --git a/subprojects/frontend/src/xtext/BackendConfig.ts b/subprojects/frontend/src/xtext/BackendConfig.ts
index 41737c0b..4c7eac5f 100644
--- a/subprojects/frontend/src/xtext/BackendConfig.ts
+++ b/subprojects/frontend/src/xtext/BackendConfig.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 /* eslint-disable @typescript-eslint/no-redeclare -- Declare types with their companion objects */
 
 import { z } from 'zod';
diff --git a/subprojects/frontend/src/xtext/ContentAssistService.ts b/subprojects/frontend/src/xtext/ContentAssistService.ts
index 78f61c06..fd30c4f9 100644
--- a/subprojects/frontend/src/xtext/ContentAssistService.ts
+++ b/subprojects/frontend/src/xtext/ContentAssistService.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type {
   Completion,
   CompletionContext,
diff --git a/subprojects/frontend/src/xtext/HighlightingService.ts b/subprojects/frontend/src/xtext/HighlightingService.ts
index a126ee40..447f1401 100644
--- a/subprojects/frontend/src/xtext/HighlightingService.ts
+++ b/subprojects/frontend/src/xtext/HighlightingService.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type EditorStore from '../editor/EditorStore';
 import type { IHighlightRange } from '../editor/semanticHighlighting';
 
diff --git a/subprojects/frontend/src/xtext/OccurrencesService.ts b/subprojects/frontend/src/xtext/OccurrencesService.ts
index fc72ead2..c9c6c699 100644
--- a/subprojects/frontend/src/xtext/OccurrencesService.ts
+++ b/subprojects/frontend/src/xtext/OccurrencesService.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type { Transaction } from '@codemirror/state';
 import { debounce } from 'lodash-es';
 import ms from 'ms';
diff --git a/subprojects/frontend/src/xtext/UpdateService.ts b/subprojects/frontend/src/xtext/UpdateService.ts
index 63e28652..ee5ebde2 100644
--- a/subprojects/frontend/src/xtext/UpdateService.ts
+++ b/subprojects/frontend/src/xtext/UpdateService.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type { ChangeDesc, Transaction } from '@codemirror/state';
 import { debounce } from 'lodash-es';
 import { nanoid } from 'nanoid';
diff --git a/subprojects/frontend/src/xtext/UpdateStateTracker.ts b/subprojects/frontend/src/xtext/UpdateStateTracker.ts
index 5d4ce49e..4ce93ed6 100644
--- a/subprojects/frontend/src/xtext/UpdateStateTracker.ts
+++ b/subprojects/frontend/src/xtext/UpdateStateTracker.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import {
   type ChangeDesc,
   ChangeSet,
diff --git a/subprojects/frontend/src/xtext/ValidationService.ts b/subprojects/frontend/src/xtext/ValidationService.ts
index 72414590..64fb63eb 100644
--- a/subprojects/frontend/src/xtext/ValidationService.ts
+++ b/subprojects/frontend/src/xtext/ValidationService.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type { Diagnostic } from '@codemirror/lint';
 
 import type EditorStore from '../editor/EditorStore';
diff --git a/subprojects/frontend/src/xtext/XtextClient.ts b/subprojects/frontend/src/xtext/XtextClient.ts
index 14fb2430..e8181af0 100644
--- a/subprojects/frontend/src/xtext/XtextClient.ts
+++ b/subprojects/frontend/src/xtext/XtextClient.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import type {
   CompletionContext,
   CompletionResult,
diff --git a/subprojects/frontend/src/xtext/XtextWebSocketClient.ts b/subprojects/frontend/src/xtext/XtextWebSocketClient.ts
index 6b734546..6bb7eec8 100644
--- a/subprojects/frontend/src/xtext/XtextWebSocketClient.ts
+++ b/subprojects/frontend/src/xtext/XtextWebSocketClient.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import { createAtom, makeAutoObservable, observable } from 'mobx';
 import ms from 'ms';
 import { nanoid } from 'nanoid';
diff --git a/subprojects/frontend/src/xtext/fetchBackendConfig.ts b/subprojects/frontend/src/xtext/fetchBackendConfig.ts
index 15e976d8..71ff2e63 100644
--- a/subprojects/frontend/src/xtext/fetchBackendConfig.ts
+++ b/subprojects/frontend/src/xtext/fetchBackendConfig.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import BackendConfig, { ENDPOINT } from './BackendConfig';
 
 export default async function fetchBackendConfig(): Promise<BackendConfig> {
diff --git a/subprojects/frontend/src/xtext/webSocketMachine.ts b/subprojects/frontend/src/xtext/webSocketMachine.ts
index fc53fef3..2fb1f52f 100644
--- a/subprojects/frontend/src/xtext/webSocketMachine.ts
+++ b/subprojects/frontend/src/xtext/webSocketMachine.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import ms from 'ms';
 import { actions, assign, createMachine } from 'xstate';
 
diff --git a/subprojects/frontend/src/xtext/xtextMessages.ts b/subprojects/frontend/src/xtext/xtextMessages.ts
index ec7a2a31..bbbff064 100644
--- a/subprojects/frontend/src/xtext/xtextMessages.ts
+++ b/subprojects/frontend/src/xtext/xtextMessages.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 /* eslint-disable @typescript-eslint/no-redeclare -- Declare types with their companion objects */
 
 import { z } from 'zod';
diff --git a/subprojects/frontend/src/xtext/xtextServiceResults.ts b/subprojects/frontend/src/xtext/xtextServiceResults.ts
index e93c6714..d3b467ad 100644
--- a/subprojects/frontend/src/xtext/xtextServiceResults.ts
+++ b/subprojects/frontend/src/xtext/xtextServiceResults.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 /* eslint-disable @typescript-eslint/no-redeclare -- Declare types with their companion objects */
 
 import { z } from 'zod';
diff --git a/subprojects/frontend/tsconfig.base.json b/subprojects/frontend/tsconfig.base.json
index b960e93c..5ef50b5e 100644
--- a/subprojects/frontend/tsconfig.base.json
+++ b/subprojects/frontend/tsconfig.base.json
@@ -1,10 +1,41 @@
+/*
+ * Copyright (c) Microsoft Corporation.
+ * Copyright (c) 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: MIT OR EPL-2.0
+ *
+ * This file is based on
+ * https://github.com/tsconfig/bases/blob/7db25a41bc5a9c0f66d91f6f3aa28438afcb2f18/bases/strictest.json
+ * but we moved it inside the project for better tooling support.
+ */
 {
-  "extends": "@tsconfig/strictest",
   "compilerOptions": {
-    "useDefineForClassFields": true,
-    "verbatimModuleSyntax": false,
+    "strict": true,
+    "allowUnusedLabels": false,
+    "allowUnreachableCode": false,
+    "exactOptionalPropertyTypes": true,
+    "noFallthroughCasesInSwitch": true,
+    "noImplicitOverride": true,
+    "noImplicitReturns": true,
+    "noPropertyAccessFromIndexSignature": true,
+    "noUncheckedIndexedAccess": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    // "verbatimModuleSyntax" is incompatible with `import` syntax in modules
+    // with CommonJS import resolution, so we use "isolatedModules" only.
+    // "verbatimModuleSyntax": false,
     "isolatedModules": true,
+    "checkJs": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+    "useDefineForClassFields": true,
+    // Project-specific configuration below.
     "module": "es2022",
-    "moduleResolution": "node"
+    "moduleResolution": "node",
+    "incremental": true,
+    "declaration": true,
+    "emitDeclarationOnly": true,
+    "outDir": "build/typescript"
   }
 }
diff --git a/subprojects/frontend/tsconfig.json b/subprojects/frontend/tsconfig.json
index 35abd789..06f6d8fe 100644
--- a/subprojects/frontend/tsconfig.json
+++ b/subprojects/frontend/tsconfig.json
@@ -1,8 +1,12 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 {
   "extends": "./tsconfig.base.json",
   "compilerOptions": {
     "jsx": "react-jsx",
-    "noEmit": true,
     "lib": ["DOM", "DOM.Iterable", "ES2022"],
     "types": ["vite/client", "vite-plugin-pwa/client"]
   },
diff --git a/subprojects/frontend/tsconfig.node.json b/subprojects/frontend/tsconfig.node.json
index f4908bcb..47feaf97 100644
--- a/subprojects/frontend/tsconfig.node.json
+++ b/subprojects/frontend/tsconfig.node.json
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 {
   "extends": "./tsconfig.base.json",
   "compilerOptions": {
@@ -10,6 +15,7 @@
   "include": [
     ".eslintrc.cjs",
     "config/*.ts",
+    "config/*.cjs",
     "prettier.config.cjs",
     "types/node",
     "vite.config.ts"
diff --git a/subprojects/frontend/tsconfig.shared.json b/subprojects/frontend/tsconfig.shared.json
index b7e1de55..154fe122 100644
--- a/subprojects/frontend/tsconfig.shared.json
+++ b/subprojects/frontend/tsconfig.shared.json
@@ -1,13 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 {
   "extends": "./tsconfig.base.json",
   "compilerOptions": {
     "composite": true,
     "lib": ["ES2022"],
     "types": [],
-    "emitDeclarationOnly": true,
-    "outDir": "build/typescript"
   },
   "include": [
-    "src/xtext/BackendConfig.ts",
+    "src/xtext/BackendConfig.ts"
   ]
 }
diff --git a/subprojects/frontend/types/ImportMeta.d.ts b/subprojects/frontend/types/ImportMeta.d.ts
index c32b48f5..f5a32ef1 100644
--- a/subprojects/frontend/types/ImportMeta.d.ts
+++ b/subprojects/frontend/types/ImportMeta.d.ts
@@ -1,3 +1,10 @@
+/*
+ * Copyright (c) 2019-present, Yuxi (Evan) You and Vite contributors
+ * Copyright (c) 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: MIT OR EPL-2.0
+ */
+
 interface ImportMeta {
   env: {
     BASE_URL: string;
diff --git a/subprojects/frontend/types/grammar.d.ts b/subprojects/frontend/types/grammar.d.ts
index 1480085b..e7a7eebf 100644
--- a/subprojects/frontend/types/grammar.d.ts
+++ b/subprojects/frontend/types/grammar.d.ts
@@ -1,3 +1,10 @@
+/*
+ * Copyright (C) 2018 by Marijn Haverbeke <marijn@haverbeke.berlin> and others
+ * Copyright (C) 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: MIT OR EPL-2.0
+ */
+
 declare module '*.grammar' {
   import type { LRParser } from '@lezer/lr';
 
diff --git a/subprojects/frontend/types/node/@lezer-generator-rollup.d.ts b/subprojects/frontend/types/node/@lezer-generator-rollup.d.ts
index 9c1ff03e..4ef9f4e3 100644
--- a/subprojects/frontend/types/node/@lezer-generator-rollup.d.ts
+++ b/subprojects/frontend/types/node/@lezer-generator-rollup.d.ts
@@ -1,3 +1,10 @@
+/*
+ * Copyright (C) 2018 by Marijn Haverbeke <marijn@haverbeke.berlin> and others
+ * Copyright (C) 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: MIT OR EPL-2.0
+ */
+
 // We have to explicitly redeclare the type of the `./rollup` ESM export of `@lezer/generator`,
 // because TypeScript can't find it on its own even with `"moduleResolution": "Node16"`.
 declare module '@lezer/generator/rollup' {
diff --git a/subprojects/frontend/types/windowControlsOverlay.d.ts b/subprojects/frontend/types/windowControlsOverlay.d.ts
index d8f3182f..2513d620 100644
--- a/subprojects/frontend/types/windowControlsOverlay.d.ts
+++ b/subprojects/frontend/types/windowControlsOverlay.d.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 interface WindowControlsOverlayGeometryChangeEvent extends Event {
   titlebarAreaRect: DOMRect;
 
diff --git a/subprojects/frontend/vite.config.ts b/subprojects/frontend/vite.config.ts
index cd9993cc..9e08ccc4 100644
--- a/subprojects/frontend/vite.config.ts
+++ b/subprojects/frontend/vite.config.ts
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
 
diff --git a/subprojects/language-ide/build.gradle b/subprojects/language-ide/build.gradle
deleted file mode 100644
index 3786762b..00000000
--- a/subprojects/language-ide/build.gradle
+++ /dev/null
@@ -1,18 +0,0 @@
-plugins {
-        id 'refinery-java-library'
-        id 'refinery-xtext-conventions'
-}
-
-dependencies {
-        api project(':refinery-language')
-        api libs.xtext.ide
-        api libs.xtext.xbase.ide
-}
-
-def generateXtextLanguage = project(':refinery-language').tasks.named('generateXtextLanguage')
-
-for (taskName in ['compileJava', 'processResources']) {
-        tasks.named(taskName) {
-                dependsOn generateXtextLanguage
-        }
-}
diff --git a/subprojects/language-ide/build.gradle.kts b/subprojects/language-ide/build.gradle.kts
new file mode 100644
index 00000000..1259cd67
--- /dev/null
+++ b/subprojects/language-ide/build.gradle.kts
@@ -0,0 +1,18 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+plugins {
+        id("tools.refinery.gradle.java-library")
+        id("tools.refinery.gradle.xtext-generated")
+}
+
+dependencies {
+        api(project(":refinery-language"))
+        api(libs.xtext.ide)
+        api(libs.xtext.xbase.ide)
+        xtextGenerated(project(":refinery-language", "generatedIdeSources"))
+}
+
diff --git a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/ProblemIdeModule.java b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/ProblemIdeModule.java
index fb620065..122fe874 100644
--- a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/ProblemIdeModule.java
+++ b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/ProblemIdeModule.java
@@ -1,4 +1,10 @@
 /*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+/*
  * generated by Xtext 2.25.0
  */
 package tools.refinery.language.ide;
diff --git a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/ProblemIdeSetup.java b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/ProblemIdeSetup.java
index 5b88d41f..9d77e022 100644
--- a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/ProblemIdeSetup.java
+++ b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/ProblemIdeSetup.java
@@ -1,4 +1,10 @@
 /*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+/*
  * generated by Xtext 2.25.0
  */
 package tools.refinery.language.ide;
diff --git a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/FuzzyMatcher.java b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/FuzzyMatcher.java
index fe722ca1..4511223b 100644
--- a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/FuzzyMatcher.java
+++ b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/FuzzyMatcher.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.ide.contentassist;
 
 import org.eclipse.xtext.ide.editor.contentassist.IPrefixMatcher;
diff --git a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/ProblemCrossrefProposalProvider.java b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/ProblemCrossrefProposalProvider.java
index 8f04ed00..e194ee31 100644
--- a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/ProblemCrossrefProposalProvider.java
+++ b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/ProblemCrossrefProposalProvider.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.ide.contentassist;
 
 import java.util.Objects;
diff --git a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/TokenSourceInjectingPartialProblemContentAssistParser.java b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/TokenSourceInjectingPartialProblemContentAssistParser.java
index 3ece6f67..146bd8da 100644
--- a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/TokenSourceInjectingPartialProblemContentAssistParser.java
+++ b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/TokenSourceInjectingPartialProblemContentAssistParser.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.ide.contentassist;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/TokenSourceInjectingProblemParser.java b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/TokenSourceInjectingProblemParser.java
index 80dfee5c..f906d881 100644
--- a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/TokenSourceInjectingProblemParser.java
+++ b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/TokenSourceInjectingProblemParser.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.ide.contentassist;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/antlr/ProblemTokenSource.java b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/antlr/ProblemTokenSource.java
index c6c7f41f..fdc17c4f 100644
--- a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/antlr/ProblemTokenSource.java
+++ b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/antlr/ProblemTokenSource.java
@@ -1,4 +1,10 @@
 /*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+/*
  * generated by Xtext 2.29.0.M2
  */
 package tools.refinery.language.ide.contentassist.antlr;
diff --git a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java
index 7703e4e3..e8f97d51 100644
--- a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java
+++ b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.ide.syntaxcoloring;
 
 import com.google.common.collect.ImmutableList;
diff --git a/subprojects/language-model/META-INF/MANIFEST.MF.license b/subprojects/language-model/META-INF/MANIFEST.MF.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/language-model/META-INF/MANIFEST.MF.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/language-model/build.gradle b/subprojects/language-model/build.gradle
deleted file mode 100644
index 275db188..00000000
--- a/subprojects/language-model/build.gradle
+++ /dev/null
@@ -1,55 +0,0 @@
-plugins {
-        id 'refinery-java-library'
-        id 'refinery-mwe2'
-        id 'refinery-sonarqube'
-}
-
-dependencies {
-        api libs.ecore
-        api libs.ecore.xmi
-        mwe2 libs.ecore.codegen
-        mwe2 libs.mwe.utils
-        mwe2 libs.mwe2.lib
-        mwe2 libs.xtext.core
-        mwe2 libs.xtext.xbase
-}
-
-sourceSets {
-        main {
-                java.srcDirs += ['src/main/emf-gen']
-        }
-}
-
-def generateEPackage = tasks.register('generateEPackage', JavaExec) {
-        mainClass = 'org.eclipse.emf.mwe2.launch.runtime.Mwe2Launcher'
-        classpath = configurations.mwe2
-        inputs.file 'src/main/java/tools/refinery/language/model/GenerateProblemModel.mwe2'
-        inputs.file 'src/main/resources/model/problem.ecore'
-        inputs.file 'src/main/resources/model/problem.genmodel'
-        outputs.dir 'src/main/emf-gen'
-        args += 'src/main/java/tools/refinery/language/model/GenerateProblemModel.mwe2'
-        args += '-p'
-        args += "rootPath=/${projectDir}"
-}
-
-for (taskName in ['compileJava', 'processResources', 'generateEclipseSourceFolders']) {
-        tasks.named(taskName) {
-                dependsOn generateEPackage
-        }
-}
-
-tasks.named('clean') {
-        delete 'src/main/emf-gen'
-}
-
-sonarqube.properties {
-        properties['sonar.exclusions'] += [
-                'src/main/emf-gen/**',
-        ]
-}
-
-eclipse.project.natures += [
-        'org.eclipse.sirius.nature.modelingproject',
-        'org.eclipse.pde.PluginNature',
-        'org.eclipse.xtext.ui.shared.xtextNature'
-]
diff --git a/subprojects/language-model/build.gradle.kts b/subprojects/language-model/build.gradle.kts
new file mode 100644
index 00000000..59ff9046
--- /dev/null
+++ b/subprojects/language-model/build.gradle.kts
@@ -0,0 +1,65 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+import tools.refinery.gradle.utils.SonarPropertiesUtils
+
+plugins {
+        id("tools.refinery.gradle.java-library")
+        id("tools.refinery.gradle.mwe2")
+        id("tools.refinery.gradle.sonarqube")
+}
+
+dependencies {
+        api(libs.ecore)
+        api(libs.ecore.xmi)
+        mwe2(libs.ecore.codegen)
+        mwe2(libs.mwe.utils)
+        mwe2(libs.mwe2.lib)
+        mwe2(libs.xtext.core)
+        mwe2(libs.xtext.xbase)
+}
+
+sourceSets {
+        main {
+                java.srcDir("src/main/emf-gen")
+        }
+}
+
+tasks {
+        val generateEPackage by registering(JavaExec::class) {
+                mainClass.set("org.eclipse.emf.mwe2.launch.runtime.Mwe2Launcher")
+                classpath(configurations.mwe2)
+                inputs.file("src/main/java/tools/refinery/language/model/GenerateProblemModel.mwe2")
+                inputs.file("src/main/resources/model/problem.ecore")
+                inputs.file("src/main/resources/model/problem.genmodel")
+                outputs.file("build.properties")
+                outputs.file("META-INF/MANIFEST.MF")
+                outputs.file("plugin.xml")
+                outputs.file("plugin.properties")
+                outputs.dir("src/main/emf-gen")
+                args("src/main/java/tools/refinery/language/model/GenerateProblemModel.mwe2", "-p", "rootPath=/$projectDir")
+        }
+
+        for (taskName in listOf("compileJava", "processResources", "generateEclipseSourceFolders")) {
+                named(taskName) {
+                        dependsOn(generateEPackage)
+                }
+        }
+
+        clean {
+                delete("src/main/emf-gen")
+        }
+}
+
+sonarqube.properties {
+        SonarPropertiesUtils.addToList(properties, "sonar.exclusions", "src/main/emf-gen/**")
+}
+
+eclipse.project.natures.plusAssign(listOf(
+                "org.eclipse.sirius.nature.modelingproject",
+                "org.eclipse.pde.PluginNature",
+                "org.eclipse.xtext.ui.shared.xtextNature",
+))
diff --git a/subprojects/language-model/build.properties b/subprojects/language-model/build.properties
index 65dfc7c4..9b9859ff 100644
--- a/subprojects/language-model/build.properties
+++ b/subprojects/language-model/build.properties
@@ -1,4 +1,6 @@
+# SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
 #
+# SPDX-License-Identifier: EPL-2.0
 
 bin.includes = .,\
                src/main/resources/model/,\
diff --git a/subprojects/language-model/plugin.properties b/subprojects/language-model/plugin.properties
index c4fb7e23..c410feb7 100644
--- a/subprojects/language-model/plugin.properties
+++ b/subprojects/language-model/plugin.properties
@@ -1,4 +1,6 @@
+# SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
 #
+# SPDX-License-Identifier: EPL-2.0
 
 pluginName = tools.refinery.language.model
 providerName = refinery.tools
diff --git a/subprojects/language-model/plugin.xml b/subprojects/language-model/plugin.xml
index 4ca005a8..ef1e21f4 100644
--- a/subprojects/language-model/plugin.xml
+++ b/subprojects/language-model/plugin.xml
@@ -2,6 +2,9 @@
 <?eclipse version="3.0"?>
 
 <!--
+  SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+  SPDX-License-Identifier: EPL-2.0
 -->
 
 <plugin>
diff --git a/subprojects/language-model/problem.aird.license b/subprojects/language-model/problem.aird.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/language-model/problem.aird.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/language-model/src/main/java/tools/refinery/language/model/GenerateProblemModel.mwe2 b/subprojects/language-model/src/main/java/tools/refinery/language/model/GenerateProblemModel.mwe2
index 15198d69..074b6b71 100644
--- a/subprojects/language-model/src/main/java/tools/refinery/language/model/GenerateProblemModel.mwe2
+++ b/subprojects/language-model/src/main/java/tools/refinery/language/model/GenerateProblemModel.mwe2
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 module tools.refinery.language.model.GenerateProblemModel
 
 Workflow {
diff --git a/subprojects/language-model/src/main/resources/model/problem.ecore.license b/subprojects/language-model/src/main/resources/model/problem.ecore.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/language-model/src/main/resources/model/problem.ecore.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/language-model/src/main/resources/model/problem.genmodel.license b/subprojects/language-model/src/main/resources/model/problem.genmodel.license
new file mode 100644
index 00000000..e5db6ccd
--- /dev/null
+++ b/subprojects/language-model/src/main/resources/model/problem.genmodel.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+SPDX-License-Identifier: EPL-2.0
diff --git a/subprojects/language-semantics/build.gradle b/subprojects/language-semantics/build.gradle
deleted file mode 100644
index 4f43ad24..00000000
--- a/subprojects/language-semantics/build.gradle
+++ /dev/null
@@ -1,11 +0,0 @@
-plugins {
-        id 'refinery-java-library'
-}
-
-dependencies {
-        implementation libs.eclipseCollections
-        implementation libs.eclipseCollections.api
-        api project(':refinery-language')
-        api project(':refinery-store')
-        testImplementation testFixtures(project(':refinery-language'))
-}
diff --git a/subprojects/language-semantics/build.gradle.kts b/subprojects/language-semantics/build.gradle.kts
new file mode 100644
index 00000000..38cd9e0d
--- /dev/null
+++ b/subprojects/language-semantics/build.gradle.kts
@@ -0,0 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+plugins {
+        id("tools.refinery.gradle.java-library")
+}
+
+dependencies {
+        implementation(libs.eclipseCollections)
+        implementation(libs.eclipseCollections.api)
+        api(project(":refinery-language"))
+        api(project(":refinery-store"))
+        testImplementation(testFixtures(project(":refinery-language")))
+}
diff --git a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/ModelInitializer.java b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/ModelInitializer.java
index a6712a89..06b8ad77 100644
--- a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/ModelInitializer.java
+++ b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/ModelInitializer.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.semantics.model;
 
 import com.google.inject.Inject;
@@ -39,8 +44,8 @@ public class ModelInitializer {
                         var isEqualsRelation = relation == builtinSymbols.equals();
                         var decisionTree = mergeAssertions(relationInfo, isEqualsRelation);
                         var defaultValue = isEqualsRelation ? TruthValue.FALSE : TruthValue.UNKNOWN;
-                        relationTrace.put(relation, new Symbol<>(relationInfo.name(), relationInfo.arity(), TruthValue.class, defaultValue
-                        ));
+                        relationTrace.put(relation, Symbol.of(
+                                        relationInfo.name(), relationInfo.arity(), TruthValue.class, defaultValue));
                 }
         }
 
diff --git a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTree.java b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTree.java
index 55edee6d..c1afecf9 100644
--- a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTree.java
+++ b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTree.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.semantics.model.internal;
 
 import org.eclipse.collections.api.factory.primitive.IntObjectMaps;
diff --git a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTreeCursor.java b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTreeCursor.java
index fdf8e452..9a1e15a3 100644
--- a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTreeCursor.java
+++ b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTreeCursor.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.semantics.model.internal;
 
 import tools.refinery.store.map.Cursor;
diff --git a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTreeNode.java b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTreeNode.java
index b81ea3fe..3c54e3c5 100644
--- a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTreeNode.java
+++ b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTreeNode.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.semantics.model.internal;
 
 import org.eclipse.collections.api.LazyIntIterable;
diff --git a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTreeValue.java b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTreeValue.java
index 495a53dd..915ae2bf 100644
--- a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTreeValue.java
+++ b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/DecisionTreeValue.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.semantics.model.internal;
 
 import tools.refinery.store.representation.TruthValue;
diff --git a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/IntermediateNode.java b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/IntermediateNode.java
index c4200509..e6f01d48 100644
--- a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/IntermediateNode.java
+++ b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/IntermediateNode.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.semantics.model.internal;
 
 import org.eclipse.collections.api.LazyIntIterable;
diff --git a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/TerminalNode.java b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/TerminalNode.java
index 4af836ff..ce49aa62 100644
--- a/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/TerminalNode.java
+++ b/subprojects/language-semantics/src/main/java/tools/refinery/language/semantics/model/internal/TerminalNode.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.semantics.model.internal;
 
 import org.eclipse.collections.api.LazyIntIterable;
diff --git a/subprojects/language-semantics/src/test/java/tools/refinery/language/semantics/model/tests/DecisionTreeTests.java b/subprojects/language-semantics/src/test/java/tools/refinery/language/semantics/model/tests/DecisionTreeTests.java
index 4630bf53..b3fcbabb 100644
--- a/subprojects/language-semantics/src/test/java/tools/refinery/language/semantics/model/tests/DecisionTreeTests.java
+++ b/subprojects/language-semantics/src/test/java/tools/refinery/language/semantics/model/tests/DecisionTreeTests.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.semantics.model.tests;
 
 import org.junit.jupiter.api.Test;
diff --git a/subprojects/language-web/build.gradle b/subprojects/language-web/build.gradle
deleted file mode 100644
index 8d277a5b..00000000
--- a/subprojects/language-web/build.gradle
+++ /dev/null
@@ -1,87 +0,0 @@
-plugins {
-        id 'refinery-java-application'
-        id 'refinery-xtext-conventions'
-}
-
-configurations {
-        webapp {
-                canBeConsumed = false
-                canBeResolved = true
-        }
-
-        all {
-                // Use log4j-over-slf4j instead of log4j 1.x
-                exclude group: 'log4j', module: 'log4j'
-        }
-}
-
-dependencies {
-        implementation project(':refinery-language')
-        implementation project(':refinery-language-ide')
-        implementation libs.jetty.server
-        implementation libs.jetty.servlet
-        implementation libs.jetty.websocket.server
-        implementation libs.slf4j.api
-        implementation libs.slf4j.simple
-        implementation libs.slf4j.log4j
-        implementation libs.xtext.web
-        webapp project(path: ':refinery-frontend', configuration: 'productionAssets')
-        testImplementation testFixtures(project(':refinery-language'))
-        testImplementation libs.jetty.websocket.client
-}
-
-def generateXtextLanguage = project(':refinery-language').tasks.named('generateXtextLanguage')
-
-for (taskName in ['compileJava', 'processResources']) {
-        tasks.named(taskName) {
-                dependsOn generateXtextLanguage
-        }
-}
-
-mainClassName = 'tools.refinery.language.web.ServerLauncher'
-
-// Enable JDK 19 preview features for virtual thread support.
-application {
-        applicationDefaultJvmArgs += '--enable-preview'
-}
-tasks.withType(JavaCompile) {
-        options.release = 19
-        options.compilerArgs += '--enable-preview'
-}
-tasks.withType(Test) {
-        jvmArgs += '--enable-preview'
-}
-
-tasks.named('jar') {
-        dependsOn project.configurations.webapp
-        from(project.configurations.webapp) {
-                into 'webapp'
-        }
-}
-
-tasks.named('shadowJar') {
-        dependsOn project.configurations.webapp
-        from(project.sourceSets.main.output)
-        configurations = [project.configurations.runtimeClasspath]
-        exclude('META-INF/INDEX.LIST', 'META-INF/*.SF', 'META-INF/*.DSA', 'META-INF/*.RSA','schema/*',
-                '.options', '.api_description', '*.profile', 'about.*', 'about_*.html', 'about_files/*',
-                'plugin.xml', 'systembundle.properties', 'profile.list', 'META-INF/resources/xtext/**')
-        append('plugin.properties')
-        from(project.configurations.webapp) {
-                into 'webapp'
-        }
-}
-
-tasks.register('serveBackend', JavaExec) {
-        dependsOn project.configurations.webapp
-        dependsOn sourceSets.main.runtimeClasspath
-        classpath = sourceSets.main.runtimeClasspath
-        mainClass = mainClassName
-        // Enable JDK 19 preview features for virtual thread support.
-        jvmArgs += '--enable-preview'
-        standardInput = System.in
-        def baseResource = project.configurations.webapp.incoming.artifacts.artifactFiles.first()
-        environment BASE_RESOURCE: baseResource
-        group = 'run'
-        description = 'Start a Jetty web server serving the Xtex API and assets.'
-}
diff --git a/subprojects/language-web/build.gradle.kts b/subprojects/language-web/build.gradle.kts
new file mode 100644
index 00000000..562a1bd9
--- /dev/null
+++ b/subprojects/language-web/build.gradle.kts
@@ -0,0 +1,68 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+plugins {
+        id("tools.refinery.gradle.java-application")
+        id("tools.refinery.gradle.xtext-generated")
+}
+
+val webapp: Configuration by configurations.creating {
+        isCanBeConsumed = false
+        isCanBeResolved = true
+}
+
+dependencies {
+        implementation(project(":refinery-language"))
+        implementation(project(":refinery-language-ide"))
+        implementation(libs.jetty.server)
+        implementation(libs.jetty.servlet)
+        implementation(libs.jetty.websocket.api)
+        implementation(libs.jetty.websocket.server)
+        implementation(libs.slf4j.api)
+        implementation(libs.xtext.web)
+        xtextGenerated(project(":refinery-language", "generatedWebSources"))
+        webapp(project(":refinery-frontend", "productionAssets"))
+        testImplementation(testFixtures(project(":refinery-language")))
+        testImplementation(libs.jetty.websocket.client)
+}
+
+application {
+        mainClass.set("tools.refinery.language.web.ServerLauncher")
+}
+
+tasks {
+        jar {
+                dependsOn(webapp)
+                from(webapp) {
+                        into("webapp")
+                }
+        }
+
+        shadowJar {
+                dependsOn(webapp)
+                from(project.sourceSets.main.map { it.output })
+                exclude("META-INF/INDEX.LIST", "META-INF/*.SF", "META-INF/*.DSA", "META-INF/*.RSA", "schema/*",
+                                ".options", ".api_description", "*.profile", "about.*", "about_*.html", "about_files/*",
+                                "plugin.xml", "systembundle.properties", "profile.list", "META-INF/resources/xtext/**")
+                append("plugin.properties")
+                from(webapp) {
+                        into("webapp")
+                }
+        }
+
+        register<JavaExec>("serveBackend") {
+                dependsOn(webapp)
+                val mainRuntimeClasspath = sourceSets.main.map { it.runtimeClasspath }
+                dependsOn(mainRuntimeClasspath)
+                classpath(mainRuntimeClasspath)
+                mainClass.set(application.mainClass)
+                standardInput = System.`in`
+                val baseResource = webapp.incoming.artifacts.artifactFiles.first()
+                environment("BASE_RESOURCE", baseResource)
+                group = "run"
+                description = "Start a Jetty web server serving the Xtex API and assets."
+        }
+}
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/CacheControlFilter.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/CacheControlFilter.java
index fd2af1b2..53f78c3c 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/CacheControlFilter.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/CacheControlFilter.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web;
 
 import jakarta.servlet.*;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/ProblemWebModule.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/ProblemWebModule.java
index 706413a9..b0197c01 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/ProblemWebModule.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/ProblemWebModule.java
@@ -1,15 +1,19 @@
 /*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+/*
  * generated by Xtext 2.25.0
  */
 package tools.refinery.language.web;
 
-import org.eclipse.xtext.ide.ExecutorServiceProvider;
 import org.eclipse.xtext.web.server.XtextServiceDispatcher;
 import org.eclipse.xtext.web.server.model.IWebDocumentProvider;
 import org.eclipse.xtext.web.server.model.XtextWebDocumentAccess;
 import org.eclipse.xtext.web.server.occurrences.OccurrencesService;
 import tools.refinery.language.web.occurrences.ProblemOccurrencesService;
-import tools.refinery.language.web.xtext.VirtualThreadExecutorServiceProvider;
 import tools.refinery.language.web.xtext.server.push.PushServiceDispatcher;
 import tools.refinery.language.web.xtext.server.push.PushWebDocumentAccess;
 import tools.refinery.language.web.xtext.server.push.PushWebDocumentProvider;
@@ -33,8 +37,4 @@ public class ProblemWebModule extends AbstractProblemWebModule {
         public Class<? extends OccurrencesService> bindOccurrencesService() {
                 return ProblemOccurrencesService.class;
         }
-
-        public Class<? extends ExecutorServiceProvider> bindExecutorServiceProvider() {
-                return VirtualThreadExecutorServiceProvider.class;
-        }
 }
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/ProblemWebSetup.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/ProblemWebSetup.java
index 4738bc80..53a394d8 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/ProblemWebSetup.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/ProblemWebSetup.java
@@ -1,4 +1,10 @@
 /*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+/*
  * generated by Xtext 2.25.0
  */
 package tools.refinery.language.web;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/ProblemWebSocketServlet.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/ProblemWebSocketServlet.java
index df67b521..7b48cde8 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/ProblemWebSocketServlet.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/ProblemWebSocketServlet.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web;
 
 import org.eclipse.xtext.util.DisposableRegistry;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/SecurityHeadersFilter.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/SecurityHeadersFilter.java
index c41db799..7b094fde 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/SecurityHeadersFilter.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/SecurityHeadersFilter.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web;
 
 import jakarta.servlet.*;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/ServerLauncher.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/ServerLauncher.java
index f49f46ee..ad19e77d 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/ServerLauncher.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/ServerLauncher.java
@@ -1,4 +1,10 @@
 /*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+/*
  * generated by Xtext 2.25.0
  */
 package tools.refinery.language.web;
@@ -13,6 +19,7 @@ import org.eclipse.jetty.ee10.websocket.server.config.JettyWebSocketServletConta
 import org.eclipse.jetty.server.Server;
 import org.eclipse.jetty.util.resource.Resource;
 import org.eclipse.jetty.util.resource.ResourceFactory;
+import org.eclipse.jetty.util.thread.QueuedThreadPool;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import tools.refinery.language.web.config.BackendConfigServlet;
@@ -43,7 +50,8 @@ public class ServerLauncher {
         private final Server server;
 
         public ServerLauncher(InetSocketAddress bindAddress, String[] allowedOrigins, String webSocketUrl) {
-                server = VirtualThreadUtils.newServerWithVirtualThreadsThreadPool("jetty", bindAddress);
+                server = new Server(bindAddress);
+                ((QueuedThreadPool) server.getThreadPool()).setName("jetty");
                 var handler = new ServletContextHandler();
                 addSessionHandler(handler);
                 addProblemServlet(handler, allowedOrigins);
@@ -105,7 +113,7 @@ public class ServerLauncher {
                 var indexUrlInJar = ServerLauncher.class.getResource("/webapp/index.html");
                 if (indexUrlInJar != null) {
                         // If the app is packaged in the jar, serve it.
-                        URI webRootUri = null;
+                        URI webRootUri;
                         try {
                                 webRootUri = URI.create(indexUrlInJar.toURI().toASCIIString().replaceFirst("/index.html$", "/"));
                         } catch (URISyntaxException e) {
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/VirtualThreadUtils.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/VirtualThreadUtils.java
deleted file mode 100644
index a055e755..00000000
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/VirtualThreadUtils.java
+++ /dev/null
@@ -1,52 +0,0 @@
-package tools.refinery.language.web;
-
-import org.eclipse.jetty.server.Server;
-import org.eclipse.jetty.server.ServerConnector;
-import org.eclipse.jetty.util.thread.QueuedThreadPool;
-import org.eclipse.jetty.util.thread.ThreadPool;
-
-import java.net.InetSocketAddress;
-import java.time.Duration;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-
-public final class VirtualThreadUtils {
-        private VirtualThreadUtils() {
-                throw new IllegalStateException("This is a static utility class and should not be instantiated directly");
-        }
-
-        public static ExecutorService newNamedVirtualThreadsExecutor(String name) {
-                // Based on
-                // https://github.com/eclipse/jetty.project/blob/83154b4ffe4767ef44981598d6c26e6a5d32e57c/jetty-server/src/main/config/etc/jetty-threadpool-virtual-preview.xml
-                return Executors.newThreadPerTaskExecutor(Thread.ofVirtual()
-                                .allowSetThreadLocals(true)
-                                .inheritInheritableThreadLocals(false)
-                                .name(name + "-virtual-", 0)
-                                .factory());
-        }
-
-        public static ThreadPool newThreadPoolWithVirtualThreadsExecutor(String name) {
-                // Based on
-                // https://github.com/eclipse/jetty.project/blob/83154b4ffe4767ef44981598d6c26e6a5d32e57c/jetty-server/src/main/config/etc/jetty-threadpool-virtual-preview.xml
-                int timeout = (int) Duration.ofMinutes(1).toMillis();
-                var threadPool = new QueuedThreadPool(200, 10, timeout, -1, null, null);
-                threadPool.setName(name);
-                threadPool.setDetailedDump(false);
-                threadPool.setVirtualThreadsExecutor(newNamedVirtualThreadsExecutor(name));
-                return threadPool;
-        }
-
-        public static Server newServerWithVirtualThreadsThreadPool(String name, InetSocketAddress listenAddress) {
-                var server = new Server(newThreadPoolWithVirtualThreadsExecutor(name));
-                var connector = new ServerConnector(server);
-                try {
-                        connector.setHost(listenAddress.getHostName());
-                        connector.setPort(listenAddress.getPort());
-                        server.addConnector(connector);
-                } catch (Exception e) {
-                        connector.close();
-                        throw e;
-                }
-                return server;
-        }
-}
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/config/BackendConfig.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/config/BackendConfig.java
index 2e864998..807b789c 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/config/BackendConfig.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/config/BackendConfig.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.config;
 
 import com.google.gson.annotations.SerializedName;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/config/BackendConfigServlet.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/config/BackendConfigServlet.java
index f314a9fa..a2f04e34 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/config/BackendConfigServlet.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/config/BackendConfigServlet.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.config;
 
 import com.google.gson.Gson;
@@ -29,7 +34,7 @@ public class BackendConfigServlet extends HttpServlet {
         }
 
         @Override
-        protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
                 resp.setStatus(HttpStatus.OK_200);
                 resp.setContentType("application/json");
                 var writer = resp.getWriter();
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/occurrences/ProblemOccurrencesService.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/occurrences/ProblemOccurrencesService.java
index d32bbb54..34117384 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/occurrences/ProblemOccurrencesService.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/occurrences/ProblemOccurrencesService.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.occurrences;
 
 import org.eclipse.emf.ecore.EObject;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/VirtualThreadExecutorServiceProvider.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/VirtualThreadExecutorServiceProvider.java
deleted file mode 100644
index abbcbd53..00000000
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/VirtualThreadExecutorServiceProvider.java
+++ /dev/null
@@ -1,16 +0,0 @@
-package tools.refinery.language.web.xtext;
-
-import org.eclipse.xtext.ide.ExecutorServiceProvider;
-import tools.refinery.language.web.VirtualThreadUtils;
-
-import java.util.concurrent.ExecutorService;
-
-public class VirtualThreadExecutorServiceProvider extends ExecutorServiceProvider {
-        private static final String THREAD_POOL_NAME = "xtextWeb";
-
-        @Override
-        protected ExecutorService createInstance(String key) {
-                var name = key == null ? THREAD_POOL_NAME : THREAD_POOL_NAME + "-" + key;
-                return VirtualThreadUtils.newNamedVirtualThreadsExecutor(name);
-        }
-}
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/PongResult.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/PongResult.java
index fe510f51..27b2e04e 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/PongResult.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/PongResult.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server;
 
 import java.util.Objects;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/ResponseHandler.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/ResponseHandler.java
index 2a85afe3..3069c2dd 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/ResponseHandler.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/ResponseHandler.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server;
 
 import tools.refinery.language.web.xtext.server.message.XtextWebResponse;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/ResponseHandlerException.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/ResponseHandlerException.java
index b686d33a..366ef0a7 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/ResponseHandlerException.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/ResponseHandlerException.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server;
 
 import java.io.Serial;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/SubscribingServiceContext.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/SubscribingServiceContext.java
index 78e00a9e..04212b84 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/SubscribingServiceContext.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/SubscribingServiceContext.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server;
 
 import java.util.Set;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/TransactionExecutor.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/TransactionExecutor.java
index 7bb11d2e..0135d8f5 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/TransactionExecutor.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/TransactionExecutor.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server;
 
 import com.google.common.base.Strings;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebErrorKind.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebErrorKind.java
index f74bae74..6f4f265c 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebErrorKind.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebErrorKind.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server.message;
 
 import com.google.gson.annotations.SerializedName;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebErrorResponse.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebErrorResponse.java
index 01d78c31..af38ad70 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebErrorResponse.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebErrorResponse.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server.message;
 
 import java.util.Objects;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebOkResponse.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebOkResponse.java
index 8af27247..73527ee5 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebOkResponse.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebOkResponse.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server.message;
 
 import java.util.Objects;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebPushMessage.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebPushMessage.java
index c9432e1c..e9ff87c4 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebPushMessage.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebPushMessage.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server.message;
 
 import java.util.Objects;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebRequest.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebRequest.java
index 959749f8..ff788e94 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebRequest.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebRequest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server.message;
 
 import java.util.Map;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebResponse.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebResponse.java
index 3bd13047..61444c99 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebResponse.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/message/XtextWebResponse.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server.message;
 
 public sealed interface XtextWebResponse permits XtextWebOkResponse,XtextWebErrorResponse,XtextWebPushMessage {
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PrecomputationListener.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PrecomputationListener.java
index 79a284db..110c8f52 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PrecomputationListener.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PrecomputationListener.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server.push;
 
 import org.eclipse.xtext.web.server.IServiceResult;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushServiceDispatcher.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushServiceDispatcher.java
index c7b8108d..4c9135c8 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushServiceDispatcher.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushServiceDispatcher.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server.push;
 
 import org.eclipse.xtext.web.server.IServiceContext;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushWebDocument.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushWebDocument.java
index 906b9e30..56fd12c9 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushWebDocument.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushWebDocument.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server.push;
 
 import java.util.ArrayList;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushWebDocumentAccess.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushWebDocumentAccess.java
index b3666a86..d9e548cd 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushWebDocumentAccess.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushWebDocumentAccess.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server.push;
 
 import org.eclipse.xtext.service.OperationCanceledManager;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushWebDocumentProvider.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushWebDocumentProvider.java
index b6f04748..b6f4fb43 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushWebDocumentProvider.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/server/push/PushWebDocumentProvider.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.server.push;
 
 import org.eclipse.xtext.web.server.IServiceContext;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/SimpleServiceContext.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/SimpleServiceContext.java
index 43e37160..fee1141d 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/SimpleServiceContext.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/SimpleServiceContext.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.servlet;
 
 import java.util.Map;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/SimpleSession.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/SimpleSession.java
index 09c055a2..bc60c282 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/SimpleSession.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/SimpleSession.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.servlet;
 
 import java.util.HashMap;
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/XtextStatusCode.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/XtextStatusCode.java
index 0cd229e8..caa98e84 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/XtextStatusCode.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/XtextStatusCode.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.servlet;
 
 public final class XtextStatusCode {
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/XtextWebSocket.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/XtextWebSocket.java
index 1d9e0463..043d318c 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/XtextWebSocket.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/XtextWebSocket.java
@@ -1,12 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.servlet;
 
 import com.google.gson.Gson;
 import com.google.gson.JsonIOException;
 import com.google.gson.JsonParseException;
-import org.eclipse.jetty.ee10.websocket.api.Session;
-import org.eclipse.jetty.ee10.websocket.api.StatusCode;
-import org.eclipse.jetty.ee10.websocket.api.WriteCallback;
-import org.eclipse.jetty.ee10.websocket.api.annotations.*;
+import org.eclipse.jetty.websocket.api.Callback;
+import org.eclipse.jetty.websocket.api.Session;
+import org.eclipse.jetty.websocket.api.StatusCode;
+import org.eclipse.jetty.websocket.api.annotations.*;
 import org.eclipse.xtext.resource.IResourceServiceProvider;
 import org.eclipse.xtext.web.server.ISession;
 import org.slf4j.Logger;
@@ -20,7 +25,7 @@ import tools.refinery.language.web.xtext.server.message.XtextWebResponse;
 import java.io.Reader;
 
 @WebSocket
-public class XtextWebSocket implements WriteCallback, ResponseHandler {
+public class XtextWebSocket implements ResponseHandler {
         private static final Logger LOG = LoggerFactory.getLogger(XtextWebSocket.class);
 
         private final Gson gson = new Gson();
@@ -38,13 +43,13 @@ public class XtextWebSocket implements WriteCallback, ResponseHandler {
                 this(new TransactionExecutor(session, resourceServiceProviderRegistry));
         }
 
-        @OnWebSocketConnect
-        public void onConnect(Session webSocketSession) {
+        @OnWebSocketOpen
+        public void onOpen(Session webSocketSession) {
                 if (this.webSocketSession != null) {
                         LOG.error("Websocket session onConnect when already connected");
                         return;
                 }
-                LOG.debug("New websocket connection from {}", webSocketSession.getRemoteAddress());
+                LOG.debug("New websocket connection from {}", webSocketSession.getRemoteSocketAddress());
                 this.webSocketSession = webSocketSession;
         }
 
@@ -55,10 +60,10 @@ public class XtextWebSocket implements WriteCallback, ResponseHandler {
                         return;
                 }
                 if (statusCode == StatusCode.NORMAL || statusCode == StatusCode.SHUTDOWN) {
-                        LOG.debug("{} closed connection normally: {}", webSocketSession.getRemoteAddress(), reason);
+                        LOG.debug("{} closed connection normally: {}", webSocketSession.getRemoteSocketAddress(), reason);
                 } else {
-                        LOG.warn("{} closed connection with status code {}: {}", webSocketSession.getRemoteAddress(), statusCode,
-                                        reason);
+                        LOG.warn("{} closed connection with status code {}: {}", webSocketSession.getRemoteSocketAddress(),
+                                        statusCode, reason);
                 }
                 webSocketSession = null;
         }
@@ -68,7 +73,7 @@ public class XtextWebSocket implements WriteCallback, ResponseHandler {
                 if (webSocketSession == null) {
                         return;
                 }
-                LOG.error("Internal websocket error in connection from" + webSocketSession.getRemoteAddress(), error);
+                LOG.error("Internal websocket error in connection from" + webSocketSession.getRemoteSocketAddress(), error);
         }
 
         @OnWebSocketMessage
@@ -81,14 +86,14 @@ public class XtextWebSocket implements WriteCallback, ResponseHandler {
                 try {
                         request = gson.fromJson(reader, XtextWebRequest.class);
                 } catch (JsonIOException e) {
-                        LOG.error("Cannot read from websocket from" + webSocketSession.getRemoteAddress(), e);
+                        LOG.error("Cannot read from websocket from" + webSocketSession.getRemoteSocketAddress(), e);
                         if (webSocketSession.isOpen()) {
-                                webSocketSession.close(StatusCode.SERVER_ERROR, "Cannot read payload");
+                                webSocketSession.close(StatusCode.SERVER_ERROR, "Cannot read payload", Callback.NOOP);
                         }
                         return;
                 } catch (JsonParseException e) {
-                        LOG.warn("Malformed websocket request from" + webSocketSession.getRemoteAddress(), e);
-                        webSocketSession.close(XtextStatusCode.INVALID_JSON, "Invalid JSON payload");
+                        LOG.warn("Malformed websocket request from" + webSocketSession.getRemoteSocketAddress(), e);
+                        webSocketSession.close(XtextStatusCode.INVALID_JSON, "Invalid JSON payload", Callback.NOOP);
                         return;
                 }
                 try {
@@ -96,7 +101,7 @@ public class XtextWebSocket implements WriteCallback, ResponseHandler {
                 } catch (ResponseHandlerException e) {
                         LOG.warn("Cannot write websocket response", e);
                         if (webSocketSession.isOpen()) {
-                                webSocketSession.close(StatusCode.SERVER_ERROR, "Cannot write response");
+                                webSocketSession.close(StatusCode.SERVER_ERROR, "Cannot write response", Callback.NOOP);
                         }
                 }
         }
@@ -107,15 +112,14 @@ public class XtextWebSocket implements WriteCallback, ResponseHandler {
                         throw new ResponseHandlerException("Trying to send message when websocket is disconnected");
                 }
                 var responseString = gson.toJson(response);
-                webSocketSession.getRemote().sendPartialString(responseString, true, this);
+                webSocketSession.sendText(responseString, Callback.from(() -> {}, this::writeFailed));
         }
 
-        @Override
         public void writeFailed(Throwable x) {
                 if (webSocketSession == null) {
                         LOG.error("Cannot complete async write to disconnected websocket", x);
                         return;
                 }
-                LOG.warn("Cannot complete async write to websocket " + webSocketSession.getRemoteAddress(), x);
+                LOG.warn("Cannot complete async write to websocket " + webSocketSession.getRemoteSocketAddress(), x);
         }
 }
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/XtextWebSocketServlet.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/XtextWebSocketServlet.java
index 9a32b937..5e4fb0ce 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/XtextWebSocketServlet.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/XtextWebSocketServlet.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.servlet;
 
 import jakarta.servlet.ServletConfig;
diff --git a/subprojects/language-web/src/test/java/tools/refinery/language/web/ProblemWebSocketServletIntegrationTest.java b/subprojects/language-web/src/test/java/tools/refinery/language/web/ProblemWebSocketServletIntegrationTest.java
index ecbefc4f..927eeab1 100644
--- a/subprojects/language-web/src/test/java/tools/refinery/language/web/ProblemWebSocketServletIntegrationTest.java
+++ b/subprojects/language-web/src/test/java/tools/refinery/language/web/ProblemWebSocketServletIntegrationTest.java
@@ -1,20 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web;
 
 import org.eclipse.jetty.ee10.servlet.ServletContextHandler;
 import org.eclipse.jetty.ee10.servlet.ServletHolder;
-import org.eclipse.jetty.ee10.websocket.api.Session;
-import org.eclipse.jetty.ee10.websocket.api.StatusCode;
-import org.eclipse.jetty.ee10.websocket.api.annotations.WebSocket;
-import org.eclipse.jetty.ee10.websocket.api.exceptions.UpgradeException;
-import org.eclipse.jetty.ee10.websocket.client.ClientUpgradeRequest;
-import org.eclipse.jetty.ee10.websocket.client.WebSocketClient;
 import org.eclipse.jetty.ee10.websocket.server.config.JettyWebSocketServletContainerInitializer;
 import org.eclipse.jetty.http.HttpHeader;
 import org.eclipse.jetty.http.HttpStatus;
 import org.eclipse.jetty.server.Server;
+import org.eclipse.jetty.util.thread.QueuedThreadPool;
+import org.eclipse.jetty.websocket.api.Callback;
+import org.eclipse.jetty.websocket.api.Session;
+import org.eclipse.jetty.websocket.api.StatusCode;
+import org.eclipse.jetty.websocket.api.annotations.WebSocket;
+import org.eclipse.jetty.websocket.api.exceptions.UpgradeException;
+import org.eclipse.jetty.websocket.client.ClientUpgradeRequest;
+import org.eclipse.jetty.websocket.client.WebSocketClient;
 import org.eclipse.xtext.testing.GlobalRegistries;
 import org.eclipse.xtext.testing.GlobalRegistries.GlobalStateMemento;
-import org.junit.jupiter.api.*;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.TestInfo;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
 import tools.refinery.language.web.tests.WebSocketIntegrationTestClient;
@@ -86,23 +96,34 @@ class ProblemWebSocketServletIntegrationTest {
                 assertThat(responses, hasSize(5));
                 assertThat(responses.get(0), equalTo("{\"id\":\"foo\",\"response\":{\"stateId\":\"-80000000\"}}"));
                 assertThat(responses.get(1), startsWith(
-                                "{\"resource\":\"test.problem\",\"stateId\":\"-80000000\",\"service\":\"highlight\",\"push\":{\"regions\":["));
+                                "{\"resource\":\"test.problem\",\"stateId\":\"-80000000\",\"service\":\"highlight\"," +
+                                                "\"push\":{\"regions\":["));
                 assertThat(responses.get(2), equalTo(
-                                "{\"resource\":\"test.problem\",\"stateId\":\"-80000000\",\"service\":\"validate\",\"push\":{\"issues\":[]}}"));
+                                "{\"resource\":\"test.problem\",\"stateId\":\"-80000000\",\"service\":\"validate\"," +
+                                                "\"push\":{\"issues\":[]}}"));
                 assertThat(responses.get(3), equalTo("{\"id\":\"bar\",\"response\":{\"stateId\":\"-7fffffff\"}}"));
                 assertThat(responses.get(4), startsWith(
-                                "{\"resource\":\"test.problem\",\"stateId\":\"-7fffffff\",\"service\":\"highlight\",\"push\":{\"regions\":["));
+                                "{\"resource\":\"test.problem\",\"stateId\":\"-7fffffff\",\"service\":\"highlight\"," +
+                                                "\"push\":{\"regions\":["));
         }
 
         @WebSocket
         public static class UpdateTestClient extends WebSocketIntegrationTestClient {
                 @Override
-                protected void arrange(Session session, int responsesReceived) throws IOException {
+                protected void arrange(Session session, int responsesReceived) {
                         switch (responsesReceived) {
-                        case 0 -> session.getRemote().sendString(
-                                        "{\"id\":\"foo\",\"request\":{\"resource\":\"test.problem\",\"serviceType\":\"update\",\"fullText\":\"class Person.\n\"}}");
-                        case 3 -> session.getRemote().sendString(
-                                        "{\"id\":\"bar\",\"request\":{\"resource\":\"test.problem\",\"serviceType\":\"update\",\"requiredStateId\":\"-80000000\",\"deltaText\":\"indiv q.\nnode(q).\n\",\"deltaOffset\":\"0\",\"deltaReplaceLength\":\"0\"}}");
+                        case 0 -> session.sendText(
+                                        "{\"id\":\"foo\",\"request\":{\"resource\":\"test.problem\",\"serviceType\":\"update\"," +
+                                                        "\"fullText\":\"class Person.\n\"}}",
+                                        Callback.NOOP
+                        );
+                        case 3 -> //noinspection TextBlockMigration
+                                        session.sendText(
+                                        "{\"id\":\"bar\",\"request\":{\"resource\":\"test.problem\",\"serviceType\":\"update\"," +
+                                                        "\"requiredStateId\":\"-80000000\",\"deltaText\":\"indiv q.\nnode(q).\n\"," +
+                                                        "\"deltaOffset\":\"0\",\"deltaReplaceLength\":\"0\"}}",
+                                        Callback.NOOP
+                        );
                         case 5 -> session.close();
                         }
                 }
@@ -152,13 +173,13 @@ class ProblemWebSocketServletIntegrationTest {
         @WebSocket
         public static class InvalidJsonTestClient extends WebSocketIntegrationTestClient {
                 @Override
-                protected void arrange(Session session, int responsesReceived) throws IOException {
-                        session.getRemote().sendString("<invalid json>");
+                protected void arrange(Session session, int responsesReceived) {
+                        session.sendText("<invalid json>", Callback.NOOP);
                 }
         }
 
         @ParameterizedTest(name = "validOriginTest(\"{0}\")")
-        @ValueSource(strings = { "https://refinery.example", "https://refinery.example:443", "HTTPS://REFINERY.EXAMPLE" })
+        @ValueSource(strings = {"https://refinery.example", "https://refinery.example:443", "HTTPS://REFINERY.EXAMPLE"})
         void validOriginTest(String origin) {
                 startServer("https://refinery.example,https://refinery.example:443");
                 var clientSocket = new CloseImmediatelyTestClient();
@@ -188,7 +209,8 @@ class ProblemWebSocketServletIntegrationTest {
         private void startServer(String allowedOrigins) {
                 var testName = getClass().getSimpleName() + "-" + testInfo.getDisplayName();
                 var listenAddress = new InetSocketAddress(HOSTNAME, serverPort);
-                server = VirtualThreadUtils.newServerWithVirtualThreadsThreadPool(testName, listenAddress);
+                server = new Server(listenAddress);
+                ((QueuedThreadPool) server.getThreadPool()).setName(testName);
                 var handler = new ServletContextHandler();
                 var holder = new ServletHolder(ProblemWebSocketServlet.class);
                 if (allowedOrigins != null) {
diff --git a/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/AwaitTerminationExecutorServiceProvider.java b/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/AwaitTerminationExecutorServiceProvider.java
index c634e8fc..52acee6d 100644
--- a/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/AwaitTerminationExecutorServiceProvider.java
+++ b/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/AwaitTerminationExecutorServiceProvider.java
@@ -1,14 +1,19 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.tests;
 
 import com.google.inject.Singleton;
-import tools.refinery.language.web.xtext.VirtualThreadExecutorServiceProvider;
+import org.eclipse.xtext.ide.ExecutorServiceProvider;
 
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.ExecutorService;
 
 @Singleton
-public class AwaitTerminationExecutorServiceProvider extends VirtualThreadExecutorServiceProvider {
+public class AwaitTerminationExecutorServiceProvider extends ExecutorServiceProvider {
         private final List<RestartableCachedThreadPool> servicesToShutDown = new ArrayList<>();
 
         @Override
diff --git a/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/ProblemWebInjectorProvider.java b/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/ProblemWebInjectorProvider.java
index 43c12faa..4a5eed95 100644
--- a/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/ProblemWebInjectorProvider.java
+++ b/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/ProblemWebInjectorProvider.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.tests;
 
 import org.eclipse.xtext.ide.ExecutorServiceProvider;
diff --git a/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/RestartableCachedThreadPool.java b/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/RestartableCachedThreadPool.java
index cf805eda..09079aa8 100644
--- a/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/RestartableCachedThreadPool.java
+++ b/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/RestartableCachedThreadPool.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.tests;
 
 import com.google.inject.Provider;
diff --git a/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/WebSocketIntegrationTestClient.java b/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/WebSocketIntegrationTestClient.java
index f19c10ca..6ccf1760 100644
--- a/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/WebSocketIntegrationTestClient.java
+++ b/subprojects/language-web/src/test/java/tools/refinery/language/web/tests/WebSocketIntegrationTestClient.java
@@ -1,12 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.tests;
 
-import org.eclipse.jetty.ee10.websocket.api.Session;
-import org.eclipse.jetty.ee10.websocket.api.annotations.OnWebSocketClose;
-import org.eclipse.jetty.ee10.websocket.api.annotations.OnWebSocketConnect;
-import org.eclipse.jetty.ee10.websocket.api.annotations.OnWebSocketError;
-import org.eclipse.jetty.ee10.websocket.api.annotations.OnWebSocketMessage;
+import org.eclipse.jetty.websocket.api.Session;
+import org.eclipse.jetty.websocket.api.annotations.OnWebSocketClose;
+import org.eclipse.jetty.websocket.api.annotations.OnWebSocketError;
+import org.eclipse.jetty.websocket.api.annotations.OnWebSocketMessage;
+import org.eclipse.jetty.websocket.api.annotations.OnWebSocketOpen;
 
-import java.io.IOException;
 import java.time.Duration;
 import java.util.ArrayList;
 import java.util.List;
@@ -14,7 +18,7 @@ import java.util.List;
 import static org.junit.jupiter.api.Assertions.fail;
 
 public abstract class WebSocketIntegrationTestClient {
-        private static final long TIMEOUT_MILLIS = Duration.ofSeconds(1).toMillis();
+        private static final long TIMEOUT_MILLIS = Duration.ofSeconds(10).toMillis();
 
         private boolean finished = false;
 
@@ -34,8 +38,8 @@ public abstract class WebSocketIntegrationTestClient {
                 return responses;
         }
 
-        @OnWebSocketConnect
-        public void onConnect(Session session) {
+        @OnWebSocketOpen
+        public void onOpen(Session session) {
                 arrangeAndCatchErrors(session);
         }
 
@@ -47,7 +51,7 @@ public abstract class WebSocketIntegrationTestClient {
                 }
         }
 
-        protected abstract void arrange(Session session, int responsesReceived) throws IOException;
+        protected abstract void arrange(Session session, int responsesReceived);
 
         @OnWebSocketClose
         public void onClose(int statusCode, String reason) {
diff --git a/subprojects/language-web/src/test/java/tools/refinery/language/web/xtext/servlet/TransactionExecutorTest.java b/subprojects/language-web/src/test/java/tools/refinery/language/web/xtext/servlet/TransactionExecutorTest.java
index 17f1ff5c..841bacd3 100644
--- a/subprojects/language-web/src/test/java/tools/refinery/language/web/xtext/servlet/TransactionExecutorTest.java
+++ b/subprojects/language-web/src/test/java/tools/refinery/language/web/xtext/servlet/TransactionExecutorTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.web.xtext.servlet;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/build.gradle b/subprojects/language/build.gradle
deleted file mode 100644
index 654558e3..00000000
--- a/subprojects/language/build.gradle
+++ /dev/null
@@ -1,73 +0,0 @@
-plugins {
-        id 'refinery-java-library'
-        id 'refinery-java-test-fixtures'
-        id 'refinery-mwe2'
-        id 'refinery-sonarqube'
-        id 'refinery-xtext-conventions'
-}
-
-dependencies {
-        api platform(libs.xtext.bom)
-        api libs.ecore
-        api libs.xtext.core
-        api libs.xtext.xbase
-        api project(':refinery-language-model')
-        testFixturesApi libs.xtext.testing
-        mwe2 libs.xtext.generator
-        mwe2 libs.xtext.generator.antlr
-}
-
-sourceSets {
-        testFixtures {
-                java.srcDirs += ['src/testFixtures/xtext-gen']
-                resources.srcDirs += ['src/testFixtures/xtext-gen']
-        }
-}
-
-tasks.named('jar') {
-        from(sourceSets.main.allSource) {
-                include '**/*.xtext'
-        }
-}
-
-def generateXtextLanguage = tasks.register('generateXtextLanguage', JavaExec) {
-        mainClass = 'org.eclipse.emf.mwe2.launch.runtime.Mwe2Launcher'
-        classpath = configurations.mwe2
-        inputs.file 'src/main/java/tools/refinery/language/GenerateProblem.mwe2'
-        inputs.file 'src/main/java/tools/refinery/language/Problem.xtext'
-        outputs.dir 'src/main/xtext-gen'
-        outputs.dir 'src/testFixtures/xtext-gen'
-        outputs.dir '../language-ide/src/main/xtext-gen'
-        outputs.dir '../language-web/src/main/xtext-gen'
-        args += 'src/main/java/tools/refinery/language/GenerateProblem.mwe2'
-        args += '-p'
-        args += "rootPath=/${projectDir}/.."
-}
-
-for (taskName in [
-                'compileJava',
-                'processResources',
-                'processTestFixturesResources',
-                'generateEclipseSourceFolders'
-        ]) {
-        tasks.named(taskName) {
-                dependsOn generateXtextLanguage
-        }
-}
-
-tasks.named('clean') {
-        delete 'src/main/xtext-gen'
-        delete 'src/testFixtures/xtext-gen'
-        delete '../language-ide/src/main/xtext-gen'
-        delete '../language-web/src/main/xtext-gen'
-}
-
-sonarqube.properties {
-        properties['sonar.exclusions'] += [
-                'src/testFixtures/xtext-gen/**',
-        ]
-}
-
-eclipse.project.natures += [
-        'org.eclipse.xtext.ui.shared.xtextNature'
-]
diff --git a/subprojects/language/build.gradle.kts b/subprojects/language/build.gradle.kts
new file mode 100644
index 00000000..bac1e586
--- /dev/null
+++ b/subprojects/language/build.gradle.kts
@@ -0,0 +1,101 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+import tools.refinery.gradle.utils.SonarPropertiesUtils
+
+plugins {
+        id("tools.refinery.gradle.java-library")
+        id("tools.refinery.gradle.java-test-fixtures")
+        id("tools.refinery.gradle.mwe2")
+        id("tools.refinery.gradle.sonarqube")
+        id("tools.refinery.gradle.xtext-generated")
+}
+
+val generatedIdeSources: Configuration by configurations.creating {
+        isCanBeConsumed = true
+        isCanBeResolved = false
+}
+
+val generatedWebSources: Configuration by configurations.creating {
+        isCanBeConsumed = true
+        isCanBeResolved = false
+}
+
+dependencies {
+        api(platform(libs.xtext.bom))
+        api(libs.ecore)
+        api(libs.xtext.core)
+        api(libs.xtext.xbase)
+        api(project(":refinery-language-model"))
+        testFixturesApi(libs.xtext.testing)
+        mwe2(libs.xtext.generator)
+        mwe2(libs.xtext.generator.antlr)
+}
+
+sourceSets {
+        testFixtures {
+                java.srcDir("src/testFixtures/xtext-gen")
+                resources.srcDir("src/testFixtures/xtext-gen")
+        }
+}
+
+val generateXtextLanguage by tasks.registering(JavaExec::class) {
+        mainClass.set("org.eclipse.emf.mwe2.launch.runtime.Mwe2Launcher")
+        classpath(configurations.mwe2)
+        inputs.file("src/main/java/tools/refinery/language/GenerateProblem.mwe2")
+        inputs.file("src/main/java/tools/refinery/language/Problem.xtext")
+        inputs.file("../language-model/src/main/resources/model/problem.ecore")
+        inputs.file("../language-model/src/main/resources/model/problem.genmodel")
+        outputs.dir("src/main/xtext-gen")
+        outputs.dir("src/testFixtures/xtext-gen")
+        outputs.dir("$buildDir/generated/sources/xtext/ide")
+        outputs.dir("$buildDir/generated/sources/xtext/web")
+        args("src/main/java/tools/refinery/language/GenerateProblem.mwe2", "-p", "rootPath=/$projectDir/..")
+}
+
+tasks {
+        jar {
+                from(sourceSets.main.map { it.allSource }) {
+                        include("**/*.xtext")
+                }
+        }
+
+        syncXtextGeneratedSources {
+                // We generate Xtext runtime sources directly to {@code src/main/xtext-gen}, so there is no need to copy them
+                // from an artifact. We expose the {@code generatedIdeSources} and {@code generatedWebSources} artifacts to
+                // sibling IDE and web projects which can use this task to consume them and copy the appropriate sources to
+                // their own {@code src/main/xtext-gen} directory.
+                enabled = false
+        }
+
+        for (taskName in listOf("compileJava", "processResources", "compileTestFixturesJava",
+                        "processTestFixturesResources", "generateEclipseSourceFolders")) {
+                named(taskName) {
+                        dependsOn(generateXtextLanguage)
+                }
+        }
+
+        clean {
+                delete("src/main/xtext-gen")
+                delete("src/testFixtures/xtext-gen")
+        }
+}
+
+artifacts {
+        add(generatedIdeSources.name, file("$buildDir/generated/sources/xtext/ide")) {
+                builtBy(generateXtextLanguage)
+        }
+
+        add(generatedWebSources.name, file("$buildDir/generated/sources/xtext/web")) {
+                builtBy(generateXtextLanguage)
+        }
+}
+
+sonarqube.properties {
+        SonarPropertiesUtils.addToList(properties, "sonar.exclusions", "src/textFixtures/xtext-gen/**")
+}
+
+eclipse.project.natures.plusAssign("org.eclipse.xtext.ui.shared.xtextNature")
diff --git a/subprojects/language/src/main/java/tools/refinery/language/GenerateProblem.mwe2 b/subprojects/language/src/main/java/tools/refinery/language/GenerateProblem.mwe2
index 21ff456e..59eba8f7 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/GenerateProblem.mwe2
+++ b/subprojects/language/src/main/java/tools/refinery/language/GenerateProblem.mwe2
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 module tools.refinery.language.GenerateProblem
 
 import org.eclipse.xtext.xtext.generator.*
@@ -11,16 +16,28 @@ Workflow {
                         project = StandardProjectConfig {
                                 baseName = 'language'
                                 rootPath = rootPath
+                                runtime = {
+                                        // Do not generate new files into src/main/java
+                                        src = null
+                                }
                                 runtimeTest = {
                                         enabled = true
-                                        srcGen = 'src/testFixtures/xtext-gen'
+                                        // Only generate the xtext-gen files and leave the rest of the project alone
+                                        root = null
+                                        srcGen = '${rootPath}/language/src/testFixtures/xtext-gen'
                                 }
                                 genericIde = {
                                         name = 'language-ide'
+                                        // Only generate the xtext-gen files and leave the rest of the project alone
+                                        root = null
+                                        srcGen = "${rootPath}/language/build/generated/sources/xtext/ide"
                                 }
                                 web = {
                                         enabled = true
                                         name = 'language-web'
+                                        // Only generate the xtext-gen files and leave the rest of the project alone
+                                        root = null
+                                        srcGen = "${rootPath}/language/build/generated/sources/xtext/web"
                                 }
                                 mavenLayout = true
                         }
@@ -55,7 +72,7 @@ Workflow {
                         }
                         webSupport = {
                                 // We only generate the {@code AbstractProblemWebModule},
-                                // because we write our own integration code for CodeMirror 6. 
+                                // because we write our own integration code for CodeMirror 6.
                                 framework = 'codemirror'
                                 generateHtmlExample = false
                                 generateJettyLauncher = false
diff --git a/subprojects/language/src/main/java/tools/refinery/language/Problem.xtext b/subprojects/language/src/main/java/tools/refinery/language/Problem.xtext
index 187ebf1f..9e330347 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/Problem.xtext
+++ b/subprojects/language/src/main/java/tools/refinery/language/Problem.xtext
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 grammar tools.refinery.language.Problem with org.eclipse.xtext.common.Terminals
 
 import "http://www.eclipse.org/emf/2002/Ecore" as ecore
diff --git a/subprojects/language/src/main/java/tools/refinery/language/ProblemRuntimeModule.java b/subprojects/language/src/main/java/tools/refinery/language/ProblemRuntimeModule.java
index 5efcdc81..2636a8ee 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/ProblemRuntimeModule.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/ProblemRuntimeModule.java
@@ -1,4 +1,10 @@
 /*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+/*
  * generated by Xtext 2.25.0
  */
 package tools.refinery.language;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/ProblemStandaloneSetup.java b/subprojects/language/src/main/java/tools/refinery/language/ProblemStandaloneSetup.java
index 41c96114..639d6778 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/ProblemStandaloneSetup.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/ProblemStandaloneSetup.java
@@ -1,4 +1,10 @@
 /*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+/*
  * generated by Xtext 2.25.0
  */
 package tools.refinery.language;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/conversion/ProblemValueConverterService.java b/subprojects/language/src/main/java/tools/refinery/language/conversion/ProblemValueConverterService.java
index 508688ed..afbc367e 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/conversion/ProblemValueConverterService.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/conversion/ProblemValueConverterService.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.conversion;
 
 import org.eclipse.xtext.common.services.DefaultTerminalConverters;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/conversion/UpperBoundValueConverter.java b/subprojects/language/src/main/java/tools/refinery/language/conversion/UpperBoundValueConverter.java
index be0d15ad..4886757d 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/conversion/UpperBoundValueConverter.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/conversion/UpperBoundValueConverter.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.conversion;
 
 import org.eclipse.xtext.conversion.ValueConverterException;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/formatting2/ProblemFormatter.java b/subprojects/language/src/main/java/tools/refinery/language/formatting2/ProblemFormatter.java
index 797535ea..55a5ac20 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/formatting2/ProblemFormatter.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/formatting2/ProblemFormatter.java
@@ -1,4 +1,10 @@
 /*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+/*
  * generated by Xtext 2.26.0.M2
  */
 package tools.refinery.language.formatting2;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/naming/NamingUtil.java b/subprojects/language/src/main/java/tools/refinery/language/naming/NamingUtil.java
index e959be74..1647d4e7 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/naming/NamingUtil.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/naming/NamingUtil.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.naming;
 
 import java.util.regex.Pattern;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/naming/ProblemQualifiedNameConverter.java b/subprojects/language/src/main/java/tools/refinery/language/naming/ProblemQualifiedNameConverter.java
index 5453906f..74b4e208 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/naming/ProblemQualifiedNameConverter.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/naming/ProblemQualifiedNameConverter.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.naming;
 
 import org.eclipse.xtext.naming.IQualifiedNameConverter;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/parser/antlr/IdentifierTokenProvider.java b/subprojects/language/src/main/java/tools/refinery/language/parser/antlr/IdentifierTokenProvider.java
index ab133a90..306a86fc 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/parser/antlr/IdentifierTokenProvider.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/parser/antlr/IdentifierTokenProvider.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.parser.antlr;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/parser/antlr/ProblemTokenSource.java b/subprojects/language/src/main/java/tools/refinery/language/parser/antlr/ProblemTokenSource.java
index 0b4e7185..5b91a6cc 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/parser/antlr/ProblemTokenSource.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/parser/antlr/ProblemTokenSource.java
@@ -1,4 +1,10 @@
 /*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+/*
  * generated by Xtext 2.29.0.M2
  */
 package tools.refinery.language.parser.antlr;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/parser/antlr/TokenSourceInjectingProblemParser.java b/subprojects/language/src/main/java/tools/refinery/language/parser/antlr/TokenSourceInjectingProblemParser.java
index 0cdd38d8..fe4c0bc7 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/parser/antlr/TokenSourceInjectingProblemParser.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/parser/antlr/TokenSourceInjectingProblemParser.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.parser.antlr;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/resource/DerivedVariableComputer.java b/subprojects/language/src/main/java/tools/refinery/language/resource/DerivedVariableComputer.java
index 6176b0c4..07c5da41 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/resource/DerivedVariableComputer.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/resource/DerivedVariableComputer.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.resource;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/resource/ImplicitVariableScope.java b/subprojects/language/src/main/java/tools/refinery/language/resource/ImplicitVariableScope.java
index b0ac2ab6..e97c8287 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/resource/ImplicitVariableScope.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/resource/ImplicitVariableScope.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.resource;
 
 import org.eclipse.emf.ecore.EObject;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/resource/NodeNameCollector.java b/subprojects/language/src/main/java/tools/refinery/language/resource/NodeNameCollector.java
index 419be0d3..e5deca4d 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/resource/NodeNameCollector.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/resource/NodeNameCollector.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.resource;
 
 import com.google.common.collect.ImmutableSet;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemDerivedStateComputer.java b/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemDerivedStateComputer.java
index 8d3a552a..b145ef27 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemDerivedStateComputer.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemDerivedStateComputer.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.resource;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemLocationInFileProvider.java b/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemLocationInFileProvider.java
index df822987..1fe2df89 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemLocationInFileProvider.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemLocationInFileProvider.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.resource;
 
 import org.eclipse.emf.ecore.EObject;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescriptionStrategy.java b/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescriptionStrategy.java
index 1a0b73a8..630be379 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescriptionStrategy.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescriptionStrategy.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.resource;
 
 import org.eclipse.emf.ecore.EObject;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/resource/ReferenceCounter.java b/subprojects/language/src/main/java/tools/refinery/language/resource/ReferenceCounter.java
index ca20325e..f1be55ee 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/resource/ReferenceCounter.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/resource/ReferenceCounter.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.resource;
 
 import java.util.HashMap;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemGlobalScopeProvider.java b/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemGlobalScopeProvider.java
index b749154c..4d2dd772 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemGlobalScopeProvider.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemGlobalScopeProvider.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.scoping;
 
 import java.util.LinkedHashSet;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemLocalScopeProvider.java b/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemLocalScopeProvider.java
index 61883f0e..229960a0 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemLocalScopeProvider.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemLocalScopeProvider.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.scoping;
 
 import java.util.List;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemScopeProvider.java b/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemScopeProvider.java
index 3ab07496..cf099aba 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemScopeProvider.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemScopeProvider.java
@@ -1,4 +1,10 @@
 /*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+/*
  * generated by Xtext 2.25.0
  */
 package tools.refinery.language.scoping;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/serializer/PreferShortAssertionsProblemSemanticSequencer.java b/subprojects/language/src/main/java/tools/refinery/language/serializer/PreferShortAssertionsProblemSemanticSequencer.java
index 27ce1521..b9cafbc2 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/serializer/PreferShortAssertionsProblemSemanticSequencer.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/serializer/PreferShortAssertionsProblemSemanticSequencer.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.serializer;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/utils/BuiltinSymbols.java b/subprojects/language/src/main/java/tools/refinery/language/utils/BuiltinSymbols.java
index d3777cd3..c8c7fd4a 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/utils/BuiltinSymbols.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/utils/BuiltinSymbols.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.utils;
 
 import tools.refinery.language.model.problem.*;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/utils/CollectedSymbols.java b/subprojects/language/src/main/java/tools/refinery/language/utils/CollectedSymbols.java
index b5682f32..e4e4d07a 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/utils/CollectedSymbols.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/utils/CollectedSymbols.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.utils;
 
 import java.util.Map;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/utils/ContainmentRole.java b/subprojects/language/src/main/java/tools/refinery/language/utils/ContainmentRole.java
index 708e10a9..a43c7dfe 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/utils/ContainmentRole.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/utils/ContainmentRole.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.utils;
 
 import tools.refinery.language.model.problem.PredicateKind;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/utils/NodeInfo.java b/subprojects/language/src/main/java/tools/refinery/language/utils/NodeInfo.java
index c8f47653..0fa7a454 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/utils/NodeInfo.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/utils/NodeInfo.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.utils;
 
 public record NodeInfo(String name, boolean individual) {
diff --git a/subprojects/language/src/main/java/tools/refinery/language/utils/ProblemDesugarer.java b/subprojects/language/src/main/java/tools/refinery/language/utils/ProblemDesugarer.java
index b8200919..738a0896 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/utils/ProblemDesugarer.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/utils/ProblemDesugarer.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.utils;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/utils/ProblemUtil.java b/subprojects/language/src/main/java/tools/refinery/language/utils/ProblemUtil.java
index 1e5164d3..9486dc2a 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/utils/ProblemUtil.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/utils/ProblemUtil.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.utils;
 
 import org.eclipse.emf.common.util.URI;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/utils/RelationInfo.java b/subprojects/language/src/main/java/tools/refinery/language/utils/RelationInfo.java
index 2253d257..1c46fe72 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/utils/RelationInfo.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/utils/RelationInfo.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.utils;
 
 import tools.refinery.language.model.problem.*;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/utils/SymbolCollector.java b/subprojects/language/src/main/java/tools/refinery/language/utils/SymbolCollector.java
index 65167ed6..a4ea1113 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/utils/SymbolCollector.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/utils/SymbolCollector.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.utils;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/main/java/tools/refinery/language/validation/ProblemValidator.java b/subprojects/language/src/main/java/tools/refinery/language/validation/ProblemValidator.java
index 659d882c..88d50c5b 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/validation/ProblemValidator.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/validation/ProblemValidator.java
@@ -1,4 +1,10 @@
 /*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+/*
  * generated by Xtext 2.25.0
  */
 package tools.refinery.language.validation;
diff --git a/subprojects/language/src/main/resources/tools/refinery/language/builtin.problem b/subprojects/language/src/main/resources/tools/refinery/language/builtin.problem
index 06b6da1d..9c1d7669 100644
--- a/subprojects/language/src/main/resources/tools/refinery/language/builtin.problem
+++ b/subprojects/language/src/main/resources/tools/refinery/language/builtin.problem
@@ -1,3 +1,6 @@
+% SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+%
+% SPDX-License-Identifier: EPL-2.0
 problem builtin.
 
 abstract class node {
diff --git a/subprojects/language/src/test/java/tools/refinery/language/tests/ProblemParsingTest.java b/subprojects/language/src/test/java/tools/refinery/language/tests/ProblemParsingTest.java
index 58daa365..c7952369 100644
--- a/subprojects/language/src/test/java/tools/refinery/language/tests/ProblemParsingTest.java
+++ b/subprojects/language/src/test/java/tools/refinery/language/tests/ProblemParsingTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.tests;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/test/java/tools/refinery/language/tests/formatting2/ProblemFormatterTest.java b/subprojects/language/src/test/java/tools/refinery/language/tests/formatting2/ProblemFormatterTest.java
index 6e0802ca..f688d970 100644
--- a/subprojects/language/src/test/java/tools/refinery/language/tests/formatting2/ProblemFormatterTest.java
+++ b/subprojects/language/src/test/java/tools/refinery/language/tests/formatting2/ProblemFormatterTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.tests.formatting2;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/test/java/tools/refinery/language/tests/parser/antlr/IdentifierTokenProviderTest.java b/subprojects/language/src/test/java/tools/refinery/language/tests/parser/antlr/IdentifierTokenProviderTest.java
index abff8d9c..37d38dd9 100644
--- a/subprojects/language/src/test/java/tools/refinery/language/tests/parser/antlr/IdentifierTokenProviderTest.java
+++ b/subprojects/language/src/test/java/tools/refinery/language/tests/parser/antlr/IdentifierTokenProviderTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.tests.parser.antlr;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/test/java/tools/refinery/language/tests/parser/antlr/ProblemTokenSourceTest.java b/subprojects/language/src/test/java/tools/refinery/language/tests/parser/antlr/ProblemTokenSourceTest.java
index cb42d5d0..644744a0 100644
--- a/subprojects/language/src/test/java/tools/refinery/language/tests/parser/antlr/ProblemTokenSourceTest.java
+++ b/subprojects/language/src/test/java/tools/refinery/language/tests/parser/antlr/ProblemTokenSourceTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.tests.parser.antlr;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/test/java/tools/refinery/language/tests/parser/antlr/TransitiveClosureParserTest.java b/subprojects/language/src/test/java/tools/refinery/language/tests/parser/antlr/TransitiveClosureParserTest.java
index 65ceb45f..1180d131 100644
--- a/subprojects/language/src/test/java/tools/refinery/language/tests/parser/antlr/TransitiveClosureParserTest.java
+++ b/subprojects/language/src/test/java/tools/refinery/language/tests/parser/antlr/TransitiveClosureParserTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.tests.parser.antlr;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/test/java/tools/refinery/language/tests/rules/RuleParsingTest.java b/subprojects/language/src/test/java/tools/refinery/language/tests/rules/RuleParsingTest.java
index 72e5e18a..68514bfa 100644
--- a/subprojects/language/src/test/java/tools/refinery/language/tests/rules/RuleParsingTest.java
+++ b/subprojects/language/src/test/java/tools/refinery/language/tests/rules/RuleParsingTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.tests.rules;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/test/java/tools/refinery/language/tests/scoping/NodeScopingTest.java b/subprojects/language/src/test/java/tools/refinery/language/tests/scoping/NodeScopingTest.java
index fa462691..734bfcd1 100644
--- a/subprojects/language/src/test/java/tools/refinery/language/tests/scoping/NodeScopingTest.java
+++ b/subprojects/language/src/test/java/tools/refinery/language/tests/scoping/NodeScopingTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.tests.scoping;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/test/java/tools/refinery/language/tests/serializer/ProblemSerializerTest.java b/subprojects/language/src/test/java/tools/refinery/language/tests/serializer/ProblemSerializerTest.java
index 4a18704a..3f3a081f 100644
--- a/subprojects/language/src/test/java/tools/refinery/language/tests/serializer/ProblemSerializerTest.java
+++ b/subprojects/language/src/test/java/tools/refinery/language/tests/serializer/ProblemSerializerTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.tests.serializer;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/test/java/tools/refinery/language/tests/utils/SymbolCollectorTest.java b/subprojects/language/src/test/java/tools/refinery/language/tests/utils/SymbolCollectorTest.java
index af6de37f..d200eeff 100644
--- a/subprojects/language/src/test/java/tools/refinery/language/tests/utils/SymbolCollectorTest.java
+++ b/subprojects/language/src/test/java/tools/refinery/language/tests/utils/SymbolCollectorTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.tests.utils;
 
 import com.google.inject.Inject;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/ProblemNavigationUtil.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/ProblemNavigationUtil.java
index 5761935b..d92011a9 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/ProblemNavigationUtil.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/ProblemNavigationUtil.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import java.util.List;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/ProblemParseHelper.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/ProblemParseHelper.java
index 5e044a94..6f6a87f7 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/ProblemParseHelper.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/ProblemParseHelper.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import org.eclipse.xtext.testing.util.ParseHelper;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAction.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAction.java
index d176727b..3a49a0b9 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAction.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAction.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.Action;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedArgument.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedArgument.java
index 9e4c59f5..ed749fed 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedArgument.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedArgument.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.*;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAssertion.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAssertion.java
index 2c38639d..b2ef6e48 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAssertion.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAssertion.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.Assertion;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAssertionArgument.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAssertionArgument.java
index 840c1f74..b36f2506 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAssertionArgument.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAssertionArgument.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.AssertionArgument;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAtom.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAtom.java
index 498991f8..c02f447b 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAtom.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedAtom.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.Atom;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedClassDeclaration.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedClassDeclaration.java
index 41b2ea62..a228137c 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedClassDeclaration.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedClassDeclaration.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.ClassDeclaration;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedConjunction.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedConjunction.java
index 88ff71ab..b126b1ce 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedConjunction.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedConjunction.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.Conjunction;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedConsequent.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedConsequent.java
index 46faa7da..8d6a92f8 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedConsequent.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedConsequent.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.Consequent;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedEnumDeclaration.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedEnumDeclaration.java
index 74dcf01b..229a8c0a 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedEnumDeclaration.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedEnumDeclaration.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.EnumDeclaration;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedLiteral.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedLiteral.java
index 4aa71b99..160e5dd8 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedLiteral.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedLiteral.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.Atom;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedParametricDefinition.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedParametricDefinition.java
index c2f18a60..d44b79ed 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedParametricDefinition.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedParametricDefinition.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.Parameter;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedPredicateDefinition.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedPredicateDefinition.java
index 7b95ecc1..2cf5fd89 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedPredicateDefinition.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedPredicateDefinition.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.PredicateDefinition;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedProblem.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedProblem.java
index 78ca95c7..e5aa0043 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedProblem.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedProblem.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import org.eclipse.emf.ecore.resource.Resource.Diagnostic;
diff --git a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedRuleDefinition.java b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedRuleDefinition.java
index a4cf2eaf..326d8ec3 100644
--- a/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedRuleDefinition.java
+++ b/subprojects/language/src/testFixtures/java/tools/refinery/language/model/tests/utils/WrappedRuleDefinition.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.language.model.tests.utils;
 
 import tools.refinery.language.model.problem.RuleDefinition;
diff --git a/subprojects/store-query-viatra/NOTICE.md b/subprojects/store-query-viatra/NOTICE.md
new file mode 100644
index 00000000..7c21726a
--- /dev/null
+++ b/subprojects/store-query-viatra/NOTICE.md
@@ -0,0 +1,87 @@
+<!--
+  Copyright (c) 2018-2019, Zoltan Ujhelyi, IncQuery Labs Ltd.
+  Copyright (c) 2023 The Refinery Authors <https://refinery.tools/>
+
+  SPDX-License-Identifier: EPL-2.0
+-->
+
+This module contains source code from the [Eclipse VIATRA project](https://projects.eclipse.org/projects/modeling.viatra), which is available under the terms of the [Eclipse Public License v 2.0](http://www.eclipse.org/legal/epl-v20.html).
+
+We reproduce the [accompanying notices](https://github.com/viatra/org.eclipse.viatra/blob/d422bcc626a99c4640c0d13931f393ccea0d2326/NOTICE.md) in full below:
+
+# Notices for Eclipse VIATRA
+
+This content is produced and maintained by the Eclipse VIATRA project.
+
+* Project home: https://projects.eclipse.org/projects/modeling.viatra
+
+## Trademarks
+
+Eclipse VIATRA, and VIATRA are trademarks of the Eclipse Foundation.
+
+## Copyright
+
+All content is the property of the respective authors or their employers. For
+more information regarding authorship of content, please consult the listed
+source code repository logs.
+
+## Declared Project Licenses
+
+This program and the accompanying materials are made available under the terms
+of the Eclipse Public License v. 2.0 which is available at
+http://www.eclipse.org/legal/epl-v20.html.
+
+SPDX-License-Identifier: EPL-2.0
+
+## Source Code
+
+The project maintains the following source code repositories:
+
+* http://git.eclipse.org/c/viatra/org.eclipse.viatra.git
+* http://git.eclipse.org/c/viatra/org.eclipse.viatra.modelobfuscator.git
+* http://git.eclipse.org/c/viatra/org.eclipse.viatra.examples.git
+* http://git.eclipse.org/c/viatra/org.eclipse.viatra2.vpm.git
+
+## Third-party Content
+
+This project leverages the following third party content.
+
+ANTLR Runtime only: (3.2)
+
+* License: New BSD license
+
+Apache Commons Language Library (2.1)
+
+* License: Apache License, 2.0
+
+Google Guice / Inject Core API (3.0.0)
+
+* License: Apache License, 2.0
+
+Google Guice / Inject Core API (3.0.0)
+
+* License: Apache License 2.0
+
+Guava (10.0.1)
+
+* License: Apache License, 2.0
+
+Guice (2.0)
+
+* License: Apache License, 2.0
+
+guice-multibindings (3.0.0)
+
+* License: Apache License, 2.0
+
+log4j (1.2.15)
+
+* License: Apache License 2.0
+
+LPG Java Runtime (lpgjavaruntime.jar) (1.1)
+
+* License: Eclipse Public License
+
+mockito (1.9.5)
+
+* License: Apache License, 2.0, New BSD license, MIT license
diff --git a/subprojects/store-query-viatra/build.gradle b/subprojects/store-query-viatra/build.gradle
deleted file mode 100644
index 13a7544f..00000000
--- a/subprojects/store-query-viatra/build.gradle
+++ /dev/null
@@ -1,16 +0,0 @@
-plugins {
-        id 'refinery-java-library'
-}
-
-configurations.testRuntimeClasspath {
-        // VIATRA requires log4j 1.x, but we use log4j-over-slf4j instead
-        exclude group: 'log4j', module: 'log4j'
-}
-
-dependencies {
-        implementation libs.ecore
-        api libs.viatra
-        api project(':refinery-store-query')
-        testImplementation libs.slf4j.simple
-        testImplementation libs.slf4j.log4j
-}
diff --git a/subprojects/store-query-viatra/build.gradle.kts b/subprojects/store-query-viatra/build.gradle.kts
new file mode 100644
index 00000000..e3a22145
--- /dev/null
+++ b/subprojects/store-query-viatra/build.gradle.kts
@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+plugins {
+        id("tools.refinery.gradle.java-library")
+}
+
+dependencies {
+        implementation(libs.ecore)
+        api(libs.viatra)
+        api(project(":refinery-store-query"))
+}
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQuery.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQuery.java
deleted file mode 100644
index 677e3c7d..00000000
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQuery.java
+++ /dev/null
@@ -1,21 +0,0 @@
-package tools.refinery.store.query.viatra;
-
-import tools.refinery.store.adapter.ModelAdapterBuilderFactory;
-import tools.refinery.store.model.ModelStoreBuilder;
-import tools.refinery.store.query.ModelQuery;
-import tools.refinery.store.query.viatra.internal.ViatraModelQueryBuilderImpl;
-
-public final class ViatraModelQuery extends ModelAdapterBuilderFactory<ViatraModelQueryAdapter,
-                ViatraModelQueryStoreAdapter, ViatraModelQueryBuilder> {
-        public static final ViatraModelQuery ADAPTER = new ViatraModelQuery();
-
-        private ViatraModelQuery() {
-                super(ViatraModelQueryAdapter.class, ViatraModelQueryStoreAdapter.class, ViatraModelQueryBuilder.class);
-                extendsAdapter(ModelQuery.ADAPTER);
-        }
-
-        @Override
-        public ViatraModelQueryBuilder createBuilder(ModelStoreBuilder storeBuilder) {
-                return new ViatraModelQueryBuilderImpl(storeBuilder);
-        }
-}
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryAdapter.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryAdapter.java
index 7e21476b..12c93f62 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryAdapter.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryAdapter.java
@@ -1,8 +1,18 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra;
 
 import tools.refinery.store.query.ModelQueryAdapter;
+import tools.refinery.store.query.viatra.internal.ViatraModelQueryBuilderImpl;
 
 public interface ViatraModelQueryAdapter extends ModelQueryAdapter {
         @Override
         ViatraModelQueryStoreAdapter getStoreAdapter();
+
+        static ViatraModelQueryBuilder builder() {
+                return new ViatraModelQueryBuilderImpl();
+        }
 }
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryBuilder.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryBuilder.java
index 7ae86f9f..931a07aa 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryBuilder.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryBuilder.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra;
 
 import org.eclipse.viatra.query.runtime.api.ViatraQueryEngineOptions;
@@ -45,5 +50,5 @@ public interface ViatraModelQueryBuilder extends ModelQueryBuilder {
         ViatraModelQueryBuilder hint(Dnf dnf, QueryEvaluationHint queryEvaluationHint);
 
         @Override
-        ViatraModelQueryStoreAdapter createStoreAdapter(ModelStore store);
+        ViatraModelQueryStoreAdapter build(ModelStore store);
 }
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryStoreAdapter.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryStoreAdapter.java
index 1ee02f12..da6d7bd5 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryStoreAdapter.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryStoreAdapter.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra;
 
 import org.eclipse.viatra.query.runtime.api.ViatraQueryEngineOptions;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/RelationalScope.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/RelationalScope.java
index 8328e759..d1a65a89 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/RelationalScope.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/RelationalScope.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal;
 
 import org.apache.log4j.Logger;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryAdapterImpl.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryAdapterImpl.java
index 8be30fee..7103a561 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryAdapterImpl.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryAdapterImpl.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal;
 
 import org.eclipse.viatra.query.runtime.api.AdvancedViatraQueryEngine;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryBuilderImpl.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryBuilderImpl.java
index bfabf26e..ce2467b4 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryBuilderImpl.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryBuilderImpl.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal;
 
 import org.eclipse.viatra.query.runtime.api.IQuerySpecification;
@@ -20,7 +25,8 @@ import tools.refinery.store.query.viatra.internal.pquery.Dnf2PQuery;
 import java.util.*;
 import java.util.function.Function;
 
-public class ViatraModelQueryBuilderImpl extends AbstractModelAdapterBuilder implements ViatraModelQueryBuilder {
+public class ViatraModelQueryBuilderImpl extends AbstractModelAdapterBuilder<ViatraModelQueryStoreAdapterImpl>
+                implements ViatraModelQueryBuilder {
         private ViatraQueryEngineOptions.Builder engineOptionsBuilder;
         private QueryEvaluationHint defaultHint = new QueryEvaluationHint(Map.of(
                         // Use a cost function that ignores the initial (empty) model but allows higher arity input keys.
@@ -30,8 +36,7 @@ public class ViatraModelQueryBuilderImpl extends AbstractModelAdapterBuilder imp
         private final Set<AnyQuery> vacuousQueries = new LinkedHashSet<>();
         private final Map<AnyQuery, IQuerySpecification<RawPatternMatcher>> querySpecifications = new LinkedHashMap<>();
 
-        public ViatraModelQueryBuilderImpl(ModelStoreBuilder storeBuilder) {
-                super(storeBuilder);
+        public ViatraModelQueryBuilderImpl() {
                 engineOptionsBuilder = new ViatraQueryEngineOptions.Builder()
                                 .withDefaultBackend(ReteBackendFactory.INSTANCE)
                                 .withDefaultCachingBackend(ReteBackendFactory.INSTANCE)
@@ -40,36 +45,42 @@ public class ViatraModelQueryBuilderImpl extends AbstractModelAdapterBuilder imp
 
         @Override
         public ViatraModelQueryBuilder engineOptions(ViatraQueryEngineOptions engineOptions) {
+                checkNotConfigured();
                 engineOptionsBuilder = new ViatraQueryEngineOptions.Builder(engineOptions);
                 return this;
         }
 
         @Override
         public ViatraModelQueryBuilder defaultHint(QueryEvaluationHint queryEvaluationHint) {
+                checkNotConfigured();
                 defaultHint = defaultHint.overrideBy(queryEvaluationHint);
                 return this;
         }
 
         @Override
         public ViatraModelQueryBuilder backend(IQueryBackendFactory queryBackendFactory) {
+                checkNotConfigured();
                 engineOptionsBuilder.withDefaultBackend(queryBackendFactory);
                 return this;
         }
 
         @Override
         public ViatraModelQueryBuilder cachingBackend(IQueryBackendFactory queryBackendFactory) {
+                checkNotConfigured();
                 engineOptionsBuilder.withDefaultCachingBackend(queryBackendFactory);
                 return this;
         }
 
         @Override
         public ViatraModelQueryBuilder searchBackend(IQueryBackendFactory queryBackendFactory) {
+                checkNotConfigured();
                 engineOptionsBuilder.withDefaultSearchBackend(queryBackendFactory);
                 return this;
         }
 
         @Override
         public ViatraModelQueryBuilder query(AnyQuery query) {
+                checkNotConfigured();
                 if (querySpecifications.containsKey(query) || vacuousQueries.contains(query)) {
                         // Ignore duplicate queries.
                         return this;
@@ -98,21 +109,27 @@ public class ViatraModelQueryBuilderImpl extends AbstractModelAdapterBuilder imp
 
         @Override
         public ViatraModelQueryBuilder computeHint(Function<Dnf, QueryEvaluationHint> computeHint) {
+                checkNotConfigured();
                 dnf2PQuery.setComputeHint(computeHint);
                 return this;
         }
 
         @Override
         public ViatraModelQueryBuilder hint(Dnf dnf, QueryEvaluationHint queryEvaluationHint) {
+                checkNotConfigured();
                 dnf2PQuery.hint(dnf, queryEvaluationHint);
                 return this;
         }
 
         @Override
-        public ViatraModelQueryStoreAdapterImpl createStoreAdapter(ModelStore store) {
-                validateSymbols(store);
+        public void doConfigure(ModelStoreBuilder storeBuilder) {
                 dnf2PQuery.assertNoUnusedHints();
-                return new ViatraModelQueryStoreAdapterImpl(store, buildEngineOptions(), dnf2PQuery.getRelationViews(),
+        }
+
+        @Override
+        public ViatraModelQueryStoreAdapterImpl doBuild(ModelStore store) {
+                validateSymbols(store);
+                return new ViatraModelQueryStoreAdapterImpl(store, buildEngineOptions(), dnf2PQuery.getSymbolViews(),
                                 Collections.unmodifiableMap(querySpecifications), Collections.unmodifiableSet(vacuousQueries));
         }
 
@@ -135,11 +152,11 @@ public class ViatraModelQueryBuilderImpl extends AbstractModelAdapterBuilder imp
 
         private void validateSymbols(ModelStore store) {
                 var symbols = store.getSymbols();
-                for (var relationView : dnf2PQuery.getRelationViews().keySet()) {
-                        var symbol = relationView.getSymbol();
+                for (var symbolView : dnf2PQuery.getSymbolViews().keySet()) {
+                        var symbol = symbolView.getSymbol();
                         if (!symbols.contains(symbol)) {
-                                throw new IllegalArgumentException("Cannot query relation view %s: symbol %s is not in the model"
-                                                .formatted(relationView, symbol));
+                                throw new IllegalArgumentException("Cannot query view %s: symbol %s is not in the model"
+                                                .formatted(symbolView, symbol));
                         }
                 }
         }
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryStoreAdapterImpl.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryStoreAdapterImpl.java
index 04c48c43..11a3c7fd 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryStoreAdapterImpl.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryStoreAdapterImpl.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal;
 
 import org.eclipse.viatra.query.runtime.api.IQuerySpecification;
@@ -8,20 +13,20 @@ import tools.refinery.store.model.ModelStore;
 import tools.refinery.store.query.dnf.AnyQuery;
 import tools.refinery.store.query.viatra.ViatraModelQueryStoreAdapter;
 import tools.refinery.store.query.viatra.internal.matcher.RawPatternMatcher;
-import tools.refinery.store.query.view.AnyRelationView;
+import tools.refinery.store.query.view.AnySymbolView;
 
 import java.util.*;
 
 public class ViatraModelQueryStoreAdapterImpl implements ViatraModelQueryStoreAdapter {
         private final ModelStore store;
         private final ViatraQueryEngineOptions engineOptions;
-        private final Map<AnyRelationView, IInputKey> inputKeys;
+        private final Map<AnySymbolView, IInputKey> inputKeys;
         private final Map<AnyQuery, IQuerySpecification<RawPatternMatcher>> querySpecifications;
         private final Set<AnyQuery> vacuousQueries;
         private final Set<AnyQuery> allQueries;
 
         ViatraModelQueryStoreAdapterImpl(ModelStore store, ViatraQueryEngineOptions engineOptions,
-                                                                         Map<AnyRelationView, IInputKey> inputKeys,
+                                                                         Map<AnySymbolView, IInputKey> inputKeys,
                                                                          Map<AnyQuery, IQuerySpecification<RawPatternMatcher>> querySpecifications,
                                                                          Set<AnyQuery> vacuousQueries) {
                 this.store = store;
@@ -40,11 +45,11 @@ public class ViatraModelQueryStoreAdapterImpl implements ViatraModelQueryStoreAd
                 return store;
         }
 
-        public Collection<AnyRelationView> getRelationViews() {
+        public Collection<AnySymbolView> getSymbolViews() {
                 return inputKeys.keySet();
         }
 
-        public Map<AnyRelationView, IInputKey> getInputKeys() {
+        public Map<AnySymbolView, IInputKey> getInputKeys() {
                 return inputKeys;
         }
 
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/cardinality/UpperCardinalitySumAggregationOperator.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/cardinality/UpperCardinalitySumAggregationOperator.java
deleted file mode 100644
index e0bca9e0..00000000
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/cardinality/UpperCardinalitySumAggregationOperator.java
+++ /dev/null
@@ -1,97 +0,0 @@
-package tools.refinery.store.query.viatra.internal.cardinality;
-
-import org.eclipse.viatra.query.runtime.matchers.psystem.aggregations.BoundAggregator;
-import org.eclipse.viatra.query.runtime.matchers.psystem.aggregations.IMultisetAggregationOperator;
-import tools.refinery.store.representation.cardinality.FiniteUpperCardinality;
-import tools.refinery.store.representation.cardinality.UnboundedUpperCardinality;
-import tools.refinery.store.representation.cardinality.UpperCardinalities;
-import tools.refinery.store.representation.cardinality.UpperCardinality;
-
-import java.util.stream.Stream;
-
-public class UpperCardinalitySumAggregationOperator implements IMultisetAggregationOperator<UpperCardinality,
-                UpperCardinalitySumAggregationOperator.Accumulator, UpperCardinality> {
-        public static final UpperCardinalitySumAggregationOperator INSTANCE = new UpperCardinalitySumAggregationOperator();
-
-        public static final BoundAggregator BOUND_AGGREGATOR = new BoundAggregator(INSTANCE, UpperCardinality.class,
-                        UpperCardinality.class);
-
-        private UpperCardinalitySumAggregationOperator() {
-                // Singleton constructor.
-        }
-
-        @Override
-        public String getName() {
-                return "sum<UpperCardinality>";
-        }
-
-        @Override
-        public String getShortDescription() {
-                return "%s computes the sum of finite or unbounded upper cardinalities".formatted(getName());
-        }
-
-        @Override
-        public Accumulator createNeutral() {
-                return new Accumulator();
-        }
-
-        @Override
-        public boolean isNeutral(Accumulator result) {
-                return result.sumFiniteUpperBounds == 0 && result.countUnbounded == 0;
-        }
-
-        @Override
-        public Accumulator update(Accumulator oldResult, UpperCardinality updateValue, boolean isInsertion) {
-                if (updateValue instanceof FiniteUpperCardinality finiteUpperCardinality) {
-                        int finiteUpperBound = finiteUpperCardinality.finiteUpperBound();
-                        if (isInsertion) {
-                                oldResult.sumFiniteUpperBounds += finiteUpperBound;
-                        } else {
-                                oldResult.sumFiniteUpperBounds -= finiteUpperBound;
-                        }
-                } else if (updateValue instanceof UnboundedUpperCardinality) {
-                        if (isInsertion) {
-                                oldResult.countUnbounded += 1;
-                        } else {
-                                oldResult.countUnbounded -= 1;
-                        }
-                } else {
-                        throw new IllegalArgumentException("Unknown UpperCardinality: " + updateValue);
-                }
-                return oldResult;
-        }
-
-        @Override
-        public UpperCardinality getAggregate(Accumulator result) {
-                return result.countUnbounded > 0 ? UpperCardinalities.UNBOUNDED :
-                                UpperCardinalities.valueOf(result.sumFiniteUpperBounds);
-        }
-
-        @Override
-        public UpperCardinality aggregateStream(Stream<UpperCardinality> stream) {
-                var result = stream.collect(this::createNeutral, (accumulator, value) -> update(accumulator, value, true),
-                                (left, right) -> new Accumulator(left.sumFiniteUpperBounds + right.sumFiniteUpperBounds,
-                                                left.countUnbounded + right.countUnbounded));
-                return getAggregate(result);
-        }
-
-        @Override
-        public Accumulator clone(Accumulator original) {
-                return new Accumulator(original.sumFiniteUpperBounds, original.countUnbounded);
-        }
-
-        public static class Accumulator {
-                private int sumFiniteUpperBounds;
-
-                private int countUnbounded;
-
-                private Accumulator(int sumFiniteUpperBounds, int countUnbounded) {
-                        this.sumFiniteUpperBounds = sumFiniteUpperBounds;
-                        this.countUnbounded = countUnbounded;
-                }
-
-                private Accumulator() {
-                        this(0, 0);
-                }
-        }
-}
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/DummyBaseIndexer.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/DummyBaseIndexer.java
index 2a24b67c..8cb199d2 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/DummyBaseIndexer.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/DummyBaseIndexer.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.context;
 
 import org.eclipse.viatra.query.runtime.api.scope.IBaseIndex;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalEngineContext.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalEngineContext.java
index 28bc69d0..7220f8ca 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalEngineContext.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalEngineContext.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.context;
 
 import org.eclipse.viatra.query.runtime.api.scope.IBaseIndex;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalQueryMetaContext.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalQueryMetaContext.java
index d2c6beb4..211eacb4 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalQueryMetaContext.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalQueryMetaContext.java
@@ -1,12 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.context;
 
 import org.eclipse.viatra.query.runtime.matchers.context.AbstractQueryMetaContext;
 import org.eclipse.viatra.query.runtime.matchers.context.IInputKey;
 import org.eclipse.viatra.query.runtime.matchers.context.InputKeyImplication;
 import org.eclipse.viatra.query.runtime.matchers.context.common.JavaTransitiveInstancesKey;
-import tools.refinery.store.query.term.DataSort;
-import tools.refinery.store.query.viatra.internal.pquery.RelationViewWrapper;
-import tools.refinery.store.query.view.AnyRelationView;
+import tools.refinery.store.query.viatra.internal.pquery.SymbolViewWrapper;
+import tools.refinery.store.query.view.AnySymbolView;
 
 import java.util.*;
 
@@ -14,9 +18,9 @@ import java.util.*;
  * The meta context information for String scopes.
  */
 public class RelationalQueryMetaContext extends AbstractQueryMetaContext {
-        private final Map<AnyRelationView, IInputKey> inputKeys;
+        private final Map<AnySymbolView, IInputKey> inputKeys;
 
-        RelationalQueryMetaContext(Map<AnyRelationView, IInputKey> inputKeys) {
+        RelationalQueryMetaContext(Map<AnySymbolView, IInputKey> inputKeys) {
                 this.inputKeys = inputKeys;
         }
 
@@ -42,29 +46,29 @@ public class RelationalQueryMetaContext extends AbstractQueryMetaContext {
                 if (implyingKey instanceof JavaTransitiveInstancesKey) {
                         return List.of();
                 }
-                var relationView = checkKey(implyingKey);
-                var relationViewImplications = relationView.getImpliedRelationViews();
+                var symbolView = checkKey(implyingKey);
+                var relationViewImplications = symbolView.getImpliedRelationViews();
                 var inputKeyImplications = new HashSet<InputKeyImplication>(relationViewImplications.size());
                 for (var relationViewImplication : relationViewImplications) {
-                        if (!relationView.equals(relationViewImplication.implyingRelationView())) {
+                        if (!symbolView.equals(relationViewImplication.implyingView())) {
                                 throw new IllegalArgumentException("Relation view %s returned unrelated implication %s".formatted(
-                                                relationView, relationViewImplication));
+                                                symbolView, relationViewImplication));
                         }
-                        var impliedInputKey = inputKeys.get(relationViewImplication.impliedRelationView());
+                        var impliedInputKey = inputKeys.get(relationViewImplication.impliedView());
                         // Ignore implications not relevant for any queries included in the model.
                         if (impliedInputKey != null) {
                                 inputKeyImplications.add(new InputKeyImplication(implyingKey, impliedInputKey,
                                                 relationViewImplication.impliedIndices()));
                         }
                 }
-                var sorts = relationView.getSorts();
-                int arity = relationView.arity();
+                var parameters = symbolView.getParameters();
+                int arity = symbolView.arity();
                 for (int i = 0; i < arity; i++) {
-                        var sort = sorts.get(i);
-                        if (sort instanceof DataSort<?> dataSort) {
-                                var javaTransitiveInstancesKey = new JavaTransitiveInstancesKey(dataSort.type());
-                                var javaImplication = new InputKeyImplication(implyingKey, javaTransitiveInstancesKey,
-                                                List.of(i));
+                        var parameter = parameters.get(i);
+                        var parameterType = parameter.tryGetType();
+                        if (parameterType.isPresent()) {
+                                var javaTransitiveInstancesKey = new JavaTransitiveInstancesKey(parameterType.get());
+                                var javaImplication = new InputKeyImplication(implyingKey, javaTransitiveInstancesKey, List.of(i));
                                 inputKeyImplications.add(javaImplication);
                         }
                 }
@@ -94,20 +98,20 @@ public class RelationalQueryMetaContext extends AbstractQueryMetaContext {
                 return flattened;
         }
 
-        private static void checkValidIndices(AnyRelationView relationView, Collection<Integer> indices) {
+        private static void checkValidIndices(AnySymbolView relationView, Collection<Integer> indices) {
                 indices.stream().filter(relationView::invalidIndex).findAny().ifPresent(i -> {
                         throw new IllegalArgumentException("Index %d is invalid for %s".formatted(i, relationView));
                 });
         }
 
-        public AnyRelationView checkKey(IInputKey key) {
-                if (!(key instanceof RelationViewWrapper wrapper)) {
+        public AnySymbolView checkKey(IInputKey key) {
+                if (!(key instanceof SymbolViewWrapper wrapper)) {
                         throw new IllegalArgumentException("The input key %s is not a valid input key".formatted(key));
                 }
-                var relationView = wrapper.getWrappedKey();
-                if (!inputKeys.containsKey(relationView)) {
+                var symbolView = wrapper.getWrappedKey();
+                if (!inputKeys.containsKey(symbolView)) {
                         throw new IllegalArgumentException("The input key %s is not present in the model".formatted(key));
                 }
-                return relationView;
+                return symbolView;
         }
 }
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalRuntimeContext.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalRuntimeContext.java
index 854817b1..0f2daca8 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalRuntimeContext.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalRuntimeContext.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.context;
 
 import org.eclipse.viatra.query.runtime.matchers.context.*;
@@ -8,9 +13,9 @@ import org.eclipse.viatra.query.runtime.matchers.tuple.Tuples;
 import org.eclipse.viatra.query.runtime.matchers.util.Accuracy;
 import tools.refinery.store.model.Model;
 import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
-import tools.refinery.store.query.viatra.internal.pquery.RelationViewWrapper;
+import tools.refinery.store.query.viatra.internal.pquery.SymbolViewWrapper;
 import tools.refinery.store.query.viatra.internal.update.ModelUpdateListener;
-import tools.refinery.store.query.view.AnyRelationView;
+import tools.refinery.store.query.view.AnySymbolView;
 
 import java.lang.reflect.InvocationTargetException;
 import java.util.Iterator;
@@ -54,9 +59,9 @@ public class RelationalRuntimeContext implements IQueryRuntimeContext {
 
         @Override
         public boolean isIndexed(IInputKey key, IndexingService service) {
-                if (key instanceof RelationViewWrapper wrapper) {
-                        var relationalKey = wrapper.getWrappedKey();
-                        return this.modelUpdateListener.containsRelationView(relationalKey);
+                if (key instanceof SymbolViewWrapper wrapper) {
+                        var symbolViewKey = wrapper.getWrappedKey();
+                        return this.modelUpdateListener.containsSymbolView(symbolViewKey);
                 } else {
                         return false;
                 }
@@ -69,13 +74,13 @@ public class RelationalRuntimeContext implements IQueryRuntimeContext {
                 }
         }
 
-        AnyRelationView checkKey(IInputKey key) {
-                if (key instanceof RelationViewWrapper wrappedKey) {
-                        var relationViewKey = wrappedKey.getWrappedKey();
-                        if (modelUpdateListener.containsRelationView(relationViewKey)) {
-                                return relationViewKey;
+        AnySymbolView checkKey(IInputKey key) {
+                if (key instanceof SymbolViewWrapper wrappedKey) {
+                        var symbolViewKey = wrappedKey.getWrappedKey();
+                        if (modelUpdateListener.containsSymbolView(symbolViewKey)) {
+                                return symbolViewKey;
                         } else {
-                                throw new IllegalStateException("Query is asking for non-indexed key %s".formatted(relationViewKey));
+                                throw new IllegalStateException("Query is asking for non-indexed key %s".formatted(symbolViewKey));
                         }
                 } else {
                         throw new IllegalStateException("Query is asking for non-relational key");
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/ExtendOperationExecutor.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/ExtendOperationExecutor.java
index 2d3dd5a7..37177cbf 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/ExtendOperationExecutor.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/ExtendOperationExecutor.java
@@ -1,5 +1,6 @@
 /*******************************************************************************
  * Copyright (c) 2010-2013, Zoltan Ujhelyi, Akos Horvath, Istvan Rath and Daniel Varro
+ * Copyright (c) 2023 The Refinery Authors <https://refinery.tools/>
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0 which is available at
  * http://www.eclipse.org/legal/epl-v20.html.
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/ExtendPositivePatternCall.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/ExtendPositivePatternCall.java
index aaaece80..9d48c785 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/ExtendPositivePatternCall.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/ExtendPositivePatternCall.java
@@ -1,5 +1,6 @@
 /*******************************************************************************
  * Copyright (c) 2010-2016, Grill Balázs, IncQueryLabs
+ * Copyright (c) 2023 The Refinery Authors <https://refinery.tools/>
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0 which is available at
  * http://www.eclipse.org/legal/epl-v20.html.
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/FlatCostFunction.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/FlatCostFunction.java
index 84cab142..cc906f22 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/FlatCostFunction.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/FlatCostFunction.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.localsearch;
 
 import org.eclipse.viatra.query.runtime.localsearch.planner.cost.IConstraintEvaluationContext;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/GenericTypeExtend.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/GenericTypeExtend.java
index 64653658..96ac4a72 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/GenericTypeExtend.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/GenericTypeExtend.java
@@ -1,5 +1,6 @@
 /*******************************************************************************
  * Copyright (c) 2010-2017, Zoltan Ujhelyi, IncQuery Labs Ltd.
+ * Copyright (c) 2023 The Refinery Authors <https://refinery.tools/>
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0 which is available at
  * http://www.eclipse.org/legal/epl-v20.html.
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/RelationalLocalSearchBackendFactory.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/RelationalLocalSearchBackendFactory.java
index 156eb313..0c77f587 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/RelationalLocalSearchBackendFactory.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/RelationalLocalSearchBackendFactory.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.localsearch;
 
 import org.eclipse.viatra.query.runtime.localsearch.matcher.integration.AbstractLocalSearchResultProvider;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/RelationalLocalSearchResultProvider.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/RelationalLocalSearchResultProvider.java
index be2a38ca..da37be14 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/RelationalLocalSearchResultProvider.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/RelationalLocalSearchResultProvider.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.localsearch;
 
 import org.eclipse.viatra.query.runtime.localsearch.matcher.integration.AbstractLocalSearchResultProvider;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/RelationalOperationCompiler.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/RelationalOperationCompiler.java
index b6832b39..f76ef486 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/RelationalOperationCompiler.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/localsearch/RelationalOperationCompiler.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.localsearch;
 
 import org.eclipse.viatra.query.runtime.localsearch.operations.generic.GenericTypeExtendSingleValue;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/FunctionalCursor.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/FunctionalCursor.java
index 4daa14a1..47efb2aa 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/FunctionalCursor.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/FunctionalCursor.java
@@ -1,17 +1,21 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.matcher;
 
-import org.eclipse.viatra.query.runtime.matchers.tuple.Tuple;
 import org.eclipse.viatra.query.runtime.rete.index.IterableIndexer;
 import tools.refinery.store.map.Cursor;
-import tools.refinery.store.tuple.TupleLike;
+import tools.refinery.store.tuple.Tuple;
 
 import java.util.Iterator;
 
-class FunctionalCursor<T> implements Cursor<TupleLike, T> {
+class FunctionalCursor<T> implements Cursor<Tuple, T> {
         private final IterableIndexer indexer;
-        private final Iterator<Tuple> iterator;
+        private final Iterator<org.eclipse.viatra.query.runtime.matchers.tuple.Tuple> iterator;
         private boolean terminated;
-        private TupleLike key;
+        private Tuple key;
         private T value;
 
         public FunctionalCursor(IterableIndexer indexer) {
@@ -20,7 +24,7 @@ class FunctionalCursor<T> implements Cursor<TupleLike, T> {
         }
 
         @Override
-        public TupleLike getKey() {
+        public Tuple getKey() {
                 return key;
         }
 
@@ -38,7 +42,7 @@ class FunctionalCursor<T> implements Cursor<TupleLike, T> {
         public boolean move() {
                 if (!terminated && iterator.hasNext()) {
                         var match = iterator.next();
-                        key = new ViatraTupleLike(match);
+                        key = MatcherUtils.toRefineryTuple(match);
                         value = MatcherUtils.getSingleValue(indexer.get(match));
                         return true;
                 }
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/FunctionalViatraMatcher.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/FunctionalViatraMatcher.java
index 6aa45af2..f018288b 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/FunctionalViatraMatcher.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/FunctionalViatraMatcher.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.matcher;
 
 import org.eclipse.viatra.query.runtime.matchers.backend.IQueryResultProvider;
@@ -11,7 +16,7 @@ import tools.refinery.store.query.ResultSet;
 import tools.refinery.store.query.dnf.FunctionalQuery;
 import tools.refinery.store.query.dnf.Query;
 import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
-import tools.refinery.store.tuple.TupleLike;
+import tools.refinery.store.tuple.Tuple;
 
 /**
  * Directly access the tuples inside a VIATRA pattern matcher.<p>
@@ -63,7 +68,7 @@ public class FunctionalViatraMatcher<T> implements ResultSet<T> {
         }
 
         @Override
-        public T get(TupleLike parameters) {
+        public T get(Tuple parameters) {
                 var tuple = MatcherUtils.toViatraTuple(parameters);
                 if (omitOutputIndexer == null) {
                         return MatcherUtils.getSingleValue(backend.getAllMatches(omitOutputMask, tuple).iterator());
@@ -73,7 +78,7 @@ public class FunctionalViatraMatcher<T> implements ResultSet<T> {
         }
 
         @Override
-        public Cursor<TupleLike, T> getAll() {
+        public Cursor<Tuple, T> getAll() {
                 if (omitOutputIndexer == null) {
                         var allMatches = backend.getAllMatches(emptyMask, Tuples.staticArityFlatTupleOf());
                         return new UnsafeFunctionalCursor<>(allMatches.iterator());
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/IndexerUtils.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/IndexerUtils.java
index 55eb8c44..15f00b2d 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/IndexerUtils.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/IndexerUtils.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.matcher;
 
 import org.eclipse.viatra.query.runtime.matchers.tuple.TupleMask;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/MatcherUtils.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/MatcherUtils.java
index 5d4be95d..1c784492 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/MatcherUtils.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/MatcherUtils.java
@@ -1,10 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.matcher;
 
 import org.eclipse.viatra.query.runtime.matchers.tuple.ITuple;
 import org.eclipse.viatra.query.runtime.matchers.tuple.Tuples;
 import org.jetbrains.annotations.Nullable;
-import tools.refinery.store.tuple.Tuple;
-import tools.refinery.store.tuple.TupleLike;
+import tools.refinery.store.tuple.*;
 
 import java.util.Iterator;
 
@@ -13,25 +17,80 @@ final class MatcherUtils {
                 throw new IllegalStateException("This is a static utility class and should not be instantiated directly");
         }
 
-        public static org.eclipse.viatra.query.runtime.matchers.tuple.Tuple toViatraTuple(TupleLike tuple) {
-                if (tuple instanceof ViatraTupleLike viatraTupleLike) {
-                        return viatraTupleLike.wrappedTuple().toImmutable();
+        public static org.eclipse.viatra.query.runtime.matchers.tuple.Tuple toViatraTuple(Tuple refineryTuple) {
+                if (refineryTuple instanceof Tuple0) {
+                        return Tuples.staticArityFlatTupleOf();
+                } else if (refineryTuple instanceof Tuple1) {
+                        return Tuples.staticArityFlatTupleOf(refineryTuple);
+                } else if (refineryTuple instanceof Tuple2 tuple2) {
+                        return Tuples.staticArityFlatTupleOf(Tuple.of(tuple2.value0()), Tuple.of(tuple2.value1()));
+                } else if (refineryTuple instanceof Tuple3 tuple3) {
+                        return Tuples.staticArityFlatTupleOf(Tuple.of(tuple3.value0()), Tuple.of(tuple3.value1()),
+                                        Tuple.of(tuple3.value2()));
+                } else if (refineryTuple instanceof Tuple4 tuple4) {
+                        return Tuples.staticArityFlatTupleOf(Tuple.of(tuple4.value0()), Tuple.of(tuple4.value1()),
+                                        Tuple.of(tuple4.value2()), Tuple.of(tuple4.value3()));
+                } else {
+                        int arity = refineryTuple.getSize();
+                        var values = new Object[arity];
+                        for (int i = 0; i < arity; i++) {
+                                values[i] = Tuple.of(refineryTuple.get(i));
+                        }
+                        return Tuples.flatTupleOf(values);
                 }
-                int size = tuple.getSize();
-                var array = new Object[size];
-                for (int i = 0; i < size; i++) {
-                        var value = tuple.get(i);
-                        array[i] = Tuple.of(value);
+        }
+
+        public static Tuple toRefineryTuple(ITuple viatraTuple) {
+                int arity = viatraTuple.getSize();
+                if (arity == 1) {
+                        return getWrapper(viatraTuple, 0);
                 }
-                return Tuples.flatTupleOf(array);
+                return prefixToRefineryTuple(viatraTuple, viatraTuple.getSize());
+        }
+
+        public static Tuple keyToRefineryTuple(ITuple viatraTuple) {
+                return prefixToRefineryTuple(viatraTuple, viatraTuple.getSize() - 1);
         }
 
+        private static Tuple prefixToRefineryTuple(ITuple viatraTuple, int targetArity) {
+                if (targetArity < 0) {
+                        throw new IllegalArgumentException("Requested negative prefix %d of %s"
+                                        .formatted(targetArity, viatraTuple));
+                }
+                return switch (targetArity) {
+                        case 0 -> Tuple.of();
+                        case 1 -> Tuple.of(unwrap(viatraTuple, 0));
+                        case 2 -> Tuple.of(unwrap(viatraTuple, 0), unwrap(viatraTuple, 1));
+                        case 3 -> Tuple.of(unwrap(viatraTuple, 0), unwrap(viatraTuple, 1), unwrap(viatraTuple, 2));
+                        case 4 -> Tuple.of(unwrap(viatraTuple, 0), unwrap(viatraTuple, 1), unwrap(viatraTuple, 2),
+                                        unwrap(viatraTuple, 3));
+                        default -> {
+                                var entries = new int[targetArity];
+                                for (int i = 0; i < targetArity; i++) {
+                                        entries[i] = unwrap(viatraTuple, i);
+                                }
+                                yield Tuple.of(entries);
+                        }
+                };
+        }
+
+        private static Tuple1 getWrapper(ITuple viatraTuple, int index) {
+                if (!((viatraTuple.get(index)) instanceof Tuple1 wrappedObjectId)) {
+                        throw new IllegalArgumentException("Element %d of tuple %s is not an object id"
+                                        .formatted(index, viatraTuple));
+                }
+                return wrappedObjectId;
+        }
+
+        private static int unwrap(ITuple viatraTuple, int index) {
+                return getWrapper(viatraTuple, index).value0();
+        }
 
-        public static <T> T getSingleValue(@Nullable Iterable<? extends ITuple> tuples) {
-                if (tuples == null) {
+        public static <T> T getSingleValue(@Nullable Iterable<? extends ITuple> viatraTuples) {
+                if (viatraTuples == null) {
                         return null;
                 }
-                return getSingleValue(tuples.iterator());
+                return getSingleValue(viatraTuples.iterator());
         }
 
         public static <T> T getSingleValue(Iterator<? extends ITuple> iterator) {
@@ -42,7 +101,7 @@ final class MatcherUtils {
                 @SuppressWarnings("unchecked")
                 var result = (T) match.get(match.getSize() - 1);
                 if (iterator.hasNext()) {
-                        var input = new OmitOutputViatraTupleLike(match);
+                        var input = keyToRefineryTuple(match);
                         throw new IllegalStateException("Query is not functional for input tuple: " + input);
                 }
                 return result;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/OmitOutputViatraTupleLike.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/OmitOutputViatraTupleLike.java
deleted file mode 100644
index bd9301ba..00000000
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/OmitOutputViatraTupleLike.java
+++ /dev/null
@@ -1,23 +0,0 @@
-package tools.refinery.store.query.viatra.internal.matcher;
-
-import org.eclipse.viatra.query.runtime.matchers.tuple.ITuple;
-import tools.refinery.store.tuple.Tuple1;
-import tools.refinery.store.tuple.TupleLike;
-
-record OmitOutputViatraTupleLike(ITuple wrappedTuple) implements TupleLike {
-        @Override
-        public int getSize() {
-                return wrappedTuple.getSize() - 1;
-        }
-
-        @Override
-        public int get(int element) {
-                var wrappedValue = (Tuple1) wrappedTuple.get(element);
-                return wrappedValue.value0();
-        }
-
-        @Override
-        public String toString() {
-                return TupleLike.toString(this);
-        }
-}
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/RawPatternMatcher.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/RawPatternMatcher.java
index b3d05967..5b82c4b7 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/RawPatternMatcher.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/RawPatternMatcher.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.matcher;
 
 import org.eclipse.viatra.query.runtime.api.GenericPatternMatcher;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/RelationalCursor.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/RelationalCursor.java
index c2dcc565..1dc8f5db 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/RelationalCursor.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/RelationalCursor.java
@@ -1,22 +1,27 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.matcher;
 
 import org.eclipse.viatra.query.runtime.matchers.tuple.ITuple;
 import tools.refinery.store.map.Cursor;
-import tools.refinery.store.tuple.TupleLike;
+import tools.refinery.store.tuple.Tuple;
 
 import java.util.Iterator;
 
-class RelationalCursor implements Cursor<TupleLike, Boolean> {
+class RelationalCursor implements Cursor<Tuple, Boolean> {
     private final Iterator<? extends ITuple> tuplesIterator;
     private boolean terminated;
-    private TupleLike key;
+    private Tuple key;
 
     public RelationalCursor(Iterator<? extends ITuple> tuplesIterator) {
         this.tuplesIterator = tuplesIterator;
     }
 
     @Override
-    public TupleLike getKey() {
+    public Tuple getKey() {
         return key;
     }
 
@@ -33,7 +38,7 @@ class RelationalCursor implements Cursor<TupleLike, Boolean> {
     @Override
     public boolean move() {
         if (!terminated && tuplesIterator.hasNext()) {
-            key = new ViatraTupleLike(tuplesIterator.next());
+            key = MatcherUtils.toRefineryTuple(tuplesIterator.next());
             return true;
         }
         terminated = true;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/RelationalViatraMatcher.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/RelationalViatraMatcher.java
index b9bc3f1e..d1476920 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/RelationalViatraMatcher.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/RelationalViatraMatcher.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.matcher;
 
 import org.eclipse.viatra.query.runtime.matchers.backend.IQueryResultProvider;
@@ -12,7 +17,7 @@ import tools.refinery.store.query.ResultSet;
 import tools.refinery.store.query.dnf.Query;
 import tools.refinery.store.query.dnf.RelationalQuery;
 import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
-import tools.refinery.store.tuple.TupleLike;
+import tools.refinery.store.tuple.Tuple;
 
 /**
  * Directly access the tuples inside a VIATRA pattern matcher.<p>
@@ -58,7 +63,7 @@ public class RelationalViatraMatcher implements ResultSet<Boolean> {
         }
 
         @Override
-        public Boolean get(TupleLike parameters) {
+        public Boolean get(Tuple parameters) {
                 var tuple = MatcherUtils.toViatraTuple(parameters);
                 if (emptyMaskIndexer == null) {
                         return backend.hasMatch(identityMask, tuple);
@@ -68,7 +73,7 @@ public class RelationalViatraMatcher implements ResultSet<Boolean> {
         }
 
         @Override
-        public Cursor<TupleLike, Boolean> getAll() {
+        public Cursor<Tuple, Boolean> getAll() {
                 if (emptyMaskIndexer == null) {
                         var allMatches = backend.getAllMatches(emptyMask, Tuples.staticArityFlatTupleOf());
                         return new RelationalCursor(allMatches.iterator());
@@ -85,5 +90,4 @@ public class RelationalViatraMatcher implements ResultSet<Boolean> {
                 var matches = emptyMaskIndexer.get(Tuples.staticArityFlatTupleOf());
                 return matches == null ? 0 : matches.size();
         }
-
 }
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/UnsafeFunctionalCursor.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/UnsafeFunctionalCursor.java
index 6c53fff1..4a41d724 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/UnsafeFunctionalCursor.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/UnsafeFunctionalCursor.java
@@ -1,8 +1,13 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.matcher;
 
 import org.eclipse.viatra.query.runtime.matchers.tuple.ITuple;
 import tools.refinery.store.map.Cursor;
-import tools.refinery.store.tuple.TupleLike;
+import tools.refinery.store.tuple.Tuple;
 
 import java.util.Iterator;
 
@@ -11,10 +16,10 @@ import java.util.Iterator;
  * functional dependency of the output on the inputs is obeyed.
  * @param <T> The output type.
  */
-class UnsafeFunctionalCursor<T> implements Cursor<TupleLike, T> {
+class UnsafeFunctionalCursor<T> implements Cursor<Tuple, T> {
         private final Iterator<? extends ITuple> tuplesIterator;
         private boolean terminated;
-        private TupleLike key;
+        private Tuple key;
         private T value;
 
         public UnsafeFunctionalCursor(Iterator<? extends ITuple> tuplesIterator) {
@@ -22,7 +27,7 @@ class UnsafeFunctionalCursor<T> implements Cursor<TupleLike, T> {
         }
 
         @Override
-        public TupleLike getKey() {
+        public Tuple getKey() {
                 return key;
         }
 
@@ -40,7 +45,7 @@ class UnsafeFunctionalCursor<T> implements Cursor<TupleLike, T> {
         public boolean move() {
                 if (!terminated && tuplesIterator.hasNext()) {
                         var match = tuplesIterator.next();
-                        key = new OmitOutputViatraTupleLike(match);
+                        key = MatcherUtils.keyToRefineryTuple(match);
                         @SuppressWarnings("unchecked")
                         var typedValue = (T) match.get(match.getSize() - 1);
                         value = typedValue;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/ViatraTupleLike.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/ViatraTupleLike.java
deleted file mode 100644
index 76a3e40b..00000000
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/matcher/ViatraTupleLike.java
+++ /dev/null
@@ -1,23 +0,0 @@
-package tools.refinery.store.query.viatra.internal.matcher;
-
-import org.eclipse.viatra.query.runtime.matchers.tuple.ITuple;
-import tools.refinery.store.tuple.Tuple1;
-import tools.refinery.store.tuple.TupleLike;
-
-record ViatraTupleLike(ITuple wrappedTuple) implements TupleLike {
-        @Override
-        public int getSize() {
-                return wrappedTuple.getSize();
-        }
-
-        @Override
-        public int get(int element) {
-                var wrappedValue = (Tuple1) wrappedTuple.get(element);
-                return wrappedValue.value0();
-        }
-
-        @Override
-        public String toString() {
-                return TupleLike.toString(this);
-        }
-}
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/AssumptionEvaluator.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/AssumptionEvaluator.java
index a80b0f90..cf127291 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/AssumptionEvaluator.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/AssumptionEvaluator.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.pquery;
 
 import org.eclipse.viatra.query.runtime.matchers.psystem.IValueProvider;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/Dnf2PQuery.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/Dnf2PQuery.java
index 7afeb977..5b0ea61d 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/Dnf2PQuery.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/Dnf2PQuery.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.pquery;
 
 import org.eclipse.viatra.query.runtime.matchers.backend.IQueryBackendFactory;
@@ -14,17 +19,19 @@ import org.eclipse.viatra.query.runtime.matchers.psystem.basicenumerables.Consta
 import org.eclipse.viatra.query.runtime.matchers.psystem.basicenumerables.PositivePatternCall;
 import org.eclipse.viatra.query.runtime.matchers.psystem.basicenumerables.TypeConstraint;
 import org.eclipse.viatra.query.runtime.matchers.psystem.queries.PParameter;
+import org.eclipse.viatra.query.runtime.matchers.psystem.queries.PParameterDirection;
 import org.eclipse.viatra.query.runtime.matchers.psystem.queries.PQuery;
 import org.eclipse.viatra.query.runtime.matchers.tuple.Tuple;
 import org.eclipse.viatra.query.runtime.matchers.tuple.Tuples;
 import tools.refinery.store.query.dnf.Dnf;
 import tools.refinery.store.query.dnf.DnfClause;
+import tools.refinery.store.query.dnf.SymbolicParameter;
 import tools.refinery.store.query.literal.*;
 import tools.refinery.store.query.term.ConstantTerm;
 import tools.refinery.store.query.term.StatefulAggregator;
 import tools.refinery.store.query.term.StatelessAggregator;
 import tools.refinery.store.query.term.Variable;
-import tools.refinery.store.query.view.AnyRelationView;
+import tools.refinery.store.query.view.AnySymbolView;
 import tools.refinery.store.util.CycleDetectingMapper;
 
 import java.util.*;
@@ -48,8 +55,8 @@ public class Dnf2PQuery {
                 return mapper.map(dnfQuery);
         }
 
-        public Map<AnyRelationView, IInputKey> getRelationViews() {
-                return wrapperFactory.getRelationViews();
+        public Map<AnySymbolView, IInputKey> getSymbolViews() {
+                return wrapperFactory.getSymbolViews();
         }
 
         public void hint(Dnf dnf, QueryEvaluationHint hint) {
@@ -77,15 +84,19 @@ public class Dnf2PQuery {
                 var pQuery = new RawPQuery(dnfQuery.getUniqueName());
                 pQuery.setEvaluationHints(consumeHint(dnfQuery));
 
-                Map<Variable, PParameter> parameters = new HashMap<>();
-                for (Variable variable : dnfQuery.getParameters()) {
-                        parameters.put(variable, new PParameter(variable.getUniqueName()));
-                }
-
+                Map<SymbolicParameter, PParameter> parameters = new HashMap<>();
                 List<PParameter> parameterList = new ArrayList<>();
-                for (var param : dnfQuery.getParameters()) {
-                        parameterList.add(parameters.get(param));
+                for (var parameter : dnfQuery.getSymbolicParameters()) {
+                        var direction = switch (parameter.getDirection()) {
+                                case OUT -> parameter.isUnifiable() ? PParameterDirection.INOUT : PParameterDirection.OUT;
+                                case IN -> throw new IllegalArgumentException("Query %s with input parameter %s is not supported"
+                                                .formatted(dnfQuery, parameter.getVariable()));
+                        };
+                        var pParameter = new PParameter(parameter.getVariable().getUniqueName(), null, null, direction);
+                        parameters.put(parameter, pParameter);
+                        parameterList.add(pParameter);
                 }
+
                 pQuery.setParameters(parameterList);
 
                 for (var functionalDependency : dnfQuery.getFunctionalDependencies()) {
@@ -105,15 +116,15 @@ public class Dnf2PQuery {
                 synchronized (P_CONSTRAINT_LOCK) {
                         for (DnfClause clause : dnfQuery.getClauses()) {
                                 PBody body = new PBody(pQuery);
-                                List<ExportedParameter> symbolicParameters = new ArrayList<>();
-                                for (var param : dnfQuery.getParameters()) {
-                                        PVariable pVar = body.getOrCreateVariableByName(param.getUniqueName());
-                                        symbolicParameters.add(new ExportedParameter(body, pVar, parameters.get(param)));
+                                List<ExportedParameter> parameterExports = new ArrayList<>();
+                                for (var parameter : dnfQuery.getSymbolicParameters()) {
+                                        PVariable pVar = body.getOrCreateVariableByName(parameter.getVariable().getUniqueName());
+                                        parameterExports.add(new ExportedParameter(body, pVar, parameters.get(parameter)));
                                 }
-                                body.setSymbolicParameters(symbolicParameters);
+                                body.setSymbolicParameters(parameterExports);
                                 pQuery.addBody(body);
                                 for (Literal literal : clause.literals()) {
-                                        translateLiteral(literal, clause, body);
+                                        translateLiteral(literal, body);
                                 }
                         }
                 }
@@ -121,11 +132,11 @@ public class Dnf2PQuery {
                 return pQuery;
         }
 
-        private void translateLiteral(Literal literal, DnfClause clause, PBody body) {
+        private void translateLiteral(Literal literal, PBody body) {
                 if (literal instanceof EquivalenceLiteral equivalenceLiteral) {
                         translateEquivalenceLiteral(equivalenceLiteral, body);
                 } else if (literal instanceof CallLiteral callLiteral) {
-                        translateCallLiteral(callLiteral, clause, body);
+                        translateCallLiteral(callLiteral, body);
                 } else if (literal instanceof ConstantLiteral constantLiteral) {
                         translateConstantLiteral(constantLiteral, body);
                 } else if (literal instanceof AssignLiteral<?> assignLiteral) {
@@ -133,9 +144,9 @@ public class Dnf2PQuery {
                 } else if (literal instanceof AssumeLiteral assumeLiteral) {
                         translateAssumeLiteral(assumeLiteral, body);
                 } else if (literal instanceof CountLiteral countLiteral) {
-                        translateCountLiteral(countLiteral, clause, body);
+                        translateCountLiteral(countLiteral, body);
                 } else if (literal instanceof AggregationLiteral<?, ?> aggregationLiteral) {
-                        translateAggregationLiteral(aggregationLiteral, clause, body);
+                        translateAggregationLiteral(aggregationLiteral, body);
                 } else {
                         throw new IllegalArgumentException("Unknown literal: " + literal.toString());
                 }
@@ -151,7 +162,7 @@ public class Dnf2PQuery {
                 }
         }
 
-        private void translateCallLiteral(CallLiteral callLiteral, DnfClause clause, PBody body) {
+        private void translateCallLiteral(CallLiteral callLiteral, PBody body) {
                 var polarity = callLiteral.getPolarity();
                 switch (polarity) {
                 case POSITIVE -> {
@@ -160,8 +171,8 @@ public class Dnf2PQuery {
                         if (constraint instanceof Dnf dnf) {
                                 var pattern = translate(dnf);
                                 new PositivePatternCall(body, substitution, pattern);
-                        } else if (constraint instanceof AnyRelationView relationView) {
-                                var inputKey = wrapperFactory.getInputKey(relationView);
+                        } else if (constraint instanceof AnySymbolView symbolView) {
+                                var inputKey = wrapperFactory.getInputKey(symbolView);
                                 new TypeConstraint(body, substitution, inputKey);
                         } else {
                                 throw new IllegalArgumentException("Unknown Constraint: " + constraint);
@@ -173,15 +184,15 @@ public class Dnf2PQuery {
                         PQuery pattern;
                         if (constraint instanceof Dnf dnf) {
                                 pattern = translate(dnf);
-                        } else if (constraint instanceof AnyRelationView relationView) {
-                                pattern = wrapperFactory.wrapRelationViewIdentityArguments(relationView);
+                        } else if (constraint instanceof AnySymbolView symbolView) {
+                                pattern = wrapperFactory.wrapSymbolViewIdentityArguments(symbolView);
                         } else {
                                 throw new IllegalArgumentException("Unknown Constraint: " + constraint);
                         }
                         new BinaryTransitiveClosure(body, substitution, pattern);
                 }
                 case NEGATIVE -> {
-                        var wrappedCall = wrapperFactory.maybeWrapConstraint(callLiteral, clause);
+                        var wrappedCall = wrapperFactory.maybeWrapConstraint(callLiteral);
                         var substitution = translateSubstitution(wrappedCall.remappedArguments(), body);
                         var pattern = wrappedCall.pattern();
                         new NegativePatternCall(body, substitution, pattern);
@@ -221,15 +232,14 @@ public class Dnf2PQuery {
                 new ExpressionEvaluation(body, evaluator, null);
         }
 
-        private void translateCountLiteral(CountLiteral countLiteral, DnfClause clause, PBody body) {
-                var wrappedCall = wrapperFactory.maybeWrapConstraint(countLiteral, clause);
+        private void translateCountLiteral(CountLiteral countLiteral, PBody body) {
+                var wrappedCall = wrapperFactory.maybeWrapConstraint(countLiteral);
                 var substitution = translateSubstitution(wrappedCall.remappedArguments(), body);
                 var resultVariable = body.getOrCreateVariableByName(countLiteral.getResultVariable().getUniqueName());
                 new PatternMatchCounter(body, substitution, wrappedCall.pattern(), resultVariable);
         }
 
-        private <R, T> void translateAggregationLiteral(AggregationLiteral<R, T> aggregationLiteral, DnfClause clause,
-                                                                                                        PBody body) {
+        private <R, T> void translateAggregationLiteral(AggregationLiteral<R, T> aggregationLiteral, PBody body) {
                 var aggregator = aggregationLiteral.getAggregator();
                 IMultisetAggregationOperator<T, ?, R> aggregationOperator;
                 if (aggregator instanceof StatelessAggregator<R, T> statelessAggregator) {
@@ -239,7 +249,7 @@ public class Dnf2PQuery {
                 } else {
                         throw new IllegalArgumentException("Unknown aggregator: " + aggregator);
                 }
-                var wrappedCall = wrapperFactory.maybeWrapConstraint(aggregationLiteral, clause);
+                var wrappedCall = wrapperFactory.maybeWrapConstraint(aggregationLiteral);
                 var substitution = translateSubstitution(wrappedCall.remappedArguments(), body);
                 var inputVariable = body.getOrCreateVariableByName(aggregationLiteral.getInputVariable().getUniqueName());
                 var aggregatedColumn = substitution.invertIndex().get(inputVariable);
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/QueryWrapperFactory.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/QueryWrapperFactory.java
index 24ae5196..2b7280f2 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/QueryWrapperFactory.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/QueryWrapperFactory.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.pquery;
 
 import org.eclipse.viatra.query.runtime.matchers.context.IInputKey;
@@ -9,15 +14,16 @@ import org.eclipse.viatra.query.runtime.matchers.psystem.basicenumerables.TypeCo
 import org.eclipse.viatra.query.runtime.matchers.psystem.queries.PParameter;
 import org.eclipse.viatra.query.runtime.matchers.psystem.queries.PQuery;
 import org.eclipse.viatra.query.runtime.matchers.psystem.queries.PVisibility;
+import org.eclipse.viatra.query.runtime.matchers.tuple.Tuple;
 import org.eclipse.viatra.query.runtime.matchers.tuple.Tuples;
 import tools.refinery.store.query.Constraint;
 import tools.refinery.store.query.dnf.Dnf;
-import tools.refinery.store.query.dnf.DnfClause;
 import tools.refinery.store.query.dnf.DnfUtils;
 import tools.refinery.store.query.literal.AbstractCallLiteral;
+import tools.refinery.store.query.term.ParameterDirection;
 import tools.refinery.store.query.term.Variable;
-import tools.refinery.store.query.view.AnyRelationView;
-import tools.refinery.store.query.view.RelationView;
+import tools.refinery.store.query.view.AnySymbolView;
+import tools.refinery.store.query.view.SymbolView;
 import tools.refinery.store.util.CycleDetectingMapper;
 
 import java.util.*;
@@ -25,7 +31,7 @@ import java.util.function.ToIntFunction;
 
 class QueryWrapperFactory {
         private final Dnf2PQuery dnf2PQuery;
-        private final Map<AnyRelationView, RelationViewWrapper> view2WrapperMap = new LinkedHashMap<>();
+        private final Map<AnySymbolView, SymbolViewWrapper> view2WrapperMap = new LinkedHashMap<>();
         private final CycleDetectingMapper<RemappedConstraint, RawPQuery> wrapConstraint = new CycleDetectingMapper<>(
                         RemappedConstraint::toString, this::doWrapConstraint);
 
@@ -33,28 +39,24 @@ class QueryWrapperFactory {
                 this.dnf2PQuery = dnf2PQuery;
         }
 
-        public PQuery wrapRelationViewIdentityArguments(AnyRelationView relationView) {
-                var identity = new int[relationView.arity()];
+        public PQuery wrapSymbolViewIdentityArguments(AnySymbolView symbolView) {
+                var identity = new int[symbolView.arity()];
                 for (int i = 0; i < identity.length; i++) {
                         identity[i] = i;
                 }
-                return maybeWrapConstraint(relationView, identity);
+                return maybeWrapConstraint(symbolView, identity);
         }
-        public WrappedCall maybeWrapConstraint(AbstractCallLiteral callLiteral, DnfClause clause) {
+
+        public WrappedCall maybeWrapConstraint(AbstractCallLiteral callLiteral) {
                 var arguments = callLiteral.getArguments();
                 int arity = arguments.size();
                 var remappedParameters = new int[arity];
-                var boundVariables = clause.boundVariables();
                 var unboundVariableIndices = new HashMap<Variable, Integer>();
                 var appendVariable = new VariableAppender();
                 for (int i = 0; i < arity; i++) {
                         var variable = arguments.get(i);
-                        if (boundVariables.contains(variable)) {
-                                // Do not join bound variable to make sure that the embedded pattern stays as general as possible.
-                                remappedParameters[i] = appendVariable.applyAsInt(variable);
-                        } else {
-                                remappedParameters[i] = unboundVariableIndices.computeIfAbsent(variable, appendVariable::applyAsInt);
-                        }
+                        // Unify all variables to avoid VIATRA bugs, even if they're bound in the containing clause.
+                        remappedParameters[i] = unboundVariableIndices.computeIfAbsent(variable, appendVariable::applyAsInt);
                 }
                 var pattern = maybeWrapConstraint(callLiteral.getTarget(), remappedParameters);
                 return new WrappedCall(pattern, appendVariable.getRemappedArguments());
@@ -84,6 +86,8 @@ class QueryWrapperFactory {
                 var constraint = remappedConstraint.constraint();
                 var remappedParameters = remappedConstraint.remappedParameters();
 
+                checkNoInputParameters(constraint);
+
                 var embeddedPQuery = new RawPQuery(DnfUtils.generateUniqueName(constraint.name()), PVisibility.EMBEDDED);
                 var body = new PBody(embeddedPQuery);
                 int arity = Arrays.stream(remappedParameters).max().orElse(-1) + 1;
@@ -107,24 +111,36 @@ class QueryWrapperFactory {
                 }
                 var argumentTuple = Tuples.flatTupleOf(arguments);
 
-                if (constraint instanceof RelationView<?> relationView) {
-                        new TypeConstraint(body, argumentTuple, getInputKey(relationView));
+                addPositiveConstraint(constraint, body, argumentTuple);
+                embeddedPQuery.addBody(body);
+                return embeddedPQuery;
+        }
+
+        private static void checkNoInputParameters(Constraint constraint) {
+                for (var constraintParameter : constraint.getParameters()) {
+                        if (constraintParameter.getDirection() == ParameterDirection.IN) {
+                                throw new IllegalArgumentException("Input parameter %s of %s is not supported"
+                                                .formatted(constraintParameter, constraint));
+                        }
+                }
+        }
+
+        private void addPositiveConstraint(Constraint constraint, PBody body, Tuple argumentTuple) {
+                if (constraint instanceof SymbolView<?> view) {
+                        new TypeConstraint(body, argumentTuple, getInputKey(view));
                 } else if (constraint instanceof Dnf dnf) {
                         var calledPQuery = dnf2PQuery.translate(dnf);
                         new PositivePatternCall(body, argumentTuple, calledPQuery);
                 } else {
                         throw new IllegalArgumentException("Unknown Constraint: " + constraint);
                 }
-
-                embeddedPQuery.addBody(body);
-                return embeddedPQuery;
         }
 
-        public IInputKey getInputKey(AnyRelationView relationView) {
-                return view2WrapperMap.computeIfAbsent(relationView, RelationViewWrapper::new);
+        public IInputKey getInputKey(AnySymbolView symbolView) {
+                return view2WrapperMap.computeIfAbsent(symbolView, SymbolViewWrapper::new);
         }
 
-        public Map<AnyRelationView, IInputKey> getRelationViews() {
+        public Map<AnySymbolView, IInputKey> getSymbolViews() {
                 return Collections.unmodifiableMap(view2WrapperMap);
         }
 
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/RawPQuery.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/RawPQuery.java
index aad4ba3c..255738c5 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/RawPQuery.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/RawPQuery.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.pquery;
 
 import org.eclipse.viatra.query.runtime.api.GenericQuerySpecification;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/StatefulMultisetAggregator.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/StatefulMultisetAggregator.java
index 2798a252..461416f7 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/StatefulMultisetAggregator.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/StatefulMultisetAggregator.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.pquery;
 
 import org.eclipse.viatra.query.runtime.matchers.psystem.aggregations.IMultisetAggregationOperator;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/StatelessMultisetAggregator.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/StatelessMultisetAggregator.java
index 7cc71ee9..49175d75 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/StatelessMultisetAggregator.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/StatelessMultisetAggregator.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.pquery;
 
 import org.eclipse.viatra.query.runtime.matchers.psystem.aggregations.IMultisetAggregationOperator;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/RelationViewWrapper.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/SymbolViewWrapper.java
index 48bf558d..a777613e 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/RelationViewWrapper.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/SymbolViewWrapper.java
@@ -1,10 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.pquery;
 
 import org.eclipse.viatra.query.runtime.matchers.context.common.BaseInputKeyWrapper;
-import tools.refinery.store.query.view.AnyRelationView;
+import tools.refinery.store.query.view.AnySymbolView;
 
-public class RelationViewWrapper extends BaseInputKeyWrapper<AnyRelationView> {
-        public RelationViewWrapper(AnyRelationView wrappedKey) {
+public class SymbolViewWrapper extends BaseInputKeyWrapper<AnySymbolView> {
+        public SymbolViewWrapper(AnySymbolView wrappedKey) {
                 super(wrappedKey);
         }
 
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/TermEvaluator.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/TermEvaluator.java
index ab123c50..1187f57a 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/TermEvaluator.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/TermEvaluator.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.pquery;
 
 import org.eclipse.viatra.query.runtime.matchers.psystem.IExpressionEvaluator;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/ValueProviderBasedValuation.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/ValueProviderBasedValuation.java
index 30c2fce7..62cb8b3a 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/ValueProviderBasedValuation.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/ValueProviderBasedValuation.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.pquery;
 
 import org.eclipse.viatra.query.runtime.matchers.psystem.IValueProvider;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/ModelUpdateListener.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/ModelUpdateListener.java
index fc935aa6..986bb0b1 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/ModelUpdateListener.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/ModelUpdateListener.java
@@ -1,46 +1,51 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.update;
 
 import org.eclipse.viatra.query.runtime.matchers.context.IInputKey;
 import org.eclipse.viatra.query.runtime.matchers.context.IQueryRuntimeContextListener;
 import org.eclipse.viatra.query.runtime.matchers.tuple.ITuple;
 import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
-import tools.refinery.store.query.view.AnyRelationView;
-import tools.refinery.store.query.view.RelationView;
+import tools.refinery.store.query.view.AnySymbolView;
+import tools.refinery.store.query.view.SymbolView;
 
 import java.util.HashMap;
 import java.util.Map;
 
 public class ModelUpdateListener {
-        private final Map<AnyRelationView, RelationViewUpdateListener<?>> relationViewUpdateListeners;
+        private final Map<AnySymbolView, SymbolViewUpdateListener<?>> symbolViewUpdateListeners;
 
         public ModelUpdateListener(ViatraModelQueryAdapterImpl adapter) {
-                var relationViews = adapter.getStoreAdapter().getInputKeys().keySet();
-                relationViewUpdateListeners = new HashMap<>(relationViews.size());
-                for (var relationView : relationViews) {
-                        registerView(adapter, (RelationView<?>) relationView);
+                var symbolViews = adapter.getStoreAdapter().getInputKeys().keySet();
+                symbolViewUpdateListeners = new HashMap<>(symbolViews.size());
+                for (var symbolView : symbolViews) {
+                        registerView(adapter, (SymbolView<?>) symbolView);
                 }
         }
 
-        private <T> void registerView(ViatraModelQueryAdapterImpl adapter, RelationView<T> relationView) {
+        private <T> void registerView(ViatraModelQueryAdapterImpl adapter, SymbolView<T> view) {
                 var model = adapter.getModel();
-                var interpretation = model.getInterpretation(relationView.getSymbol());
-                var listener = RelationViewUpdateListener.of(adapter, relationView, interpretation);
-                relationViewUpdateListeners.put(relationView, listener);
+                var interpretation = model.getInterpretation(view.getSymbol());
+                var listener = SymbolViewUpdateListener.of(adapter, view, interpretation);
+                symbolViewUpdateListeners.put(view, listener);
         }
 
-        public boolean containsRelationView(AnyRelationView relationView) {
-                return relationViewUpdateListeners.containsKey(relationView);
+        public boolean containsSymbolView(AnySymbolView relationView) {
+                return symbolViewUpdateListeners.containsKey(relationView);
         }
 
-        public void addListener(IInputKey key, AnyRelationView relationView, ITuple seed,
+        public void addListener(IInputKey key, AnySymbolView symbolView, ITuple seed,
                                                         IQueryRuntimeContextListener listener) {
-                var relationViewUpdateListener = relationViewUpdateListeners.get(relationView);
-                relationViewUpdateListener.addFilter(key, seed, listener);
+                var symbolViewUpdateListener = symbolViewUpdateListeners.get(symbolView);
+                symbolViewUpdateListener.addFilter(key, seed, listener);
         }
 
-        public void removeListener(IInputKey key, AnyRelationView relationView, ITuple seed,
+        public void removeListener(IInputKey key, AnySymbolView symbolView, ITuple seed,
                                                            IQueryRuntimeContextListener listener) {
-                var relationViewUpdateListener = relationViewUpdateListeners.get(relationView);
-                relationViewUpdateListener.removeFilter(key, seed, listener);
+                var symbolViewUpdateListener = symbolViewUpdateListeners.get(symbolView);
+                symbolViewUpdateListener.removeFilter(key, seed, listener);
         }
 }
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/RelationViewFilter.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/RelationViewFilter.java
index 221f1b4a..efdbfcbe 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/RelationViewFilter.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/RelationViewFilter.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.update;
 
 import org.eclipse.viatra.query.runtime.matchers.context.IInputKey;
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/RelationViewUpdateListener.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/SymbolViewUpdateListener.java
index 5e5f60e3..f1a2ac7c 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/RelationViewUpdateListener.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/SymbolViewUpdateListener.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.update;
 
 import org.eclipse.viatra.query.runtime.matchers.context.IInputKey;
@@ -7,18 +12,18 @@ import org.eclipse.viatra.query.runtime.matchers.tuple.Tuple;
 import tools.refinery.store.model.Interpretation;
 import tools.refinery.store.model.InterpretationListener;
 import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
-import tools.refinery.store.query.view.RelationView;
-import tools.refinery.store.query.view.TuplePreservingRelationView;
+import tools.refinery.store.query.view.SymbolView;
+import tools.refinery.store.query.view.TuplePreservingView;
 
 import java.util.ArrayList;
 import java.util.List;
 
-public abstract class RelationViewUpdateListener<T> implements InterpretationListener<T> {
+public abstract class SymbolViewUpdateListener<T> implements InterpretationListener<T> {
         private final ViatraModelQueryAdapterImpl adapter;
         private final Interpretation<T> interpretation;
         private final List<RelationViewFilter> filters = new ArrayList<>();
 
-        protected RelationViewUpdateListener(ViatraModelQueryAdapterImpl adapter, Interpretation<T> interpretation) {
+        protected SymbolViewUpdateListener(ViatraModelQueryAdapterImpl adapter, Interpretation<T> interpretation) {
                 this.adapter = adapter;
                 this.interpretation = interpretation;
         }
@@ -48,13 +53,13 @@ public abstract class RelationViewUpdateListener<T> implements InterpretationLis
                 }
         }
 
-        public static <T> RelationViewUpdateListener<T> of(ViatraModelQueryAdapterImpl adapter,
-                                                                                                           RelationView<T> relationView,
-                                                                                                           Interpretation<T> interpretation) {
-                if (relationView instanceof TuplePreservingRelationView<T> tuplePreservingRelationView) {
-                        return new TuplePreservingRelationViewUpdateListener<>(adapter, tuplePreservingRelationView,
+        public static <T> SymbolViewUpdateListener<T> of(ViatraModelQueryAdapterImpl adapter,
+                                                                                                         SymbolView<T> view,
+                                                                                                         Interpretation<T> interpretation) {
+                if (view instanceof TuplePreservingView<T> tuplePreservingRelationView) {
+                        return new TuplePreservingViewUpdateListener<>(adapter, tuplePreservingRelationView,
                                         interpretation);
                 }
-                return new TupleChangingRelationViewUpdateListener<>(adapter, relationView, interpretation);
+                return new TupleChangingViewUpdateListener<>(adapter, view, interpretation);
         }
 }
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TupleChangingRelationViewUpdateListener.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TupleChangingRelationViewUpdateListener.java
deleted file mode 100644
index 0f6ed3b3..00000000
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TupleChangingRelationViewUpdateListener.java
+++ /dev/null
@@ -1,39 +0,0 @@
-package tools.refinery.store.query.viatra.internal.update;
-
-import org.eclipse.viatra.query.runtime.matchers.tuple.Tuples;
-import tools.refinery.store.model.Interpretation;
-import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
-import tools.refinery.store.query.view.RelationView;
-import tools.refinery.store.tuple.Tuple;
-
-import java.util.Arrays;
-
-public class TupleChangingRelationViewUpdateListener<T> extends RelationViewUpdateListener<T> {
-        private final RelationView<T> relationView;
-
-        TupleChangingRelationViewUpdateListener(ViatraModelQueryAdapterImpl adapter, RelationView<T> relationView,
-                                                                                        Interpretation<T> interpretation) {
-        super(adapter, interpretation);
-        this.relationView = relationView;
-        }
-
-        @Override
-        public void put(Tuple key, T fromValue, T toValue, boolean restoring) {
-                boolean fromPresent = relationView.filter(key, fromValue);
-                boolean toPresent = relationView.filter(key, toValue);
-                if (fromPresent) {
-                        if (toPresent) { // value change
-                                var fromArray = relationView.forwardMap(key, fromValue);
-                                var toArray = relationView.forwardMap(key, toValue);
-                                if (!Arrays.equals(fromArray, toArray)) {
-                                        processUpdate(Tuples.flatTupleOf(fromArray), false);
-                                        processUpdate(Tuples.flatTupleOf(toArray), true);
-                                }
-                        } else { // fromValue disappears
-                                processUpdate(Tuples.flatTupleOf(relationView.forwardMap(key, fromValue)), false);
-                        }
-                } else if (toPresent) { // toValue appears
-                        processUpdate(Tuples.flatTupleOf(relationView.forwardMap(key, toValue)), true);
-                }
-        }
-}
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TupleChangingViewUpdateListener.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TupleChangingViewUpdateListener.java
new file mode 100644
index 00000000..45d35571
--- /dev/null
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TupleChangingViewUpdateListener.java
@@ -0,0 +1,44 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.viatra.internal.update;
+
+import org.eclipse.viatra.query.runtime.matchers.tuple.Tuples;
+import tools.refinery.store.model.Interpretation;
+import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
+import tools.refinery.store.query.view.SymbolView;
+import tools.refinery.store.tuple.Tuple;
+
+import java.util.Arrays;
+
+public class TupleChangingViewUpdateListener<T> extends SymbolViewUpdateListener<T> {
+        private final SymbolView<T> view;
+
+        TupleChangingViewUpdateListener(ViatraModelQueryAdapterImpl adapter, SymbolView<T> view,
+                                                                        Interpretation<T> interpretation) {
+        super(adapter, interpretation);
+        this.view = view;
+        }
+
+        @Override
+        public void put(Tuple key, T fromValue, T toValue, boolean restoring) {
+                boolean fromPresent = view.filter(key, fromValue);
+                boolean toPresent = view.filter(key, toValue);
+                if (fromPresent) {
+                        if (toPresent) { // value change
+                                var fromArray = view.forwardMap(key, fromValue);
+                                var toArray = view.forwardMap(key, toValue);
+                                if (!Arrays.equals(fromArray, toArray)) {
+                                        processUpdate(Tuples.flatTupleOf(fromArray), false);
+                                        processUpdate(Tuples.flatTupleOf(toArray), true);
+                                }
+                        } else { // fromValue disappears
+                                processUpdate(Tuples.flatTupleOf(view.forwardMap(key, fromValue)), false);
+                        }
+                } else if (toPresent) { // toValue appears
+                        processUpdate(Tuples.flatTupleOf(view.forwardMap(key, toValue)), true);
+                }
+        }
+}
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TuplePreservingRelationViewUpdateListener.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TuplePreservingViewUpdateListener.java
index 91e9371b..c18dbafb 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TuplePreservingRelationViewUpdateListener.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TuplePreservingViewUpdateListener.java
@@ -1,16 +1,21 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.internal.update;
 
 import org.eclipse.viatra.query.runtime.matchers.tuple.Tuples;
 import tools.refinery.store.model.Interpretation;
 import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
-import tools.refinery.store.query.view.TuplePreservingRelationView;
+import tools.refinery.store.query.view.TuplePreservingView;
 import tools.refinery.store.tuple.Tuple;
 
-public class TuplePreservingRelationViewUpdateListener<T> extends RelationViewUpdateListener<T> {
-        private final TuplePreservingRelationView<T> view;
+public class TuplePreservingViewUpdateListener<T> extends SymbolViewUpdateListener<T> {
+        private final TuplePreservingView<T> view;
 
-        TuplePreservingRelationViewUpdateListener(ViatraModelQueryAdapterImpl adapter,
-                                                                                          TuplePreservingRelationView<T> view, Interpretation<T> interpretation) {
+        TuplePreservingViewUpdateListener(ViatraModelQueryAdapterImpl adapter, TuplePreservingView<T> view,
+                                                                          Interpretation<T> interpretation) {
         super(adapter, interpretation);
         this.view = view;
         }
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/DiagonalQueryTest.java b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/DiagonalQueryTest.java
index 90229b73..6aae2ebe 100644
--- a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/DiagonalQueryTest.java
+++ b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/DiagonalQueryTest.java
@@ -1,17 +1,23 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra;
 
 import org.eclipse.viatra.query.runtime.matchers.backend.QueryEvaluationHint;
 import tools.refinery.store.model.ModelStore;
-import tools.refinery.store.query.ModelQuery;
+import tools.refinery.store.query.ModelQueryAdapter;
 import tools.refinery.store.query.dnf.Dnf;
 import tools.refinery.store.query.dnf.Query;
-import tools.refinery.store.query.term.Variable;
 import tools.refinery.store.query.viatra.tests.QueryEngineTest;
-import tools.refinery.store.query.view.FunctionalRelationView;
-import tools.refinery.store.query.view.KeyOnlyRelationView;
+import tools.refinery.store.query.view.AnySymbolView;
+import tools.refinery.store.query.view.FunctionView;
+import tools.refinery.store.query.view.KeyOnlyView;
 import tools.refinery.store.representation.Symbol;
 import tools.refinery.store.tuple.Tuple;
 
+import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 
@@ -21,34 +27,33 @@ import static tools.refinery.store.query.viatra.tests.QueryAssertions.assertNull
 import static tools.refinery.store.query.viatra.tests.QueryAssertions.assertResults;
 
 class DiagonalQueryTest {
+        private static final Symbol<Boolean> person = Symbol.of("Person", 1);
+        private static final Symbol<Boolean> friend = Symbol.of("friend", 2);
+        private static final Symbol<Boolean> symbol = Symbol.of("symbol", 4);
+        private static final Symbol<Integer> intSymbol = Symbol.of("intSymbol", 4, Integer.class);
+        private static final AnySymbolView personView = new KeyOnlyView<>(person);
+        private static final AnySymbolView friendView = new KeyOnlyView<>(friend);
+        private static final AnySymbolView symbolView = new KeyOnlyView<>(symbol);
+        private static final FunctionView<Integer> intSymbolView = new FunctionView<>(intSymbol);
+
         @QueryEngineTest
         void inputKeyNegationTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var symbol = new Symbol<>("symbol", 4, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-                var symbolView = new KeyOnlyRelationView<>(symbol);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var query = Query.builder("Diagonal")
-                                .parameter(p1)
-                                .clause(
-                                                personView.call(p1),
-                                                not(symbolView.call(p1, p1, p2, p2))
-                                )
-                                .build();
+                var query = Query.of("Diagonal", (builder, p1) -> builder.clause(p2 -> List.of(
+                                personView.call(p1),
+                                not(symbolView.call(p1, p1, p2, p2))
+                )));
 
                 var store = ModelStore.builder()
                                 .symbols(person, symbol)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var symbolInterpretation = model.getInterpretation(symbol);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -71,17 +76,7 @@ class DiagonalQueryTest {
 
         @QueryEngineTest
         void subQueryNegationTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var symbol = new Symbol<>("symbol", 4, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-                var symbolView = new KeyOnlyRelationView<>(symbol);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var p3 = Variable.of("p3");
-                var p4 = Variable.of("p4");
-                var subQuery = Dnf.builder("SubQuery")
-                                .parameters(p1, p2, p3, p4)
+                var subQuery = Query.of("SubQuery", (builder, p1, p2, p3, p4) -> builder
                                 .clause(
                                                 personView.call(p1),
                                                 symbolView.call(p1, p2, p3, p4)
@@ -89,27 +84,23 @@ class DiagonalQueryTest {
                                 .clause(
                                                 personView.call(p2),
                                                 symbolView.call(p1, p2, p3, p4)
-                                )
-                                .build();
-                var query = Query.builder("Diagonal")
-                                .parameter(p1)
-                                .clause(
-                                                personView.call(p1),
-                                                not(subQuery.call(p1, p1, p2, p2))
-                                )
-                                .build();
+                                ));
+                var query = Query.of("Diagonal", (builder, p1) -> builder.clause(p2 -> List.of(
+                                personView.call(p1),
+                                not(subQuery.call(p1, p1, p2, p2))
+                )));
 
                 var store = ModelStore.builder()
                                 .symbols(person, symbol)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var symbolInterpretation = model.getInterpretation(symbol);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -132,34 +123,22 @@ class DiagonalQueryTest {
 
         @QueryEngineTest
         void inputKeyCountTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var symbol = new Symbol<>("symbol", 4, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-                var symbolView = new KeyOnlyRelationView<>(symbol);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var x = Variable.of("x", Integer.class);
-                var query = Query.builder("Diagonal")
-                                .parameter(p1)
-                                .output(x)
-                                .clause(
-                                                personView.call(p1),
-                                                x.assign(symbolView.count(p1, p1, p2, p2))
-                                )
-                                .build();
+                var query = Query.of("Diagonal", Integer.class, (builder, p1, output) -> builder.clause(p2 -> List.of(
+                                personView.call(p1),
+                                output.assign(symbolView.count(p1, p1, p2, p2))
+                )));
 
                 var store = ModelStore.builder()
                                 .symbols(person, symbol)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var symbolInterpretation = model.getInterpretation(symbol);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -183,47 +162,30 @@ class DiagonalQueryTest {
 
         @QueryEngineTest
         void subQueryCountTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var symbol = new Symbol<>("symbol", 4, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-                var symbolView = new KeyOnlyRelationView<>(symbol);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var p3 = Variable.of("p3");
-                var p4 = Variable.of("p4");
-                var x = Variable.of("x", Integer.class);
-                var subQuery = Dnf.builder("SubQuery")
-                                .parameters(p1, p2, p3, p4)
-                                .clause(
+                var subQuery = Query.of("SubQuery", (builder, p1, p2, p3, p4) -> builder.clause(
                                                 personView.call(p1),
                                                 symbolView.call(p1, p2, p3, p4)
                                 )
                                 .clause(
                                                 personView.call(p2),
                                                 symbolView.call(p1, p2, p3, p4)
-                                )
-                                .build();
-                var query = Query.builder("Diagonal")
-                                .parameter(p1)
-                                .output(x)
-                                .clause(
-                                                personView.call(p1),
-                                                x.assign(subQuery.count(p1, p1, p2, p2))
-                                )
-                                .build();
+                                ));
+                var query = Query.of("Diagonal", Integer.class, (builder, p1, output) -> builder.clause(p2 -> List.of(
+                                personView.call(p1),
+                                output.assign(subQuery.count(p1, p1, p2, p2))
+                )));
 
                 var store = ModelStore.builder()
                                 .symbols(person, symbol)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var symbolInterpretation = model.getInterpretation(symbol);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -247,46 +209,34 @@ class DiagonalQueryTest {
 
         @QueryEngineTest
         void inputKeyAggregationTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var symbol = new Symbol<>("symbol", 4, Integer.class, null);
-                var personView = new KeyOnlyRelationView<>(person);
-                var symbolView = new FunctionalRelationView<>(symbol);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var x = Variable.of("x", Integer.class);
-                var y = Variable.of("y", Integer.class);
-                var query = Query.builder("Diagonal")
-                                .parameter(p1)
-                                .output(x)
-                                .clause(
+                var query = Query.of("Diagonal", Integer.class, (builder, p1, output) -> builder
+                                .clause((p2) -> List.of(
                                                 personView.call(p1),
-                                                x.assign(symbolView.aggregate(y, INT_SUM, p1, p1, p2, p2, y))
-                                )
-                                .build();
+                                                output.assign(intSymbolView.aggregate(INT_SUM, p1, p1, p2, p2))
+                                )));
 
                 var store = ModelStore.builder()
-                                .symbols(person, symbol)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .symbols(person, intSymbol)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
-                var symbolInterpretation = model.getInterpretation(symbol);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var intSymbolInterpretation = model.getInterpretation(intSymbol);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
                 personInterpretation.put(Tuple.of(1), true);
                 personInterpretation.put(Tuple.of(2), true);
 
-                symbolInterpretation.put(Tuple.of(0, 0, 1, 1), 1);
-                symbolInterpretation.put(Tuple.of(0, 0, 2, 2), 2);
-                symbolInterpretation.put(Tuple.of(0, 0, 1, 2), 10);
-                symbolInterpretation.put(Tuple.of(1, 1, 0, 1), 11);
-                symbolInterpretation.put(Tuple.of(1, 2, 1, 1), 12);
+                intSymbolInterpretation.put(Tuple.of(0, 0, 1, 1), 1);
+                intSymbolInterpretation.put(Tuple.of(0, 0, 2, 2), 2);
+                intSymbolInterpretation.put(Tuple.of(0, 0, 1, 2), 10);
+                intSymbolInterpretation.put(Tuple.of(1, 1, 0, 1), 11);
+                intSymbolInterpretation.put(Tuple.of(1, 2, 1, 1), 12);
 
                 queryEngine.flushChanges();
                 assertNullableResults(Map.of(
@@ -299,62 +249,52 @@ class DiagonalQueryTest {
 
         @QueryEngineTest
         void subQueryAggregationTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var symbol = new Symbol<>("symbol", 4, Integer.class, null);
-                var personView = new KeyOnlyRelationView<>(person);
-                var symbolView = new FunctionalRelationView<>(symbol);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var p3 = Variable.of("p3");
-                var p4 = Variable.of("p4");
-                var x = Variable.of("x", Integer.class);
-                var y = Variable.of("y", Integer.class);
-                var z = Variable.of("z", Integer.class);
-                var subQuery = Dnf.builder("SubQuery")
-                                .parameters(p1, p2, p3, p4, x, y)
-                                .clause(
+                var subQuery = Dnf.of("SubQuery", builder -> {
+                        var p1 = builder.parameter("p1");
+                        var p2 = builder.parameter("p2");
+                        var p3 = builder.parameter("p3");
+                        var p4 = builder.parameter("p4");
+                        var x = builder.parameter("x", Integer.class);
+                        var y = builder.parameter("y", Integer.class);
+                        builder.clause(
+                                        personView.call(p1),
+                                        intSymbolView.call(p1, p2, p3, p4, x),
+                                        y.assign(x)
+                        );
+                        builder.clause(
+                                        personView.call(p2),
+                                        intSymbolView.call(p1, p2, p3, p4, x),
+                                        y.assign(x)
+                        );
+                });
+                var query = Query.of("Diagonal", Integer.class, (builder, p1, output) -> builder
+                                .clause(Integer.class, Integer.class, (p2, y, z) -> List.of(
                                                 personView.call(p1),
-                                                symbolView.call(p1, p2, p3, p4, x),
-                                                y.assign(x)
-                                )
-                                .clause(
-                                                personView.call(p2),
-                                                symbolView.call(p1, p2, p3, p4, x),
-                                                y.assign(x)
-                                )
-                                .build();
-                var query = Query.builder("Diagonal")
-                                .parameter(p1)
-                                .output(x)
-                                .clause(
-                                                personView.call(p1),
-                                                x.assign(subQuery.aggregate(z, INT_SUM, p1, p1, p2, p2, z, z))
-                                )
-                                .build();
+                                                output.assign(subQuery.aggregateBy(y, INT_SUM, p1, p1, p2, p2, y, z))
+                                )));
 
                 var store = ModelStore.builder()
-                                .symbols(person, symbol)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .symbols(person, intSymbol)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
-                var symbolInterpretation = model.getInterpretation(symbol);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var intSymbolInterpretation = model.getInterpretation(intSymbol);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
                 personInterpretation.put(Tuple.of(1), true);
                 personInterpretation.put(Tuple.of(2), true);
 
-                symbolInterpretation.put(Tuple.of(0, 0, 1, 1), 1);
-                symbolInterpretation.put(Tuple.of(0, 0, 2, 2), 2);
-                symbolInterpretation.put(Tuple.of(0, 0, 1, 2), 10);
-                symbolInterpretation.put(Tuple.of(1, 1, 0, 1), 11);
-                symbolInterpretation.put(Tuple.of(1, 2, 1, 1), 12);
+                intSymbolInterpretation.put(Tuple.of(0, 0, 1, 1), 1);
+                intSymbolInterpretation.put(Tuple.of(0, 0, 2, 2), 2);
+                intSymbolInterpretation.put(Tuple.of(0, 0, 1, 2), 10);
+                intSymbolInterpretation.put(Tuple.of(1, 1, 0, 1), 11);
+                intSymbolInterpretation.put(Tuple.of(1, 2, 1, 1), 12);
 
                 queryEngine.flushChanges();
                 assertNullableResults(Map.of(
@@ -367,40 +307,31 @@ class DiagonalQueryTest {
 
         @QueryEngineTest
         void inputKeyTransitiveTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var symbol = new Symbol<>("symbol", 2, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-                var symbolView = new KeyOnlyRelationView<>(symbol);
-
-                var p1 = Variable.of("p1");
-                var query = Query.builder("Diagonal")
-                                .parameter(p1)
-                                .clause(
-                                                personView.call(p1),
-                                                symbolView.callTransitive(p1, p1)
-                                )
-                                .build();
+                var query = Query.of("Diagonal", (builder, p1) -> builder.clause(
+                                personView.call(p1),
+                                friendView.callTransitive(p1, p1)
+                ));
 
                 var store = ModelStore.builder()
-                                .symbols(person, symbol)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .symbols(person, friend)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
-                var symbolInterpretation = model.getInterpretation(symbol);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var friendInterpretation = model.getInterpretation(friend);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
                 personInterpretation.put(Tuple.of(1), true);
                 personInterpretation.put(Tuple.of(2), true);
 
-                symbolInterpretation.put(Tuple.of(0, 0), true);
-                symbolInterpretation.put(Tuple.of(0, 1), true);
-                symbolInterpretation.put(Tuple.of(1, 2), true);
+                friendInterpretation.put(Tuple.of(0, 0), true);
+                friendInterpretation.put(Tuple.of(0, 1), true);
+                friendInterpretation.put(Tuple.of(1, 2), true);
 
                 queryEngine.flushChanges();
                 assertResults(Map.of(
@@ -413,52 +344,40 @@ class DiagonalQueryTest {
 
         @QueryEngineTest
         void subQueryTransitiveTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var symbol = new Symbol<>("symbol", 2, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-                var symbolView = new KeyOnlyRelationView<>(symbol);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var subQuery = Dnf.builder("SubQuery")
-                                .parameters(p1, p2)
+                var subQuery = Query.of("SubQuery", (builder, p1, p2) -> builder
                                 .clause(
                                                 personView.call(p1),
-                                                symbolView.call(p1, p2)
+                                                friendView.call(p1, p2)
                                 )
                                 .clause(
                                                 personView.call(p2),
-                                                symbolView.call(p1, p2)
-                                )
-                                .build();
-                var query = Query.builder("Diagonal")
-                                .parameter(p1)
-                                .clause(
-                                                personView.call(p1),
-                                                subQuery.callTransitive(p1, p1)
-                                )
-                                .build();
+                                                friendView.call(p1, p2)
+                                ));
+                var query = Query.of("Diagonal", (builder, p1) -> builder.clause(
+                                personView.call(p1),
+                                subQuery.callTransitive(p1, p1)
+                ));
 
                 var store = ModelStore.builder()
-                                .symbols(person, symbol)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .symbols(person, friend)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
-                var symbolInterpretation = model.getInterpretation(symbol);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var friendInterpretation = model.getInterpretation(friend);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
                 personInterpretation.put(Tuple.of(1), true);
                 personInterpretation.put(Tuple.of(2), true);
 
-                symbolInterpretation.put(Tuple.of(0, 0), true);
-                symbolInterpretation.put(Tuple.of(0, 1), true);
-                symbolInterpretation.put(Tuple.of(1, 2), true);
+                friendInterpretation.put(Tuple.of(0, 0), true);
+                friendInterpretation.put(Tuple.of(0, 1), true);
+                friendInterpretation.put(Tuple.of(1, 2), true);
 
                 queryEngine.flushChanges();
                 assertResults(Map.of(
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/FunctionalQueryTest.java b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/FunctionalQueryTest.java
index fa2a008f..258127e7 100644
--- a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/FunctionalQueryTest.java
+++ b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/FunctionalQueryTest.java
@@ -1,20 +1,26 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra;
 
 import org.eclipse.viatra.query.runtime.matchers.backend.QueryEvaluationHint;
 import tools.refinery.store.map.Cursor;
 import tools.refinery.store.model.ModelStore;
-import tools.refinery.store.query.ModelQuery;
-import tools.refinery.store.query.dnf.Dnf;
+import tools.refinery.store.query.ModelQueryAdapter;
 import tools.refinery.store.query.dnf.Query;
 import tools.refinery.store.query.term.Variable;
 import tools.refinery.store.query.viatra.tests.QueryEngineTest;
-import tools.refinery.store.query.view.FilteredRelationView;
-import tools.refinery.store.query.view.FunctionalRelationView;
-import tools.refinery.store.query.view.KeyOnlyRelationView;
+import tools.refinery.store.query.view.AnySymbolView;
+import tools.refinery.store.query.view.FilteredView;
+import tools.refinery.store.query.view.FunctionView;
+import tools.refinery.store.query.view.KeyOnlyView;
 import tools.refinery.store.representation.Symbol;
 import tools.refinery.store.representation.TruthValue;
 import tools.refinery.store.tuple.Tuple;
 
+import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 
@@ -29,35 +35,31 @@ import static tools.refinery.store.query.viatra.tests.QueryAssertions.assertNull
 import static tools.refinery.store.query.viatra.tests.QueryAssertions.assertResults;
 
 class FunctionalQueryTest {
+        private static final Symbol<Boolean> person = Symbol.of("Person", 1);
+        private static final Symbol<Integer> age = Symbol.of("age", 1, Integer.class);
+        private static final Symbol<TruthValue> friend = Symbol.of("friend", 2, TruthValue.class, TruthValue.FALSE);
+        private static final AnySymbolView personView = new KeyOnlyView<>(person);
+        private static final FunctionView<Integer> ageView = new FunctionView<>(age);
+        private static final AnySymbolView friendMustView = new FilteredView<>(friend, "must", TruthValue::must);
+
         @QueryEngineTest
         void inputKeyTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var personView = new KeyOnlyRelationView<>(person);
-                var ageView = new FunctionalRelationView<>(age);
-
-                var p1 = Variable.of("p1");
-                var x = Variable.of("x", Integer.class);
-                var query = Query.builder("InputKey")
-                                .parameter(p1)
-                                .output(x)
-                                .clause(
-                                                personView.call(p1),
-                                                ageView.call(p1, x)
-                                )
-                                .build();
+                var query = Query.of("InputKey", Integer.class, (builder, p1, output) -> builder.clause(
+                                personView.call(p1),
+                                ageView.call(p1, output)
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, age)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var ageInterpretation = model.getInterpretation(age);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -77,40 +79,26 @@ class FunctionalQueryTest {
 
         @QueryEngineTest
         void predicateTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var personView = new KeyOnlyRelationView<>(person);
-                var ageView = new FunctionalRelationView<>(age);
-
-                var p1 = Variable.of("p1");
-                var x = Variable.of("x", Integer.class);
-                var subQuery = Dnf.builder("SubQuery")
-                                .parameters(p1, x)
-                                .clause(
-                                                personView.call(p1),
-                                                ageView.call(p1, x)
-                                )
-                                .build();
-                var query = Query.builder("Predicate")
-                                .parameter(p1)
-                                .output(x)
-                                .clause(
-                                                personView.call(p1),
-                                                subQuery.call(p1, x)
-                                )
-                                .build();
+                var subQuery = Query.of("SubQuery", Integer.class, (builder, p1, x) -> builder.clause(
+                                personView.call(p1),
+                                ageView.call(p1, x)
+                ));
+                var query = Query.of("Predicate", Integer.class, (builder, p1, output) -> builder.clause(
+                                personView.call(p1),
+                                output.assign(subQuery.call(p1))
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, age)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var ageInterpretation = model.getInterpretation(age);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -130,35 +118,26 @@ class FunctionalQueryTest {
 
         @QueryEngineTest
         void computationTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var personView = new KeyOnlyRelationView<>(person);
-                var ageView = new FunctionalRelationView<>(age);
-
-                var p1 = Variable.of("p1");
-                var x = Variable.of("x", Integer.class);
-                var y = Variable.of("y", Integer.class);
-                var query = Query.builder("Computation")
-                                .parameter(p1)
-                                .output(y)
-                                .clause(
-                                                personView.call(p1),
-                                                ageView.call(p1, x),
-                                                y.assign(mul(x, constant(7)))
-                                )
-                                .build();
+                var query = Query.of("Computation", Integer.class, (builder, p1, output) -> builder.clause(() -> {
+                        var x = Variable.of("x", Integer.class);
+                        return List.of(
+                                        personView.call(p1),
+                                        ageView.call(p1, x),
+                                        output.assign(mul(x, constant(7)))
+                        );
+                }));
 
                 var store = ModelStore.builder()
                                 .symbols(person, age)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var ageInterpretation = model.getInterpretation(age);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -177,34 +156,22 @@ class FunctionalQueryTest {
 
         @QueryEngineTest
         void inputKeyCountTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var x = Variable.of("x", Integer.class);
-                var query = Query.builder("Count")
-                                .parameter(p1)
-                                .output(x)
-                                .clause(
-                                                personView.call(p1),
-                                                x.assign(friendMustView.count(p1, p2))
-                                )
-                                .build();
+                var query = Query.of("Count", Integer.class, (builder, p1, output) -> builder.clause(
+                                personView.call(p1),
+                                output.assign(friendMustView.count(p1, Variable.of()))
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -226,42 +193,27 @@ class FunctionalQueryTest {
 
         @QueryEngineTest
         void predicateCountTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var x = Variable.of("x", Integer.class);
-                var subQuery = Dnf.builder("SubQuery")
-                                .parameters(p1, p2)
-                                .clause(
-                                                personView.call(p1),
-                                                personView.call(p2),
-                                                friendMustView.call(p1, p2)
-                                )
-                                .build();
-                var query = Query.builder("Count")
-                                .parameter(p1)
-                                .output(x)
-                                .clause(
-                                                personView.call(p1),
-                                                x.assign(subQuery.count(p1, p2))
-                                )
-                                .build();
+                var subQuery = Query.of("SubQuery", (builder, p1, p2) -> builder.clause(
+                                        personView.call(p1),
+                                        personView.call(p2),
+                                        friendMustView.call(p1, p2)
+                ));
+                var query = Query.of("Count", Integer.class, (builder, p1, output) -> builder.clause(
+                                personView.call(p1),
+                                output.assign(subQuery.count(p1, Variable.of()))
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -283,29 +235,20 @@ class FunctionalQueryTest {
 
         @QueryEngineTest
         void inputKeyAggregationTest(QueryEvaluationHint hint) {
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var ageView = new FunctionalRelationView<>(age);
-
-                var p1 = Variable.of("p1");
-                var x = Variable.of("x", Integer.class);
-                var y = Variable.of("y", Integer.class);
-                var query = Query.builder("Aggregate")
-                                .output(x)
-                                .clause(
-                                                x.assign(ageView.aggregate(y, INT_SUM, p1, y))
-                                )
-                                .build();
+                var query = Query.of("Aggregate", Integer.class, (builder, output) -> builder.clause(
+                                output.assign(ageView.aggregate(INT_SUM, Variable.of()))
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(age)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var ageInterpretation = model.getInterpretation(age);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 ageInterpretation.put(Tuple.of(0), 12);
@@ -317,39 +260,25 @@ class FunctionalQueryTest {
 
         @QueryEngineTest
         void predicateAggregationTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var personView = new KeyOnlyRelationView<>(person);
-                var ageView = new FunctionalRelationView<>(age);
-
-                var p1 = Variable.of("p1");
-                var x = Variable.of("x", Integer.class);
-                var y = Variable.of("y", Integer.class);
-                var subQuery = Dnf.builder("SubQuery")
-                                .parameters(p1, x)
-                                .clause(
-                                                personView.call(p1),
-                                                ageView.call(p1, x)
-                                )
-                                .build();
-                var query = Query.builder("Aggregate")
-                                .output(x)
-                                .clause(
-                                                x.assign(subQuery.aggregate(y, INT_SUM, p1, y))
-                                )
-                                .build();
+                var subQuery = Query.of("SubQuery", Integer.class, (builder, p1, x) -> builder.clause(
+                                personView.call(p1),
+                                ageView.call(p1, x)
+                ));
+                var query = Query.of("Aggregate", Integer.class, (builder, output) -> builder.clause(
+                                output.assign(subQuery.aggregate(INT_SUM, Variable.of()))
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, age)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var ageInterpretation = model.getInterpretation(age);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -364,46 +293,28 @@ class FunctionalQueryTest {
 
         @QueryEngineTest
         void extremeValueTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var x = Variable.of("x", Integer.class);
-                var y = Variable.of("y", Integer.class);
-                var subQuery = Dnf.builder("SubQuery")
-                                .parameters(p1, x)
-                                .clause(
-                                                personView.call(p1),
-                                                x.assign(friendMustView.count(p1, p2))
-                                )
-                                .build();
-                var minQuery = Query.builder("Min")
-                                .output(x)
-                                .clause(
-                                                x.assign(subQuery.aggregate(y, INT_MIN, p1, y))
-                                )
-                                .build();
-                var maxQuery = Query.builder("Max")
-                                .output(x)
-                                .clause(
-                                                x.assign(subQuery.aggregate(y, INT_MAX, p1, y))
-                                )
-                                .build();
+                var subQuery = Query.of("SubQuery", Integer.class, (builder, p1, x) -> builder.clause(
+                                personView.call(p1),
+                                x.assign(friendMustView.count(p1, Variable.of()))
+                ));
+                var minQuery = Query.of("Min", Integer.class, (builder, output) -> builder.clause(
+                                output.assign(subQuery.aggregate(INT_MIN, Variable.of()))
+                ));
+                var maxQuery = Query.of("Max", Integer.class, (builder, output) -> builder.clause(
+                                output.assign(subQuery.aggregate(INT_MAX, Variable.of()))
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(minQuery, maxQuery)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(minQuery, maxQuery))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var minResultSet = queryEngine.getResultSet(minQuery);
                 var maxResultSet = queryEngine.getResultSet(maxQuery);
 
@@ -440,35 +351,24 @@ class FunctionalQueryTest {
 
         @QueryEngineTest
         void invalidComputationTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var personView = new KeyOnlyRelationView<>(person);
-                var ageView = new FunctionalRelationView<>(age);
-
-                var p1 = Variable.of("p1");
-                var x = Variable.of("x", Integer.class);
-                var y = Variable.of("y", Integer.class);
-                var query = Query.builder("InvalidComputation")
-                                .parameter(p1)
-                                .output(y)
-                                .clause(
+                var query = Query.of("InvalidComputation", Integer.class,
+                                (builder, p1, output) -> builder.clause(Integer.class, (x) -> List.of(
                                                 personView.call(p1),
                                                 ageView.call(p1, x),
-                                                y.assign(div(constant(120), x))
-                                )
-                                .build();
+                                                output.assign(div(constant(120), x))
+                                )));
 
                 var store = ModelStore.builder()
                                 .symbols(person, age)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var ageInterpretation = model.getInterpretation(age);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -487,33 +387,23 @@ class FunctionalQueryTest {
 
         @QueryEngineTest
         void invalidAssumeTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var personView = new KeyOnlyRelationView<>(person);
-                var ageView = new FunctionalRelationView<>(age);
-
-                var p1 = Variable.of("p1");
-                var x = Variable.of("x", Integer.class);
-                var query = Query.builder("InvalidComputation")
-                                .parameter(p1)
-                                .clause(
-                                                personView.call(p1),
-                                                ageView.call(p1, x),
-                                                assume(lessEq(div(constant(120), x), constant(5)))
-                                )
-                                .build();
+                var query = Query.of("InvalidAssume", (builder, p1) -> builder.clause(Integer.class, (x) -> List.of(
+                                personView.call(p1),
+                                ageView.call(p1, x),
+                                assume(lessEq(div(constant(120), x), constant(5)))
+                )));
 
                 var store = ModelStore.builder()
                                 .symbols(person, age)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var ageInterpretation = model.getInterpretation(age);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -535,38 +425,24 @@ class FunctionalQueryTest {
 
         @QueryEngineTest
         void notFunctionalTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var ageView = new FunctionalRelationView<>(age);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var x = Variable.of("x", Integer.class);
-                var query = Query.builder("NotFunctional")
-                                .parameter(p1)
-                                .output(x)
-                                .clause(
-                                                personView.call(p1),
-                                                friendMustView.call(p1, p2),
-                                                ageView.call(p2, x)
-                                )
-                                .build();
+                var query = Query.of("NotFunctional", Integer.class, (builder, p1, output) -> builder.clause((p2) -> List.of(
+                                personView.call(p1),
+                                friendMustView.call(p1, p2),
+                                ageView.call(p2, output)
+                )));
 
                 var store = ModelStore.builder()
                                 .symbols(person, age, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .query(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var ageInterpretation = model.getInterpretation(age);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/QueryTest.java b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/QueryTest.java
index 8a3f9d88..297cdf04 100644
--- a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/QueryTest.java
+++ b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/QueryTest.java
@@ -1,23 +1,28 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra;
 
 import org.eclipse.viatra.query.runtime.matchers.backend.QueryEvaluationHint;
 import org.junit.jupiter.api.Test;
 import tools.refinery.store.model.ModelStore;
-import tools.refinery.store.query.ModelQuery;
-import tools.refinery.store.query.dnf.Dnf;
+import tools.refinery.store.query.ModelQueryAdapter;
 import tools.refinery.store.query.dnf.Query;
 import tools.refinery.store.query.term.Variable;
 import tools.refinery.store.query.viatra.tests.QueryEngineTest;
-import tools.refinery.store.query.view.FilteredRelationView;
-import tools.refinery.store.query.view.FunctionalRelationView;
-import tools.refinery.store.query.view.KeyOnlyRelationView;
+import tools.refinery.store.query.view.AnySymbolView;
+import tools.refinery.store.query.view.FilteredView;
+import tools.refinery.store.query.view.FunctionView;
+import tools.refinery.store.query.view.KeyOnlyView;
 import tools.refinery.store.representation.Symbol;
 import tools.refinery.store.representation.TruthValue;
 import tools.refinery.store.tuple.Tuple;
 
+import java.util.List;
 import java.util.Map;
 
-import static org.junit.jupiter.api.Assertions.assertThrows;
 import static tools.refinery.store.query.literal.Literals.assume;
 import static tools.refinery.store.query.literal.Literals.not;
 import static tools.refinery.store.query.term.int_.IntTerms.constant;
@@ -25,29 +30,28 @@ import static tools.refinery.store.query.term.int_.IntTerms.greaterEq;
 import static tools.refinery.store.query.viatra.tests.QueryAssertions.assertResults;
 
 class QueryTest {
+        private static final Symbol<Boolean> person = Symbol.of("Person", 1);
+        private static final Symbol<TruthValue> friend = Symbol.of("friend", 2, TruthValue.class, TruthValue.FALSE);
+        private static final AnySymbolView personView = new KeyOnlyView<>(person);
+        private static final AnySymbolView friendMustView = new FilteredView<>(friend, "must", TruthValue::must);
+
         @QueryEngineTest
         void typeConstraintTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var asset = new Symbol<>("Asset", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-
-                var p1 = Variable.of("p1");
-                var predicate = Query.builder("TypeConstraint")
-                                .parameters(p1)
-                                .clause(personView.call(p1))
-                                .build();
+                var asset = Symbol.of("Asset", 1);
+
+                var predicate = Query.of("TypeConstraint", (builder, p1) -> builder.clause(personView.call(p1)));
 
                 var store = ModelStore.builder()
                                 .symbols(person, asset)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .query(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var assetInterpretation = model.getInterpretation(asset);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -66,33 +70,23 @@ class QueryTest {
 
         @QueryEngineTest
         void relationConstraintTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var predicate = Query.builder("RelationConstraint")
-                                .parameters(p1, p2)
-                                .clause(
-                                                personView.call(p1),
-                                                personView.call(p2),
-                                                friendMustView.call(p1, p2)
-                                )
-                                .build();
+                var predicate = Query.of("RelationConstraint", (builder, p1, p2) -> builder.clause(
+                                personView.call(p1),
+                                personView.call(p2),
+                                friendMustView.call(p1, p2)
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -115,33 +109,23 @@ class QueryTest {
 
         @QueryEngineTest
         void existTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var predicate = Query.builder("RelationConstraint")
-                                .parameters(p1)
-                                .clause(
-                                                personView.call(p1),
-                                                personView.call(p2),
-                                                friendMustView.call(p1, p2)
-                                )
-                                .build();
+                var predicate = Query.of("Exists", (builder, p1) -> builder.clause((p2) -> List.of(
+                                personView.call(p1),
+                                personView.call(p2),
+                                friendMustView.call(p1, p2)
+                )));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -164,41 +148,31 @@ class QueryTest {
 
         @QueryEngineTest
         void orTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var animal = new Symbol<>("Animal", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var animalView = new KeyOnlyRelationView<>(animal);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var predicate = Query.builder("Or")
-                                .parameters(p1, p2)
-                                .clause(
-                                                personView.call(p1),
-                                                personView.call(p2),
-                                                friendMustView.call(p1, p2)
-                                )
-                                .clause(
-                                                animalView.call(p1),
-                                                animalView.call(p2),
-                                                friendMustView.call(p1, p2)
-                                )
-                                .build();
+                var animal = Symbol.of("Animal", 1);
+                var animalView = new KeyOnlyView<>(animal);
+
+                var predicate = Query.of("Or", (builder, p1, p2) -> builder.clause(
+                                personView.call(p1),
+                                personView.call(p2),
+                                friendMustView.call(p1, p2)
+                ).clause(
+                                animalView.call(p1),
+                                animalView.call(p2),
+                                friendMustView.call(p1, p2)
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, animal, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var animalInterpretation = model.getInterpretation(animal);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -224,30 +198,22 @@ class QueryTest {
 
         @QueryEngineTest
         void equalityTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var predicate = Query.builder("Equality")
-                                .parameters(p1, p2)
-                                .clause(
-                                                personView.call(p1),
-                                                personView.call(p2),
-                                                p1.isEquivalent(p2)
-                                )
-                                .build();
+                var predicate = Query.of("Equality", (builder, p1, p2) -> builder.clause(
+                                personView.call(p1),
+                                personView.call(p2),
+                                p1.isEquivalent(p2)
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -266,36 +232,25 @@ class QueryTest {
 
         @QueryEngineTest
         void inequalityTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var p3 = Variable.of("p3");
-                var predicate = Query.builder("Inequality")
-                                .parameters(p1, p2, p3)
-                                .clause(
-                                                personView.call(p1),
-                                                personView.call(p2),
-                                                friendMustView.call(p1, p3),
-                                                friendMustView.call(p2, p3),
-                                                p1.notEquivalent(p2)
-                                )
-                                .build();
+                var predicate = Query.of("Inequality", (builder, p1, p2, p3) -> builder.clause(
+                                personView.call(p1),
+                                personView.call(p2),
+                                friendMustView.call(p1, p3),
+                                friendMustView.call(p2, p3),
+                                p1.notEquivalent(p2)
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -315,44 +270,28 @@ class QueryTest {
 
         @QueryEngineTest
         void patternCallTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var friendPredicate = Dnf.builder("RelationConstraint")
-                                .parameters(p1, p2)
-                                .clause(
-                                                personView.call(p1),
-                                                personView.call(p2),
-                                                friendMustView.call(p1, p2)
-                                )
-                                .build();
-
-                var p3 = Variable.of("p3");
-                var p4 = Variable.of("p4");
-                var predicate = Query.builder("PositivePatternCall")
-                                .parameters(p3, p4)
-                                .clause(
-                                                personView.call(p3),
-                                                personView.call(p4),
-                                                friendPredicate.call(p3, p4)
-                                )
-                                .build();
+                var friendPredicate = Query.of("Friend", (builder, p1, p2) -> builder.clause(
+                                personView.call(p1),
+                                personView.call(p2),
+                                friendMustView.call(p1, p2)
+                ));
+                var predicate = Query.of("PositivePatternCall", (builder, p3, p4) -> builder.clause(
+                                personView.call(p3),
+                                personView.call(p4),
+                                friendPredicate.call(p3, p4)
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -374,33 +313,23 @@ class QueryTest {
 
         @QueryEngineTest
         void negativeRelationViewTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var predicate = Query.builder("NegativePatternCall")
-                                .parameters(p1, p2)
-                                .clause(
-                                                personView.call(p1),
-                                                personView.call(p2),
-                                                not(friendMustView.call(p1, p2))
-                                )
-                                .build();
+                var predicate = Query.of("NegativePatternCall", (builder, p1, p2) -> builder.clause(
+                                personView.call(p1),
+                                personView.call(p2),
+                                not(friendMustView.call(p1, p2))
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -428,44 +357,28 @@ class QueryTest {
 
         @QueryEngineTest
         void negativePatternCallTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var friendPredicate = Dnf.builder("RelationConstraint")
-                                .parameters(p1, p2)
-                                .clause(
-                                                personView.call(p1),
-                                                personView.call(p2),
-                                                friendMustView.call(p1, p2)
-                                )
-                                .build();
-
-                var p3 = Variable.of("p3");
-                var p4 = Variable.of("p4");
-                var predicate = Query.builder("NegativePatternCall")
-                                .parameters(p3, p4)
-                                .clause(
-                                                personView.call(p3),
-                                                personView.call(p4),
-                                                not(friendPredicate.call(p3, p4))
-                                )
-                                .build();
+                var friendPredicate = Query.of("Friend", (builder, p1, p2) -> builder.clause(
+                                personView.call(p1),
+                                personView.call(p2),
+                                friendMustView.call(p1, p2)
+                ));
+                var predicate = Query.of("NegativePatternCall", (builder, p3, p4) -> builder.clause(
+                                personView.call(p3),
+                                personView.call(p4),
+                                not(friendPredicate.call(p3, p4))
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -493,33 +406,22 @@ class QueryTest {
 
         @QueryEngineTest
         void negativeRelationViewWithQuantificationTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-
-                var predicate = Query.builder("Count")
-                                .parameters(p1)
-                                .clause(
-                                                personView.call(p1),
-                                                not(friendMustView.call(p1, p2))
-                                )
-                                .build();
+                var predicate = Query.of("Negative", (builder, p1) -> builder.clause(
+                                personView.call(p1),
+                                not(friendMustView.call(p1, Variable.of()))
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -540,42 +442,27 @@ class QueryTest {
 
         @QueryEngineTest
         void negativeWithQuantificationTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-
-                var called = Dnf.builder("Called")
-                                .parameters(p1, p2)
-                                .clause(
-                                                personView.call(p1),
-                                                personView.call(p2),
-                                                friendMustView.call(p1, p2)
-                                )
-                                .build();
-
-                var predicate = Query.builder("Count")
-                                .parameters(p1)
-                                .clause(
-                                                personView.call(p1),
-                                                not(called.call(p1, p2))
-                                )
-                                .build();
+                var called = Query.of("Called", (builder, p1, p2) -> builder.clause(
+                                personView.call(p1),
+                                personView.call(p2),
+                                friendMustView.call(p1, p2)
+                ));
+                var predicate = Query.of("Negative", (builder, p1) -> builder.clause(
+                                personView.call(p1),
+                                not(called.call(p1, Variable.of()))
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -596,33 +483,23 @@ class QueryTest {
 
         @QueryEngineTest
         void transitiveRelationViewTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var predicate = Query.builder("TransitivePatternCall")
-                                .parameters(p1, p2)
-                                .clause(
-                                                personView.call(p1),
-                                                personView.call(p2),
-                                                friendMustView.callTransitive(p1, p2)
-                                )
-                                .build();
+                var predicate = Query.of("Transitive", (builder, p1, p2) -> builder.clause(
+                                personView.call(p1),
+                                personView.call(p2),
+                                friendMustView.callTransitive(p1, p2)
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -649,44 +526,28 @@ class QueryTest {
 
         @QueryEngineTest
         void transitivePatternCallTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, TruthValue.class, TruthValue.FALSE);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friendMustView = new FilteredRelationView<>(friend, "must", TruthValue::must);
-
-                var p1 = Variable.of("p1");
-                var p2 = Variable.of("p2");
-                var friendPredicate = Dnf.builder("RelationConstraint")
-                                .parameters(p1, p2)
-                                .clause(
-                                                personView.call(p1),
-                                                personView.call(p2),
-                                                friendMustView.call(p1, p2)
-                                )
-                                .build();
-
-                var p3 = Variable.of("p3");
-                var p4 = Variable.of("p4");
-                var predicate = Query.builder("TransitivePatternCall")
-                                .parameters(p3, p4)
-                                .clause(
-                                                personView.call(p3),
-                                                personView.call(p4),
-                                                friendPredicate.callTransitive(p3, p4)
-                                )
-                                .build();
+                var called = Query.of("Called", (builder, p1, p2) -> builder.clause(
+                                personView.call(p1),
+                                personView.call(p2),
+                                friendMustView.call(p1, p2)
+                ));
+                var predicate = Query.of("Transitive", (builder, p1, p2) -> builder.clause(
+                                personView.call(p1),
+                                personView.call(p2),
+                                called.callTransitive(p1, p2)
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, friend)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var friendInterpretation = model.getInterpretation(friend);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -713,33 +574,26 @@ class QueryTest {
 
         @QueryEngineTest
         void assumeTest(QueryEvaluationHint hint) {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var personView = new KeyOnlyRelationView<>(person);
-                var ageView = new FunctionalRelationView<>(age);
-
-                var p1 = Variable.of("p1");
-                var x = Variable.of("x", Integer.class);
-                var query = Query.builder("Constraint")
-                                .parameter(p1)
-                                .clause(
-                                                personView.call(p1),
-                                                ageView.call(p1, x),
-                                                assume(greaterEq(x, constant(18)))
-                                )
-                                .build();
+                var age = Symbol.of("age", 1, Integer.class);
+                var ageView = new FunctionView<>(age);
+
+                var query = Query.of("Constraint", (builder, p1) -> builder.clause(Integer.class, (x) -> List.of(
+                                personView.call(p1),
+                                ageView.call(p1, x),
+                                assume(greaterEq(x, constant(18)))
+                )));
 
                 var store = ModelStore.builder()
                                 .symbols(person, age)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(hint)
-                                .queries(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var ageInterpretation = model.getInterpretation(age);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -758,20 +612,17 @@ class QueryTest {
 
         @Test
         void alwaysFalseTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-
-                var p1 = Variable.of("p1");
-                var predicate = Query.builder("AlwaysFalse").parameters(p1).build();
+                var predicate = Query.of("AlwaysFalse", builder -> builder.parameter("p1"));
 
                 var store = ModelStore.builder()
                                 .symbols(person)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -781,17 +632,4 @@ class QueryTest {
                 queryEngine.flushChanges();
                 assertResults(Map.of(), predicateResultSet);
         }
-
-        @Test
-        void alwaysTrueTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-
-                var p1 = Variable.of("p1");
-                var predicate = Query.builder("AlwaysTrue").parameters(p1).clause().build();
-
-                var storeBuilder = ModelStore.builder().symbols(person);
-                var queryBuilder = storeBuilder.with(ViatraModelQuery.ADAPTER);
-
-                assertThrows(IllegalArgumentException.class, () -> queryBuilder.queries(predicate));
-        }
 }
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/QueryTransactionTest.java b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/QueryTransactionTest.java
index abd49341..66f043c6 100644
--- a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/QueryTransactionTest.java
+++ b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/QueryTransactionTest.java
@@ -1,15 +1,21 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra;
 
 import org.eclipse.viatra.query.runtime.matchers.backend.QueryEvaluationHint;
 import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 import tools.refinery.store.model.ModelStore;
-import tools.refinery.store.query.ModelQuery;
+import tools.refinery.store.query.ModelQueryAdapter;
 import tools.refinery.store.query.dnf.Query;
-import tools.refinery.store.query.term.Variable;
-import tools.refinery.store.query.view.FilteredRelationView;
-import tools.refinery.store.query.view.FunctionalRelationView;
-import tools.refinery.store.query.view.KeyOnlyRelationView;
+import tools.refinery.store.query.dnf.RelationalQuery;
+import tools.refinery.store.query.view.AnySymbolView;
+import tools.refinery.store.query.view.FilteredView;
+import tools.refinery.store.query.view.FunctionView;
+import tools.refinery.store.query.view.KeyOnlyView;
 import tools.refinery.store.representation.Symbol;
 import tools.refinery.store.tuple.Tuple;
 
@@ -22,26 +28,24 @@ import static tools.refinery.store.query.viatra.tests.QueryAssertions.assertNull
 import static tools.refinery.store.query.viatra.tests.QueryAssertions.assertResults;
 
 class QueryTransactionTest {
+        private static final Symbol<Boolean> person = Symbol.of("Person", 1);
+        private static final Symbol<Integer> age = Symbol.of("age", 1, Integer.class);
+        private static final AnySymbolView personView = new KeyOnlyView<>(person);
+        private static final AnySymbolView ageView = new FunctionView<>(age);
+        private static final RelationalQuery predicate = Query.of("TypeConstraint", (builder, p1) ->
+                        builder.clause(personView.call(p1)));
+
         @Test
         void flushTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-
-                var p1 = Variable.of("p1");
-                var predicate = Query.builder("TypeConstraint")
-                                .parameters(p1)
-                                .clause(personView.call(p1))
-                                .build();
-
                 var store = ModelStore.builder()
                                 .symbols(person)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 assertResults(Map.of(
@@ -95,25 +99,16 @@ class QueryTransactionTest {
 
         @Test
         void localSearchTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-
-                var p1 = Variable.of("p1");
-                var predicate = Query.builder("TypeConstraint")
-                                .parameters(p1)
-                                .clause(personView.call(p1))
-                                .build();
-
                 var store = ModelStore.builder()
                                 .symbols(person)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .defaultHint(new QueryEvaluationHint(null, QueryEvaluationHint.BackendRequirement.DEFAULT_SEARCH))
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                        .defaultHint(new QueryEvaluationHint(null, QueryEvaluationHint.BackendRequirement.DEFAULT_SEARCH))
+                                        .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 assertResults(Map.of(
@@ -149,26 +144,18 @@ class QueryTransactionTest {
 
         @Test
         void unrelatedChangesTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var asset = new Symbol<>("Asset", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-
-                var p1 = Variable.of("p1");
-                var predicate = Query.builder("TypeConstraint")
-                                .parameters(p1)
-                                .clause(personView.call(p1))
-                                .build();
+                var asset = Symbol.of("Asset", 1);
 
                 var store = ModelStore.builder()
                                 .symbols(person, asset)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var assetInterpretation = model.getInterpretation(asset);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 assertFalse(queryEngine.hasPendingChanges());
@@ -222,32 +209,21 @@ class QueryTransactionTest {
 
         @Test
         void tupleChangingChangeTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var personView = new KeyOnlyRelationView<>(person);
-                var ageView = new FunctionalRelationView<>(age);
-
-                var p1 = Variable.of("p1");
-                var x = Variable.of("x", Integer.class);
-                var query = Query.builder()
-                                .parameter(p1)
-                                .output(x)
-                                .clause(
-                                                personView.call(p1),
-                                                ageView.call(p1, x)
-                                )
-                                .build();
+                var query = Query.of("TypeConstraint", Integer.class, (builder, p1, output) -> builder.clause(
+                                personView.call(p1),
+                                ageView.call(p1, output)
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, age)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .query(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var ageInterpretation = model.getInterpretation(age);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -270,31 +246,23 @@ class QueryTransactionTest {
 
         @Test
         void tuplePreservingUnchangedTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var personView = new KeyOnlyRelationView<>(person);
-                var adultView = new FilteredRelationView<>(age, "adult", n -> n != null && n >= 18);
-
-                var p1 = Variable.of("p1");
-                var x = Variable.of("x", Integer.class);
-                var query = Query.builder()
-                                .parameter(p1)
-                                .clause(
-                                                personView.call(p1),
-                                                adultView.call(p1)
-                                )
-                                .build();
+                var adultView = new FilteredView<>(age, "adult", n -> n != null && n >= 18);
+
+                var query = Query.of("TypeConstraint", (builder, p1) -> builder.clause(
+                                personView.call(p1),
+                                adultView.call(p1)
+                ));
 
                 var store = ModelStore.builder()
                                 .symbols(person, age)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .query(query)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .queries(query))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
                 var ageInterpretation = model.getInterpretation(age);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var queryResultSet = queryEngine.getResultSet(query);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -318,24 +286,15 @@ class QueryTransactionTest {
         @Disabled("TODO Fix DiffCursor")
         @Test
         void commitAfterFlushTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-
-                var p1 = Variable.of("p1");
-                var predicate = Query.builder("TypeConstraint")
-                                .parameters(p1)
-                                .clause(personView.call(p1))
-                                .build();
-
                 var store = ModelStore.builder()
                                 .symbols(person)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
@@ -376,24 +335,15 @@ class QueryTransactionTest {
         @Disabled("TODO Fix DiffCursor")
         @Test
         void commitWithoutFlushTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-
-                var p1 = Variable.of("p1");
-                var predicate = Query.builder("TypeConstraint")
-                                .parameters(p1)
-                                .clause(personView.call(p1))
-                                .build();
-
                 var store = ModelStore.builder()
                                 .symbols(person)
-                                .with(ViatraModelQuery.ADAPTER)
-                                .queries(predicate)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .queries(predicate))
                                 .build();
 
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
-                var queryEngine = model.getAdapter(ModelQuery.ADAPTER);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 personInterpretation.put(Tuple.of(0), true);
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/internal/cardinality/UpperCardinalitySumAggregationOperatorTest.java b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/internal/cardinality/UpperCardinalitySumAggregationOperatorTest.java
deleted file mode 100644
index 20dad543..00000000
--- a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/internal/cardinality/UpperCardinalitySumAggregationOperatorTest.java
+++ /dev/null
@@ -1,87 +0,0 @@
-package tools.refinery.store.query.viatra.internal.cardinality;
-
-import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.Test;
-import tools.refinery.store.representation.cardinality.UpperCardinalities;
-import tools.refinery.store.representation.cardinality.UpperCardinality;
-
-import static org.hamcrest.MatcherAssert.assertThat;
-import static org.hamcrest.Matchers.equalTo;
-
-class UpperCardinalitySumAggregationOperatorTest {
-        private UpperCardinalitySumAggregationOperator.Accumulator accumulator;
-
-        @BeforeEach
-        void beforeEach() {
-                accumulator = UpperCardinalitySumAggregationOperator.INSTANCE.createNeutral();
-        }
-
-        @Test
-        void emptyAggregationTest() {
-                assertResult(UpperCardinality.of(0));
-        }
-
-        @Test
-        void singleBoundedTest() {
-                insert(UpperCardinality.of(3));
-                assertResult(UpperCardinality.of(3));
-        }
-
-        @Test
-        void multipleBoundedTest() {
-                insert(UpperCardinality.of(2));
-                insert(UpperCardinality.of(3));
-                assertResult(UpperCardinality.of(5));
-        }
-
-        @Test
-        void singleUnboundedTest() {
-                insert(UpperCardinalities.UNBOUNDED);
-                assertResult(UpperCardinalities.UNBOUNDED);
-        }
-
-        @Test
-        void multipleUnboundedTest() {
-                insert(UpperCardinalities.UNBOUNDED);
-                insert(UpperCardinalities.UNBOUNDED);
-                assertResult(UpperCardinalities.UNBOUNDED);
-        }
-
-        @Test
-        void removeBoundedTest() {
-                insert(UpperCardinality.of(2));
-                insert(UpperCardinality.of(3));
-                remove(UpperCardinality.of(2));
-                assertResult(UpperCardinality.of(3));
-        }
-
-        @Test
-        void removeAllUnboundedTest() {
-                insert(UpperCardinalities.UNBOUNDED);
-                insert(UpperCardinality.of(3));
-                remove(UpperCardinalities.UNBOUNDED);
-                assertResult(UpperCardinality.of(3));
-        }
-
-        @Test
-        void removeSomeUnboundedTest() {
-                insert(UpperCardinalities.UNBOUNDED);
-                insert(UpperCardinalities.UNBOUNDED);
-                insert(UpperCardinality.of(3));
-                remove(UpperCardinalities.UNBOUNDED);
-                assertResult(UpperCardinalities.UNBOUNDED);
-        }
-
-        private void insert(UpperCardinality value) {
-                accumulator = UpperCardinalitySumAggregationOperator.INSTANCE.update(accumulator, value, true);
-        }
-
-        private void remove(UpperCardinality value) {
-                accumulator = UpperCardinalitySumAggregationOperator.INSTANCE.update(accumulator, value, false);
-        }
-
-        private void assertResult(UpperCardinality expected) {
-                var result = UpperCardinalitySumAggregationOperator.INSTANCE.getAggregate(accumulator);
-                assertThat(result, equalTo(expected));
-        }
-}
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/internal/matcher/MatcherUtilsTest.java b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/internal/matcher/MatcherUtilsTest.java
new file mode 100644
index 00000000..968c6c5e
--- /dev/null
+++ b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/internal/matcher/MatcherUtilsTest.java
@@ -0,0 +1,239 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.viatra.internal.matcher;
+
+import org.eclipse.viatra.query.runtime.matchers.tuple.*;
+import org.junit.jupiter.api.Test;
+import tools.refinery.store.tuple.Tuple;
+import tools.refinery.store.tuple.*;
+
+import java.util.List;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.*;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class MatcherUtilsTest {
+        @Test
+        void toViatra0Test() {
+                var viatraTuple = MatcherUtils.toViatraTuple(Tuple.of());
+                assertThat(viatraTuple.getSize(), is(0));
+                assertThat(viatraTuple, instanceOf(FlatTuple0.class));
+        }
+
+        @Test
+        void toViatra1Test() {
+                var viatraTuple = MatcherUtils.toViatraTuple(Tuple.of(2));
+                assertThat(viatraTuple.getSize(), is(1));
+                assertThat(viatraTuple.get(0), is(Tuple.of(2)));
+                assertThat(viatraTuple, instanceOf(FlatTuple1.class));
+        }
+
+        @Test
+        void toViatra2Test() {
+                var viatraTuple = MatcherUtils.toViatraTuple(Tuple.of(2, 3));
+                assertThat(viatraTuple.getSize(), is(2));
+                assertThat(viatraTuple.get(0), is(Tuple.of(2)));
+                assertThat(viatraTuple.get(1), is(Tuple.of(3)));
+                assertThat(viatraTuple, instanceOf(FlatTuple2.class));
+        }
+
+        @Test
+        void toViatra3Test() {
+                var viatraTuple = MatcherUtils.toViatraTuple(Tuple.of(2, 3, 5));
+                assertThat(viatraTuple.getSize(), is(3));
+                assertThat(viatraTuple.get(0), is(Tuple.of(2)));
+                assertThat(viatraTuple.get(1), is(Tuple.of(3)));
+                assertThat(viatraTuple.get(2), is(Tuple.of(5)));
+                assertThat(viatraTuple, instanceOf(FlatTuple3.class));
+        }
+
+        @Test
+        void toViatra4Test() {
+                var viatraTuple = MatcherUtils.toViatraTuple(Tuple.of(2, 3, 5, 8));
+                assertThat(viatraTuple.getSize(), is(4));
+                assertThat(viatraTuple.get(0), is(Tuple.of(2)));
+                assertThat(viatraTuple.get(1), is(Tuple.of(3)));
+                assertThat(viatraTuple.get(2), is(Tuple.of(5)));
+                assertThat(viatraTuple.get(3), is(Tuple.of(8)));
+                assertThat(viatraTuple, instanceOf(FlatTuple4.class));
+        }
+
+        @Test
+        void toViatra5Test() {
+                var viatraTuple = MatcherUtils.toViatraTuple(Tuple.of(2, 3, 5, 8, 13));
+                assertThat(viatraTuple.getSize(), is(5));
+                assertThat(viatraTuple.get(0), is(Tuple.of(2)));
+                assertThat(viatraTuple.get(1), is(Tuple.of(3)));
+                assertThat(viatraTuple.get(2), is(Tuple.of(5)));
+                assertThat(viatraTuple.get(3), is(Tuple.of(8)));
+                assertThat(viatraTuple.get(4), is(Tuple.of(13)));
+                assertThat(viatraTuple, instanceOf(FlatTuple.class));
+        }
+
+        @Test
+        void toRefinery0Test() {
+                var refineryTuple = MatcherUtils.toRefineryTuple(Tuples.flatTupleOf());
+                assertThat(refineryTuple.getSize(), is(0));
+                assertThat(refineryTuple, instanceOf(Tuple0.class));
+        }
+
+        @Test
+        void toRefinery1Test() {
+                var refineryTuple = MatcherUtils.toRefineryTuple(Tuples.flatTupleOf(Tuple.of(2)));
+                assertThat(refineryTuple.getSize(), is(1));
+                assertThat(refineryTuple.get(0), is(2));
+                assertThat(refineryTuple, instanceOf(Tuple1.class));
+        }
+
+        @Test
+        void toRefinery2Test() {
+                var refineryTuple = MatcherUtils.toRefineryTuple(Tuples.flatTupleOf(Tuple.of(2), Tuple.of(3)));
+                assertThat(refineryTuple.getSize(), is(2));
+                assertThat(refineryTuple.get(0), is(2));
+                assertThat(refineryTuple.get(1), is(3));
+                assertThat(refineryTuple, instanceOf(Tuple2.class));
+        }
+
+        @Test
+        void toRefinery3Test() {
+                var refineryTuple = MatcherUtils.toRefineryTuple(Tuples.flatTupleOf(Tuple.of(2), Tuple.of(3), Tuple.of(5)));
+                assertThat(refineryTuple.getSize(), is(3));
+                assertThat(refineryTuple.get(0), is(2));
+                assertThat(refineryTuple.get(1), is(3));
+                assertThat(refineryTuple.get(2), is(5));
+                assertThat(refineryTuple, instanceOf(Tuple3.class));
+        }
+
+        @Test
+        void toRefinery4Test() {
+                var refineryTuple = MatcherUtils.toRefineryTuple(Tuples.flatTupleOf(Tuple.of(2), Tuple.of(3), Tuple.of(5),
+                                Tuple.of(8)));
+                assertThat(refineryTuple.getSize(), is(4));
+                assertThat(refineryTuple.get(0), is(2));
+                assertThat(refineryTuple.get(1), is(3));
+                assertThat(refineryTuple.get(2), is(5));
+                assertThat(refineryTuple.get(3), is(8));
+                assertThat(refineryTuple, instanceOf(Tuple4.class));
+        }
+
+        @Test
+        void toRefinery5Test() {
+                var refineryTuple = MatcherUtils.toRefineryTuple(Tuples.flatTupleOf(Tuple.of(2), Tuple.of(3), Tuple.of(5),
+                                Tuple.of(8), Tuple.of(13)));
+                assertThat(refineryTuple.getSize(), is(5));
+                assertThat(refineryTuple.get(0), is(2));
+                assertThat(refineryTuple.get(1), is(3));
+                assertThat(refineryTuple.get(2), is(5));
+                assertThat(refineryTuple.get(3), is(8));
+                assertThat(refineryTuple.get(4), is(13));
+                assertThat(refineryTuple, instanceOf(TupleN.class));
+        }
+
+        @Test
+        void toRefineryInvalidValueTest() {
+                var viatraTuple = Tuples.flatTupleOf(Tuple.of(2), -98);
+                assertThrows(IllegalArgumentException.class, () -> MatcherUtils.toRefineryTuple(viatraTuple));
+        }
+
+        @Test
+        void keyToRefinery0Test() {
+                var refineryTuple = MatcherUtils.keyToRefineryTuple(Tuples.flatTupleOf(-99));
+                assertThat(refineryTuple.getSize(), is(0));
+                assertThat(refineryTuple, instanceOf(Tuple0.class));
+        }
+
+        @Test
+        void keyToRefinery1Test() {
+                var refineryTuple = MatcherUtils.keyToRefineryTuple(Tuples.flatTupleOf(Tuple.of(2), -99));
+                assertThat(refineryTuple.getSize(), is(1));
+                assertThat(refineryTuple.get(0), is(2));
+                assertThat(refineryTuple, instanceOf(Tuple1.class));
+        }
+
+        @Test
+        void keyToRefinery2Test() {
+                var refineryTuple = MatcherUtils.keyToRefineryTuple(Tuples.flatTupleOf(Tuple.of(2), Tuple.of(3), -99));
+                assertThat(refineryTuple.getSize(), is(2));
+                assertThat(refineryTuple.get(0), is(2));
+                assertThat(refineryTuple.get(1), is(3));
+                assertThat(refineryTuple, instanceOf(Tuple2.class));
+        }
+
+        @Test
+        void keyToRefinery3Test() {
+                var refineryTuple = MatcherUtils.keyToRefineryTuple(Tuples.flatTupleOf(Tuple.of(2), Tuple.of(3), Tuple.of(5),
+                                -99));
+                assertThat(refineryTuple.getSize(), is(3));
+                assertThat(refineryTuple.get(0), is(2));
+                assertThat(refineryTuple.get(1), is(3));
+                assertThat(refineryTuple.get(2), is(5));
+                assertThat(refineryTuple, instanceOf(Tuple3.class));
+        }
+
+        @Test
+        void keyToRefinery4Test() {
+                var refineryTuple = MatcherUtils.keyToRefineryTuple(Tuples.flatTupleOf(Tuple.of(2), Tuple.of(3), Tuple.of(5),
+                                Tuple.of(8), -99));
+                assertThat(refineryTuple.getSize(), is(4));
+                assertThat(refineryTuple.get(0), is(2));
+                assertThat(refineryTuple.get(1), is(3));
+                assertThat(refineryTuple.get(2), is(5));
+                assertThat(refineryTuple.get(3), is(8));
+                assertThat(refineryTuple, instanceOf(Tuple4.class));
+        }
+
+        @Test
+        void keyToRefinery5Test() {
+                var refineryTuple = MatcherUtils.keyToRefineryTuple(Tuples.flatTupleOf(Tuple.of(2), Tuple.of(3), Tuple.of(5),
+                                Tuple.of(8), Tuple.of(13), -99));
+                assertThat(refineryTuple.getSize(), is(5));
+                assertThat(refineryTuple.get(0), is(2));
+                assertThat(refineryTuple.get(1), is(3));
+                assertThat(refineryTuple.get(2), is(5));
+                assertThat(refineryTuple.get(3), is(8));
+                assertThat(refineryTuple.get(4), is(13));
+                assertThat(refineryTuple, instanceOf(TupleN.class));
+        }
+
+        @Test
+        void keyToRefineryTooShortTest() {
+                var viatraTuple = Tuples.flatTupleOf();
+                assertThrows(IllegalArgumentException.class, () -> MatcherUtils.keyToRefineryTuple(viatraTuple));
+        }
+
+        @Test
+        void keyToRefineryInvalidValueTest() {
+                var viatraTuple = Tuples.flatTupleOf(Tuple.of(2), -98, -99);
+                assertThrows(IllegalArgumentException.class, () -> MatcherUtils.keyToRefineryTuple(viatraTuple));
+        }
+
+        @Test
+        void getSingleValueTest() {
+                var value = MatcherUtils.getSingleValue(List.of(Tuples.flatTupleOf(Tuple.of(2), -99)));
+                assertThat(value, is(-99));
+        }
+
+        // Static analysis accurately determines that the result is always {@code null}, but we check anyways.
+        @SuppressWarnings("ConstantValue")
+        @Test
+        void getSingleValueNullTest() {
+                var value = MatcherUtils.getSingleValue((Iterable<? extends ITuple>) null);
+                assertThat(value, nullValue());
+        }
+
+        @Test
+        void getSingleValueEmptyTest() {
+                var value = MatcherUtils.getSingleValue(List.of());
+                assertThat(value, nullValue());
+        }
+
+        @Test
+        void getSingleValueMultipleTest() {
+                var viatraTuples = List.of(Tuples.flatTupleOf(Tuple.of(2), -98), Tuples.flatTupleOf(Tuple.of(2), -99));
+                assertThrows(IllegalStateException.class, () -> MatcherUtils.getSingleValue(viatraTuples));
+        }
+}
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryAssertions.java b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryAssertions.java
index 6f50ec73..7a25cfdc 100644
--- a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryAssertions.java
+++ b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryAssertions.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.tests;
 
 import org.junit.jupiter.api.function.Executable;
@@ -42,7 +47,7 @@ public final class QueryAssertions {
                 var cursor = resultSet.getAll();
                 while (cursor.move()) {
                         var key = cursor.getKey();
-                        var previous = actual.put(key.toTuple(), cursor.getValue());
+                        var previous = actual.put(key, cursor.getValue());
                         assertThat("duplicate value for key " + key, previous, nullValue());
                 }
                 executables.add(() -> assertThat("results cursor", actual, is(filteredExpected)));
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryBackendHint.java b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryBackendHint.java
index b1818a17..dc0e92c8 100644
--- a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryBackendHint.java
+++ b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryBackendHint.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.tests;
 
 import org.eclipse.viatra.query.runtime.matchers.backend.QueryEvaluationHint;
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryEngineTest.java b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryEngineTest.java
index f129520c..d4f16da7 100644
--- a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryEngineTest.java
+++ b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryEngineTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.tests;
 
 import org.junit.jupiter.params.ParameterizedTest;
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryEvaluationHintSource.java b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryEvaluationHintSource.java
index a55762e2..9e75d5f3 100644
--- a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryEvaluationHintSource.java
+++ b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/tests/QueryEvaluationHintSource.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.viatra.tests;
 
 import org.eclipse.viatra.query.runtime.matchers.backend.QueryEvaluationHint;
diff --git a/subprojects/store-query/build.gradle b/subprojects/store-query/build.gradle
deleted file mode 100644
index 97761936..00000000
--- a/subprojects/store-query/build.gradle
+++ /dev/null
@@ -1,9 +0,0 @@
-plugins {
-        id 'refinery-java-library'
-        id 'refinery-java-test-fixtures'
-}
-
-dependencies {
-        api project(':refinery-store')
-        testFixturesApi libs.hamcrest
-}
diff --git a/subprojects/store-query/build.gradle.kts b/subprojects/store-query/build.gradle.kts
new file mode 100644
index 00000000..4d8e2605
--- /dev/null
+++ b/subprojects/store-query/build.gradle.kts
@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+plugins {
+        id("tools.refinery.gradle.java-library")
+        id("tools.refinery.gradle.java-test-fixtures")
+}
+
+dependencies {
+        api(project(":refinery-store"))
+        testFixturesApi(libs.hamcrest)
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/AnyResultSet.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/AnyResultSet.java
index 6d411212..f29bb278 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/AnyResultSet.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/AnyResultSet.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query;
 
 import tools.refinery.store.query.dnf.AnyQuery;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/Constraint.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/Constraint.java
index cec4c19f..916fb35c 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/Constraint.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/Constraint.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query;
 
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
@@ -9,25 +14,27 @@ import java.util.List;
 public interface Constraint {
         String name();
 
-        List<Sort> getSorts();
+        List<Parameter> getParameters();
 
         default int arity() {
-                return getSorts().size();
+                return getParameters().size();
         }
 
         default boolean invalidIndex(int i) {
                 return i < 0 || i >= arity();
         }
 
-        default LiteralReduction getReduction() {
-                return LiteralReduction.NOT_REDUCIBLE;
+        default Reduction getReduction() {
+                return Reduction.NOT_REDUCIBLE;
         }
 
         default boolean equals(LiteralEqualityHelper helper, Constraint other) {
                 return equals(other);
         }
 
-        String toReferenceString();
+        default String toReferenceString() {
+                return name();
+        }
 
         default CallLiteral call(CallPolarity polarity, List<Variable> arguments) {
                 return new CallLiteral(polarity, this, arguments);
@@ -53,13 +60,13 @@ public interface Constraint {
                 return count(List.of(arguments));
         }
 
-        default <R, T> AssignedValue<R> aggregate(DataVariable<T> inputVariable, Aggregator<R, T> aggregator,
-                                                                                          List<Variable> arguments) {
+        default <R, T> AssignedValue<R> aggregateBy(DataVariable<T> inputVariable, Aggregator<R, T> aggregator,
+                                                                                                List<Variable> arguments) {
                 return targetVariable -> new AggregationLiteral<>(targetVariable, aggregator, inputVariable, this, arguments);
         }
 
-        default <R, T> AssignedValue<R> aggregate(DataVariable<T> inputVariable, Aggregator<R, T> aggregator,
-                                                                                          Variable... arguments) {
-                return aggregate(inputVariable, aggregator, List.of(arguments));
+        default <R, T> AssignedValue<R> aggregateBy(DataVariable<T> inputVariable, Aggregator<R, T> aggregator,
+                                                                                                Variable... arguments) {
+                return aggregateBy(inputVariable, aggregator, List.of(arguments));
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/EmptyResultSet.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/EmptyResultSet.java
index 9af73bdd..5361f645 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/EmptyResultSet.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/EmptyResultSet.java
@@ -1,9 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query;
 
 import tools.refinery.store.map.Cursor;
 import tools.refinery.store.map.Cursors;
 import tools.refinery.store.query.dnf.Query;
-import tools.refinery.store.tuple.TupleLike;
+import tools.refinery.store.tuple.Tuple;
 
 public record EmptyResultSet<T>(ModelQueryAdapter adapter, Query<T> query) implements ResultSet<T> {
         @Override
@@ -17,13 +22,12 @@ public record EmptyResultSet<T>(ModelQueryAdapter adapter, Query<T> query) imple
         }
 
         @Override
-        public T get(TupleLike parameters) {
+        public T get(Tuple parameters) {
                 return query.defaultValue();
         }
 
-
         @Override
-        public Cursor<TupleLike, T> getAll() {
+        public Cursor<Tuple, T> getAll() {
                 return Cursors.empty();
         }
 
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQuery.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQuery.java
deleted file mode 100644
index 6a1aeabb..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQuery.java
+++ /dev/null
@@ -1,11 +0,0 @@
-package tools.refinery.store.query;
-
-import tools.refinery.store.adapter.ModelAdapterType;
-
-public final class ModelQuery extends ModelAdapterType<ModelQueryAdapter, ModelQueryStoreAdapter, ModelQueryBuilder> {
-        public static final ModelQuery ADAPTER = new ModelQuery();
-
-        private ModelQuery() {
-                super(ModelQueryAdapter.class, ModelQueryStoreAdapter.class, ModelQueryBuilder.class);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQueryAdapter.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQueryAdapter.java
index 2e30fec4..ae3bbcbb 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQueryAdapter.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQueryAdapter.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query;
 
 import tools.refinery.store.adapter.ModelAdapter;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQueryBuilder.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQueryBuilder.java
index 4fdc9210..c62a95b5 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQueryBuilder.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQueryBuilder.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query;
 
 import tools.refinery.store.adapter.ModelAdapterBuilder;
@@ -21,5 +26,5 @@ public interface ModelQueryBuilder extends ModelAdapterBuilder {
         ModelQueryBuilder query(AnyQuery query);
 
         @Override
-        ModelQueryStoreAdapter createStoreAdapter(ModelStore store);
+        ModelQueryStoreAdapter build(ModelStore store);
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQueryStoreAdapter.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQueryStoreAdapter.java
index 514e582b..f0a950a6 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQueryStoreAdapter.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/ModelQueryStoreAdapter.java
@@ -1,14 +1,19 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query;
 
 import tools.refinery.store.adapter.ModelStoreAdapter;
 import tools.refinery.store.model.Model;
 import tools.refinery.store.query.dnf.AnyQuery;
-import tools.refinery.store.query.view.AnyRelationView;
+import tools.refinery.store.query.view.AnySymbolView;
 
 import java.util.Collection;
 
 public interface ModelQueryStoreAdapter extends ModelStoreAdapter {
-        Collection<AnyRelationView> getRelationViews();
+        Collection<AnySymbolView> getSymbolViews();
 
         Collection<AnyQuery> getQueries();
 
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/LiteralReduction.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/Reduction.java
index 146089f6..82c52b04 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/LiteralReduction.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/Reduction.java
@@ -1,6 +1,11 @@
-package tools.refinery.store.query.literal;
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query;
 
-public enum LiteralReduction {
+public enum Reduction {
         /**
          * Signifies that a literal should be preserved in the clause.
          */
@@ -16,7 +21,7 @@ public enum LiteralReduction {
          */
         ALWAYS_FALSE;
 
-        public LiteralReduction negate() {
+        public Reduction negate() {
                 return switch (this) {
                         case NOT_REDUCIBLE -> NOT_REDUCIBLE;
                         case ALWAYS_TRUE -> ALWAYS_FALSE;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/ResultSet.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/ResultSet.java
index 3f6bc06f..9ab83172 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/ResultSet.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/ResultSet.java
@@ -1,13 +1,18 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query;
 
 import tools.refinery.store.map.Cursor;
 import tools.refinery.store.query.dnf.Query;
-import tools.refinery.store.tuple.TupleLike;
+import tools.refinery.store.tuple.Tuple;
 
 public non-sealed interface ResultSet<T> extends AnyResultSet {
         Query<T> getQuery();
 
-        T get(TupleLike parameters);
+        T get(Tuple parameters);
 
-        Cursor<TupleLike, T> getAll();
+        Cursor<Tuple, T> getAll();
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/AbstractQueryBuilder.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/AbstractQueryBuilder.java
new file mode 100644
index 00000000..2a3e3ce0
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/AbstractQueryBuilder.java
@@ -0,0 +1,175 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf;
+
+import tools.refinery.store.query.dnf.callback.*;
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.ParameterDirection;
+import tools.refinery.store.query.term.Variable;
+
+import java.util.Collection;
+import java.util.List;
+import java.util.Set;
+
+public abstract class AbstractQueryBuilder<T extends AbstractQueryBuilder<T>> {
+        protected final DnfBuilder dnfBuilder;
+
+        protected AbstractQueryBuilder(DnfBuilder dnfBuilder) {
+                this.dnfBuilder = dnfBuilder;
+        }
+
+        protected abstract T self();
+
+        public NodeVariable parameter() {
+                return dnfBuilder.parameter();
+        }
+
+        public NodeVariable parameter(String name) {
+                return dnfBuilder.parameter(name);
+        }
+
+        public NodeVariable parameter(ParameterDirection direction) {
+                return dnfBuilder.parameter(direction);
+        }
+
+        public NodeVariable parameter(String name, ParameterDirection direction) {
+                return dnfBuilder.parameter(name, direction);
+        }
+
+        public T parameter(NodeVariable variable) {
+                dnfBuilder.parameter(variable);
+                return self();
+        }
+
+        public T parameter(NodeVariable variable, ParameterDirection direction) {
+                dnfBuilder.parameter(variable, direction);
+                return self();
+        }
+
+        public T parameters(NodeVariable... variables) {
+                dnfBuilder.parameters(variables);
+                return self();
+        }
+
+        public T parameters(List<NodeVariable> variables) {
+                dnfBuilder.parameters(variables);
+                return self();
+        }
+
+        public T parameters(List<NodeVariable> variables, ParameterDirection direction) {
+                dnfBuilder.parameters(variables, direction);
+                return self();
+        }
+
+        public T symbolicParameters(List<SymbolicParameter> parameters) {
+                dnfBuilder.symbolicParameters(parameters);
+                return self();
+        }
+
+        public T functionalDependencies(Collection<FunctionalDependency<Variable>> functionalDependencies) {
+                dnfBuilder.functionalDependencies(functionalDependencies);
+                return self();
+        }
+
+        public T functionalDependency(FunctionalDependency<Variable> functionalDependency) {
+                dnfBuilder.functionalDependency(functionalDependency);
+                return self();
+        }
+
+        public T functionalDependency(Set<? extends Variable> forEach, Set<? extends Variable> unique) {
+                dnfBuilder.functionalDependency(forEach, unique);
+                return self();
+        }
+
+        public T clause(ClauseCallback0 callback) {
+                dnfBuilder.clause(callback);
+                return self();
+        }
+
+        public T clause(ClauseCallback1Data0 callback) {
+                dnfBuilder.clause(callback);
+                return self();
+        }
+
+        public <U1> T clause(Class<U1> type1, ClauseCallback1Data1<U1> callback) {
+                dnfBuilder.clause(type1, callback);
+                return self();
+        }
+
+        public T clause(ClauseCallback2Data0 callback) {
+                dnfBuilder.clause(callback);
+                return self();
+        }
+
+        public <U1> T clause(Class<U1> type1, ClauseCallback2Data1<U1> callback) {
+                dnfBuilder.clause(type1, callback);
+                return self();
+        }
+
+        public <U1, U2> T clause(Class<U1> type1, Class<U2> type2, ClauseCallback2Data2<U1, U2> callback) {
+                dnfBuilder.clause(type1, type2, callback);
+                return self();
+        }
+
+        public T clause(ClauseCallback3Data0 callback) {
+                dnfBuilder.clause(callback);
+                return self();
+        }
+
+        public <U1> T clause(Class<U1> type1, ClauseCallback3Data1<U1> callback) {
+                dnfBuilder.clause(type1, callback);
+                return self();
+        }
+
+        public <U1, U2> T clause(Class<U1> type1, Class<U2> type2, ClauseCallback3Data2<U1, U2> callback) {
+                dnfBuilder.clause(type1, type2, callback);
+                return self();
+        }
+
+        public <U1, U2, U3> T clause(Class<U1> type1, Class<U2> type2, Class<U3> type3,
+                                                                 ClauseCallback3Data3<U1, U2, U3> callback) {
+                dnfBuilder.clause(type1, type2, type3, callback);
+                return self();
+        }
+
+        public T clause(ClauseCallback4Data0 callback) {
+                dnfBuilder.clause(callback);
+                return self();
+        }
+
+        public <U1> T clause(Class<U1> type1, ClauseCallback4Data1<U1> callback) {
+                dnfBuilder.clause(type1, callback);
+                return self();
+        }
+
+        public <U1, U2> T clause(Class<U1> type1, Class<U2> type2, ClauseCallback4Data2<U1, U2> callback) {
+                dnfBuilder.clause(type1, type2, callback);
+                return self();
+        }
+
+        public <U1, U2, U3> T clause(Class<U1> type1, Class<U2> type2, Class<U3> type3,
+                                                                 ClauseCallback4Data3<U1, U2, U3> callback) {
+                dnfBuilder.clause(type1, type2, type3, callback);
+                return self();
+        }
+
+        public <U1, U2, U3, U4> T clause(Class<U1> type1, Class<U2> type2, Class<U3> type3, Class<U4> type4,
+                                                                         ClauseCallback4Data4<U1, U2, U3, U4> callback) {
+                dnfBuilder.clause(type1, type2, type3, type4, callback);
+                return self();
+        }
+
+        public T clause(Literal... literals) {
+                dnfBuilder.clause(literals);
+                return self();
+        }
+
+        public T clause(Collection<? extends Literal> literals) {
+                dnfBuilder.clause(literals);
+                return self();
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/AnyQuery.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/AnyQuery.java
index d0a2367f..5e28af68 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/AnyQuery.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/AnyQuery.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.dnf;
 
 public sealed interface AnyQuery permits Query {
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/ClausePostProcessor.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/ClausePostProcessor.java
new file mode 100644
index 00000000..b5e7092b
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/ClausePostProcessor.java
@@ -0,0 +1,324 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf;
+
+import org.jetbrains.annotations.NotNull;
+import tools.refinery.store.query.literal.BooleanLiteral;
+import tools.refinery.store.query.literal.EquivalenceLiteral;
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.substitution.MapBasedSubstitution;
+import tools.refinery.store.query.substitution.StatelessSubstitution;
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.ParameterDirection;
+import tools.refinery.store.query.term.Variable;
+
+import java.util.*;
+import java.util.function.Function;
+
+class ClausePostProcessor {
+        private final Map<Variable, ParameterInfo> parameters;
+        private final List<Literal> literals;
+        private final Map<NodeVariable, NodeVariable> representatives = new LinkedHashMap<>();
+        private final Map<NodeVariable, Set<NodeVariable>> equivalencePartition = new HashMap<>();
+        private List<Literal> substitutedLiterals;
+        private final Set<Variable> existentiallyQuantifiedVariables = new LinkedHashSet<>();
+        private Set<Variable> positiveVariables;
+        private Map<Variable, Set<SortableLiteral>> variableToLiteralInputMap;
+        private PriorityQueue<SortableLiteral> literalsWithAllInputsBound;
+        private LinkedHashSet<Literal> topologicallySortedLiterals;
+
+        public ClausePostProcessor(Map<Variable, ParameterInfo> parameters, List<Literal> literals) {
+                this.parameters = parameters;
+                this.literals = literals;
+        }
+
+        public Result postProcessClause() {
+                mergeEquivalentNodeVariables();
+                substitutedLiterals = new ArrayList<>(literals.size());
+                keepParameterEquivalences();
+                substituteLiterals();
+                computeExistentiallyQuantifiedVariables();
+                computePositiveVariables();
+                validatePositiveRepresentatives();
+                validatePrivateVariables();
+                topologicallySortLiterals();
+                var filteredLiterals = new ArrayList<Literal>(topologicallySortedLiterals.size());
+                for (var literal : topologicallySortedLiterals) {
+                        var reducedLiteral = literal.reduce();
+                        if (BooleanLiteral.FALSE.equals(reducedLiteral)) {
+                                return ConstantResult.ALWAYS_FALSE;
+                        } else if (!BooleanLiteral.TRUE.equals(reducedLiteral)) {
+                                filteredLiterals.add(reducedLiteral);
+                        }
+                }
+                if (filteredLiterals.isEmpty()) {
+                        return ConstantResult.ALWAYS_TRUE;
+                }
+                var clause = new DnfClause(Collections.unmodifiableSet(positiveVariables),
+                                Collections.unmodifiableList(filteredLiterals));
+                return new ClauseResult(clause);
+        }
+
+        private void mergeEquivalentNodeVariables() {
+                for (var literal : literals) {
+                        if (isPositiveEquivalence(literal)) {
+                                var equivalenceLiteral = (EquivalenceLiteral) literal;
+                                mergeVariables(equivalenceLiteral.left(), equivalenceLiteral.right());
+                        }
+                }
+        }
+
+        private static boolean isPositiveEquivalence(Literal literal) {
+                return literal instanceof EquivalenceLiteral equivalenceLiteral && equivalenceLiteral.positive();
+        }
+
+        private void mergeVariables(NodeVariable left, NodeVariable right) {
+                var leftRepresentative = getRepresentative(left);
+                var rightRepresentative = getRepresentative(right);
+                var leftInfo = parameters.get(leftRepresentative);
+                var rightInfo = parameters.get(rightRepresentative);
+                if (leftInfo != null && (rightInfo == null || leftInfo.index() <= rightInfo.index())) {
+                        // Prefer the variable occurring earlier in the parameter list as a representative.
+                        doMergeVariables(leftRepresentative, rightRepresentative);
+                } else {
+                        doMergeVariables(rightRepresentative, leftRepresentative);
+                }
+        }
+
+        private void doMergeVariables(NodeVariable parentRepresentative, NodeVariable newChildRepresentative) {
+                var parentSet = getEquivalentVariables(parentRepresentative);
+                var childSet = getEquivalentVariables(newChildRepresentative);
+                parentSet.addAll(childSet);
+                equivalencePartition.remove(newChildRepresentative);
+                for (var childEquivalentNodeVariable : childSet) {
+                        representatives.put(childEquivalentNodeVariable, parentRepresentative);
+                }
+        }
+
+        private NodeVariable getRepresentative(NodeVariable variable) {
+                return representatives.computeIfAbsent(variable, Function.identity());
+        }
+
+        private Set<NodeVariable> getEquivalentVariables(NodeVariable variable) {
+                var representative = getRepresentative(variable);
+                if (!representative.equals(variable)) {
+                        throw new AssertionError("NodeVariable %s already has a representative %s"
+                                        .formatted(variable, representative));
+                }
+                return equivalencePartition.computeIfAbsent(variable, key -> {
+                        var set = new HashSet<NodeVariable>(1);
+                        set.add(key);
+                        return set;
+                });
+        }
+
+        private void keepParameterEquivalences() {
+                for (var pair : representatives.entrySet()) {
+                        var left = pair.getKey();
+                        var right = pair.getValue();
+                        if (!left.equals(right) && parameters.containsKey(left) && parameters.containsKey(right)) {
+                                substitutedLiterals.add(left.isEquivalent(right));
+                        }
+                }
+        }
+
+        private void substituteLiterals() {
+                Substitution substitution;
+                if (representatives.isEmpty()) {
+                        substitution = null;
+                } else {
+                        substitution = new MapBasedSubstitution(Collections.unmodifiableMap(representatives),
+                                        StatelessSubstitution.IDENTITY);
+                }
+                for (var literal : literals) {
+                        if (isPositiveEquivalence(literal)) {
+                                // We already retained all equivalences that cannot be replaced with substitutions in
+                                // {@link#keepParameterEquivalences()}.
+                                continue;
+                        }
+                        var substitutedLiteral = substitution == null ? literal : literal.substitute(substitution);
+                        substitutedLiterals.add(substitutedLiteral);
+                }
+        }
+
+        private void computeExistentiallyQuantifiedVariables() {
+                for (var literal : substitutedLiterals) {
+                        for (var variable : literal.getOutputVariables()) {
+                                boolean added = existentiallyQuantifiedVariables.add(variable);
+                                if (!variable.isUnifiable()) {
+                                        var parameterInfo = parameters.get(variable);
+                                        if (parameterInfo != null && parameterInfo.direction() == ParameterDirection.IN) {
+                                                throw new IllegalArgumentException("Trying to bind %s parameter %s"
+                                                                .formatted(ParameterDirection.IN, variable));
+                                        }
+                                        if (!added) {
+                                                throw new IllegalArgumentException("Variable %s has multiple assigned values"
+                                                                .formatted(variable));
+                                        }
+                                }
+                        }
+                }
+        }
+
+        private void computePositiveVariables() {
+                positiveVariables = new LinkedHashSet<>();
+                for (var pair : parameters.entrySet()) {
+                        var variable = pair.getKey();
+                        if (pair.getValue().direction() == ParameterDirection.IN) {
+                                // Inputs count as positive, because they are already bound when we evaluate literals.
+                                positiveVariables.add(variable);
+                        } else if (!existentiallyQuantifiedVariables.contains(variable)) {
+                                throw new IllegalArgumentException("Unbound %s parameter %s"
+                                                .formatted(ParameterDirection.OUT, variable));
+                        }
+                }
+                positiveVariables.addAll(existentiallyQuantifiedVariables);
+        }
+
+        private void validatePositiveRepresentatives() {
+                for (var pair : equivalencePartition.entrySet()) {
+                        var representative = pair.getKey();
+                        if (!positiveVariables.contains(representative)) {
+                                var variableSet = pair.getValue();
+                                throw new IllegalArgumentException("Variables %s were merged by equivalence but are not bound"
+                                                .formatted(variableSet));
+                        }
+                }
+        }
+
+        private void validatePrivateVariables() {
+                var negativeVariablesMap = new HashMap<Variable, Literal>();
+                for (var literal : substitutedLiterals) {
+                        for (var variable : literal.getPrivateVariables(positiveVariables)) {
+                                var oldLiteral = negativeVariablesMap.put(variable, literal);
+                                if (oldLiteral != null) {
+                                        throw new IllegalArgumentException("Unbound variable %s appears in multiple literals %s and %s"
+                                                        .formatted(variable, oldLiteral, literal));
+                                }
+                        }
+                }
+        }
+
+        private void topologicallySortLiterals() {
+                topologicallySortedLiterals = new LinkedHashSet<>(substitutedLiterals.size());
+                variableToLiteralInputMap = new HashMap<>();
+                literalsWithAllInputsBound = new PriorityQueue<>();
+                int size = substitutedLiterals.size();
+                for (int i = 0; i < size; i++) {
+                        var literal = substitutedLiterals.get(i);
+                        var sortableLiteral = new SortableLiteral(i, literal);
+                        sortableLiteral.enqueue();
+                }
+                while (!literalsWithAllInputsBound.isEmpty()) {
+                        var variable = literalsWithAllInputsBound.remove();
+                        variable.addToSortedLiterals();
+                }
+                if (!variableToLiteralInputMap.isEmpty()) {
+                        throw new IllegalArgumentException("Unbound input variables %s"
+                                        .formatted(variableToLiteralInputMap.keySet()));
+                }
+        }
+
+        private class SortableLiteral implements Comparable<SortableLiteral> {
+                private final int index;
+                private final Literal literal;
+                private final Set<Variable> remainingInputs;
+
+                private SortableLiteral(int index, Literal literal) {
+                        this.index = index;
+                        this.literal = literal;
+                        remainingInputs = new HashSet<>(literal.getInputVariables(positiveVariables));
+                        for (var pair : parameters.entrySet()) {
+                                if (pair.getValue().direction() == ParameterDirection.IN) {
+                                        remainingInputs.remove(pair.getKey());
+                                }
+                        }
+                }
+
+                public void enqueue() {
+                        if (allInputsBound()) {
+                                addToAllInputsBoundQueue();
+                        } else {
+                                addToVariableToLiteralInputMap();
+                        }
+                }
+
+                private void bindVariable(Variable input) {
+                        if (!remainingInputs.remove(input)) {
+                                throw new AssertionError("Already processed input %s of literal %s".formatted(input, literal));
+                        }
+                        if (allInputsBound()) {
+                                addToAllInputsBoundQueue();
+                        }
+                }
+
+                private boolean allInputsBound() {
+                        return remainingInputs.isEmpty();
+                }
+
+                private void addToVariableToLiteralInputMap() {
+                        for (var inputVariable : remainingInputs) {
+                                var literalSetForInput = variableToLiteralInputMap.computeIfAbsent(
+                                                inputVariable, key -> new HashSet<>());
+                                literalSetForInput.add(this);
+                        }
+                }
+
+                private void addToAllInputsBoundQueue() {
+                        literalsWithAllInputsBound.add(this);
+                }
+
+                public void addToSortedLiterals() {
+                        if (!allInputsBound()) {
+                                throw new AssertionError("Inputs %s of %s are not yet bound".formatted(remainingInputs, literal));
+                        }
+                        // Add literal if we haven't yet added a duplicate of this literal.
+                        topologicallySortedLiterals.add(literal);
+                        for (var variable : literal.getOutputVariables()) {
+                                var literalSetForInput = variableToLiteralInputMap.remove(variable);
+                                if (literalSetForInput == null) {
+                                        continue;
+                                }
+                                for (var targetSortableLiteral : literalSetForInput) {
+                                        targetSortableLiteral.bindVariable(variable);
+                                }
+                        }
+                }
+
+                @Override
+                public int compareTo(@NotNull ClausePostProcessor.SortableLiteral other) {
+                        return Integer.compare(index, other.index);
+                }
+
+                @Override
+                public boolean equals(Object o) {
+                        if (this == o) return true;
+                        if (o == null || getClass() != o.getClass()) return false;
+                        SortableLiteral that = (SortableLiteral) o;
+                        return index == that.index && Objects.equals(literal, that.literal);
+                }
+
+                @Override
+                public int hashCode() {
+                        return Objects.hash(index, literal);
+                }
+        }
+
+        public sealed interface Result permits ClauseResult, ConstantResult {
+        }
+
+        public record ClauseResult(DnfClause clause) implements Result {
+        }
+
+        public enum ConstantResult implements Result {
+                ALWAYS_TRUE,
+                ALWAYS_FALSE
+        }
+
+        public record ParameterInfo(ParameterDirection direction, int index) {
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/Dnf.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/Dnf.java
index 1b7759c7..c5b51b81 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/Dnf.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/Dnf.java
@@ -1,57 +1,61 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.dnf;
 
+import tools.refinery.store.query.Constraint;
+import tools.refinery.store.query.Reduction;
 import tools.refinery.store.query.equality.DnfEqualityChecker;
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
-import tools.refinery.store.query.Constraint;
-import tools.refinery.store.query.literal.LiteralReduction;
-import tools.refinery.store.query.term.Sort;
+import tools.refinery.store.query.term.Parameter;
 import tools.refinery.store.query.term.Variable;
 
 import java.util.Collection;
-import java.util.HashSet;
+import java.util.Collections;
 import java.util.List;
 import java.util.Set;
+import java.util.function.Consumer;
+import java.util.stream.Collectors;
 
 public final class Dnf implements Constraint {
         private static final String INDENTATION = "    ";
 
         private final String name;
-
         private final String uniqueName;
-
-        private final List<Variable> parameters;
-
+        private final List<SymbolicParameter> symbolicParameters;
         private final List<FunctionalDependency<Variable>> functionalDependencies;
-
         private final List<DnfClause> clauses;
 
-        Dnf(String name, List<Variable> parameters, List<FunctionalDependency<Variable>> functionalDependencies,
-                List<DnfClause> clauses) {
-                validateFunctionalDependencies(parameters, functionalDependencies);
+        Dnf(String name, List<SymbolicParameter> symbolicParameters,
+                List<FunctionalDependency<Variable>> functionalDependencies, List<DnfClause> clauses) {
+                validateFunctionalDependencies(symbolicParameters, functionalDependencies);
                 this.name = name;
                 this.uniqueName = DnfUtils.generateUniqueName(name);
-                this.parameters = parameters;
+                this.symbolicParameters = symbolicParameters;
                 this.functionalDependencies = functionalDependencies;
                 this.clauses = clauses;
         }
 
         private static void validateFunctionalDependencies(
-                        Collection<Variable> parameters, Collection<FunctionalDependency<Variable>> functionalDependencies) {
-                var parameterSet = new HashSet<>(parameters);
+                        Collection<SymbolicParameter> symbolicParameters,
+                        Collection<FunctionalDependency<Variable>> functionalDependencies) {
+                var parameterSet = symbolicParameters.stream().map(SymbolicParameter::getVariable).collect(Collectors.toSet());
                 for (var functionalDependency : functionalDependencies) {
-                        validateParameters(parameters, parameterSet, functionalDependency.forEach(), functionalDependency);
-                        validateParameters(parameters, parameterSet, functionalDependency.unique(), functionalDependency);
+                        validateParameters(symbolicParameters, parameterSet, functionalDependency.forEach(), functionalDependency);
+                        validateParameters(symbolicParameters, parameterSet, functionalDependency.unique(), functionalDependency);
                 }
         }
 
-        private static void validateParameters(Collection<Variable> parameters, Set<Variable> parameterSet,
-                                                                                   Collection<Variable> toValidate,
+        private static void validateParameters(Collection<SymbolicParameter> symbolicParameters,
+                                                                                   Set<Variable> parameterSet, Collection<Variable> toValidate,
                                                                                    FunctionalDependency<Variable> functionalDependency) {
                 for (var variable : toValidate) {
                         if (!parameterSet.contains(variable)) {
                                 throw new IllegalArgumentException(
                                                 "Variable %s of functional dependency %s does not appear in the parameter list %s"
-                                                                .formatted(variable, functionalDependency, parameters));
+                                                                .formatted(variable, functionalDependency, symbolicParameters));
                         }
                 }
         }
@@ -69,13 +73,12 @@ public final class Dnf implements Constraint {
                 return uniqueName;
         }
 
-        public List<Variable> getParameters() {
-                return parameters;
+        public List<SymbolicParameter> getSymbolicParameters() {
+                return symbolicParameters;
         }
 
-        @Override
-        public List<Sort> getSorts() {
-                return parameters.stream().map(Variable::getSort).toList();
+        public List<Parameter> getParameters() {
+                return Collections.unmodifiableList(symbolicParameters);
         }
 
         public List<FunctionalDependency<Variable>> getFunctionalDependencies() {
@@ -84,7 +87,7 @@ public final class Dnf implements Constraint {
 
         @Override
         public int arity() {
-                return parameters.size();
+                return symbolicParameters.size();
         }
 
         public List<DnfClause> getClauses() {
@@ -100,28 +103,34 @@ public final class Dnf implements Constraint {
         }
 
         @Override
-        public LiteralReduction getReduction() {
+        public Reduction getReduction() {
                 if (clauses.isEmpty()) {
-                        return LiteralReduction.ALWAYS_FALSE;
+                        return Reduction.ALWAYS_FALSE;
                 }
                 for (var clause : clauses) {
                         if (clause.literals().isEmpty()) {
-                                return LiteralReduction.ALWAYS_TRUE;
+                                return Reduction.ALWAYS_TRUE;
                         }
                 }
-                return LiteralReduction.NOT_REDUCIBLE;
+                return Reduction.NOT_REDUCIBLE;
         }
 
         public boolean equalsWithSubstitution(DnfEqualityChecker callEqualityChecker, Dnf other) {
                 if (arity() != other.arity()) {
                         return false;
                 }
+                for (int i = 0; i < arity(); i++) {
+                        if (!symbolicParameters.get(i).getDirection().equals(other.getSymbolicParameters().get(i).getDirection())) {
+                                return false;
+                        }
+                }
                 int numClauses = clauses.size();
                 if (numClauses != other.clauses.size()) {
                         return false;
                 }
                 for (int i = 0; i < numClauses; i++) {
-                        var literalEqualityHelper = new LiteralEqualityHelper(callEqualityChecker, parameters, other.parameters);
+                        var literalEqualityHelper = new LiteralEqualityHelper(callEqualityChecker, symbolicParameters,
+                                        other.symbolicParameters);
                         if (!clauses.get(i).equalsWithSubstitution(literalEqualityHelper, other.clauses.get(i))) {
                                 return false;
                         }
@@ -139,18 +148,18 @@ public final class Dnf implements Constraint {
 
         @Override
         public String toString() {
-                return "%s/%d".formatted(name, arity());
+                return "%s/%d".formatted(name(), arity());
         }
 
         @Override
         public String toReferenceString() {
-                return "@Dnf " + name;
+                return "@Dnf " + name();
         }
 
         public String toDefinitionString() {
                 var builder = new StringBuilder();
                 builder.append("pred ").append(name()).append("(");
-                var parameterIterator = parameters.iterator();
+                var parameterIterator = symbolicParameters.iterator();
                 if (parameterIterator.hasNext()) {
                         builder.append(parameterIterator.next());
                         while (parameterIterator.hasNext()) {
@@ -191,4 +200,14 @@ public final class Dnf implements Constraint {
         public static DnfBuilder builder(String name) {
                 return new DnfBuilder(name);
         }
+
+        public static Dnf of(Consumer<DnfBuilder> callback) {
+                return of(null, callback);
+        }
+
+        public static Dnf of(String name, Consumer<DnfBuilder> callback) {
+                var builder = builder(name);
+                callback.accept(builder);
+                return builder.build();
+        }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/DnfBuilder.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/DnfBuilder.java
index aad5a85f..8e38ca6b 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/DnfBuilder.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/DnfBuilder.java
@@ -1,7 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.dnf;
 
+import tools.refinery.store.query.dnf.callback.*;
 import tools.refinery.store.query.literal.Literal;
 import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.ParameterDirection;
 import tools.refinery.store.query.term.Variable;
 
 import java.util.*;
@@ -9,23 +17,57 @@ import java.util.*;
 @SuppressWarnings("UnusedReturnValue")
 public final class DnfBuilder {
         private final String name;
-
-        private final List<Variable> parameters = new ArrayList<>();
-
+        private final Set<Variable> parameterVariables = new LinkedHashSet<>();
+        private final List<SymbolicParameter> parameters = new ArrayList<>();
         private final List<FunctionalDependency<Variable>> functionalDependencies = new ArrayList<>();
-
         private final List<List<Literal>> clauses = new ArrayList<>();
 
         DnfBuilder(String name) {
                 this.name = name;
         }
 
+        public NodeVariable parameter() {
+                return parameter((String) null);
+        }
+
+        public NodeVariable parameter(String name) {
+                return parameter(name, ParameterDirection.OUT);
+        }
+
+        public NodeVariable parameter(ParameterDirection direction) {
+                return parameter((String) null, direction);
+        }
+
+        public NodeVariable parameter(String name, ParameterDirection direction) {
+                var variable = Variable.of(name);
+                parameter(variable, direction);
+                return variable;
+        }
+
+        public <T> DataVariable<T> parameter(Class<T> type) {
+                return parameter(null, type);
+        }
+
+        public <T> DataVariable<T> parameter(String name, Class<T> type) {
+                return parameter(name, type, ParameterDirection.OUT);
+        }
+
+        public <T> DataVariable<T> parameter(Class<T> type, ParameterDirection direction) {
+                return parameter(null, type, direction);
+        }
+
+        public <T> DataVariable<T> parameter(String name, Class<T> type, ParameterDirection direction) {
+                var variable = Variable.of(name, type);
+                parameter(variable, direction);
+                return variable;
+        }
+
         public DnfBuilder parameter(Variable variable) {
-                if (parameters.contains(variable)) {
-                        throw new IllegalArgumentException("Duplicate parameter: " + variable);
-                }
-                parameters.add(variable);
-                return this;
+                return parameter(variable, ParameterDirection.OUT);
+        }
+
+        public DnfBuilder parameter(Variable variable, ParameterDirection direction) {
+                return symbolicParameter(new SymbolicParameter(variable, direction));
         }
 
         public DnfBuilder parameters(Variable... variables) {
@@ -33,7 +75,34 @@ public final class DnfBuilder {
         }
 
         public DnfBuilder parameters(Collection<? extends Variable> variables) {
-                parameters.addAll(variables);
+                return parameters(variables, ParameterDirection.OUT);
+        }
+
+        public DnfBuilder parameters(Collection<? extends Variable> variables, ParameterDirection direction) {
+                for (var variable : variables) {
+                        parameter(variable, direction);
+                }
+                return this;
+        }
+
+        public DnfBuilder symbolicParameter(SymbolicParameter symbolicParameter) {
+                var variable = symbolicParameter.getVariable();
+                if (!parameterVariables.add(variable)) {
+                        throw new IllegalArgumentException("Variable %s is already on the parameter list %s"
+                                        .formatted(variable, parameters));
+                }
+                parameters.add(symbolicParameter);
+                return this;
+        }
+
+        public DnfBuilder symbolicParameters(SymbolicParameter... symbolicParameters) {
+                return symbolicParameters(List.of(symbolicParameters));
+        }
+
+        public DnfBuilder symbolicParameters(Collection<SymbolicParameter> symbolicParameters) {
+                for (var symbolicParameter : symbolicParameters) {
+                        symbolicParameter(symbolicParameter);
+                }
                 return this;
         }
 
@@ -51,33 +120,91 @@ public final class DnfBuilder {
                 return functionalDependency(new FunctionalDependency<>(Set.copyOf(forEach), Set.copyOf(unique)));
         }
 
+        public DnfBuilder clause(ClauseCallback0 callback) {
+                return clause(callback.toLiterals());
+        }
+
+        public DnfBuilder clause(ClauseCallback1Data0 callback) {
+                return clause(callback.toLiterals(Variable.of("v1")));
+        }
+
+        public <T> DnfBuilder clause(Class<T> type1, ClauseCallback1Data1<T> callback) {
+                return clause(callback.toLiterals(Variable.of("v1", type1)));
+        }
+
+        public DnfBuilder clause(ClauseCallback2Data0 callback) {
+                return clause(callback.toLiterals(Variable.of("v1"), Variable.of("v2")));
+        }
+
+        public <T> DnfBuilder clause(Class<T> type1, ClauseCallback2Data1<T> callback) {
+                return clause(callback.toLiterals(Variable.of("v1"), Variable.of("d1", type1)));
+        }
+
+        public <T1, T2> DnfBuilder clause(Class<T1> type1, Class<T2> type2, ClauseCallback2Data2<T1, T2> callback) {
+                return clause(callback.toLiterals(Variable.of("d1", type1), Variable.of("d2", type2)));
+        }
+
+        public DnfBuilder clause(ClauseCallback3Data0 callback) {
+                return clause(callback.toLiterals(Variable.of("v1"), Variable.of("v2"), Variable.of("v3")));
+        }
+
+        public <T> DnfBuilder clause(Class<T> type1, ClauseCallback3Data1<T> callback) {
+                return clause(callback.toLiterals(Variable.of("v1"), Variable.of("v2"), Variable.of("d1", type1)));
+        }
+
+        public <T1, T2> DnfBuilder clause(Class<T1> type1, Class<T2> type2, ClauseCallback3Data2<T1, T2> callback) {
+                return clause(callback.toLiterals(Variable.of("v1"), Variable.of("d1", type1), Variable.of("d2", type2)));
+        }
+
+        public <T1, T2, T3> DnfBuilder clause(Class<T1> type1, Class<T2> type2, Class<T3> type3,
+                                                                                  ClauseCallback3Data3<T1, T2, T3> callback) {
+                return clause(callback.toLiterals(Variable.of("d1", type1), Variable.of("d2", type2),
+                                Variable.of("d3", type3)));
+        }
+
+        public DnfBuilder clause(ClauseCallback4Data0 callback) {
+                return clause(callback.toLiterals(Variable.of("v1"), Variable.of("v2"), Variable.of("v3"), Variable.of("v4")));
+        }
+
+        public <T> DnfBuilder clause(Class<T> type1, ClauseCallback4Data1<T> callback) {
+                return clause(callback.toLiterals(Variable.of("v1"), Variable.of("v2"), Variable.of("v3"), Variable.of("d1",
+                                type1)));
+        }
+
+        public <T1, T2> DnfBuilder clause(Class<T1> type1, Class<T2> type2, ClauseCallback4Data2<T1, T2> callback) {
+                return clause(callback.toLiterals(Variable.of("v1"), Variable.of("v2"), Variable.of("d1", type1),
+                                Variable.of("d2", type2)));
+        }
+
+        public <T1, T2, T3> DnfBuilder clause(Class<T1> type1, Class<T2> type2, Class<T3> type3,
+                                                                                  ClauseCallback4Data3<T1, T2, T3> callback) {
+                return clause(callback.toLiterals(Variable.of("v1"), Variable.of("d1", type1), Variable.of("d2", type2),
+                                Variable.of("d3", type3)));
+        }
+
+        public <T1, T2, T3, T4> DnfBuilder clause(Class<T1> type1, Class<T2> type2, Class<T3> type3, Class<T4> type4,
+                                                                                          ClauseCallback4Data4<T1, T2, T3, T4> callback) {
+                return clause(callback.toLiterals(Variable.of("d1", type1), Variable.of("d2", type2),
+                                Variable.of("d3", type3), Variable.of("d4", type4)));
+        }
+
         public DnfBuilder clause(Literal... literals) {
                 clause(List.of(literals));
                 return this;
         }
 
         public DnfBuilder clause(Collection<? extends Literal> literals) {
-                // Remove duplicates by using a hashed data structure.
-                var filteredLiterals = new LinkedHashSet<Literal>(literals.size());
-                for (var literal : literals) {
-                        var reduction = literal.getReduction();
-                        switch (reduction) {
-                        case NOT_REDUCIBLE -> filteredLiterals.add(literal);
-                        case ALWAYS_TRUE -> {
-                                // Literals reducible to {@code true} can be omitted, because the model is always assumed to have at
-                                // least on object.
-                        }
-                        case ALWAYS_FALSE -> {
-                                // Clauses with {@code false} literals can be omitted entirely.
-                                return this;
-                        }
-                        default -> throw new IllegalArgumentException("Invalid reduction: " + reduction);
-                        }
-                }
-                clauses.add(List.copyOf(filteredLiterals));
+                clauses.add(List.copyOf(literals));
                 return this;
         }
 
+        <T> void output(DataVariable<T> outputVariable) {
+                // Copy parameter variables to exclude the newly added {@code outputVariable}.
+                var fromParameters = Set.copyOf(parameterVariables);
+                parameter(outputVariable, ParameterDirection.OUT);
+                functionalDependency(fromParameters, Set.of(outputVariable));
+        }
+
         public Dnf build() {
                 var postProcessedClauses = postProcessClauses();
                 return new Dnf(name, Collections.unmodifiableList(parameters),
@@ -85,26 +212,51 @@ public final class DnfBuilder {
                                 Collections.unmodifiableList(postProcessedClauses));
         }
 
-        <T> void output(DataVariable<T> outputVariable) {
-                functionalDependency(Set.copyOf(parameters), Set.of(outputVariable));
-                parameter(outputVariable);
-        }
-
         private List<DnfClause> postProcessClauses() {
+                var parameterInfoMap = getParameterInfoMap();
                 var postProcessedClauses = new ArrayList<DnfClause>(clauses.size());
                 for (var literals : clauses) {
-                        if (literals.isEmpty()) {
-                                // Predicate will always match, the other clauses are irrelevant.
-                                return List.of(new DnfClause(Set.of(), List.of()));
-                        }
-                        var variables = new HashSet<Variable>();
-                        for (var literal : literals) {
-                                variables.addAll(literal.getBoundVariables());
+                        var postProcessor = new ClausePostProcessor(parameterInfoMap, literals);
+                        var result = postProcessor.postProcessClause();
+                        if (result instanceof ClausePostProcessor.ClauseResult clauseResult) {
+                                postProcessedClauses.add(clauseResult.clause());
+                        } else if (result instanceof ClausePostProcessor.ConstantResult constantResult) {
+                                switch (constantResult) {
+                                case ALWAYS_TRUE -> {
+                                        var inputVariables = getInputVariables();
+                                        return List.of(new DnfClause(inputVariables, List.of()));
+                                }
+                                case ALWAYS_FALSE -> {
+                                        // Skip this clause because it can never match.
+                                }
+                                default -> throw new IllegalStateException("Unexpected ClausePostProcessor.ConstantResult: " +
+                                                constantResult);
+                                }
+                        } else {
+                                throw new IllegalStateException("Unexpected ClausePostProcessor.Result: " + result);
                         }
-                        parameters.forEach(variables::remove);
-                        postProcessedClauses.add(new DnfClause(Collections.unmodifiableSet(variables),
-                                        Collections.unmodifiableList(literals)));
                 }
                 return postProcessedClauses;
         }
+
+        private Map<Variable, ClausePostProcessor.ParameterInfo> getParameterInfoMap() {
+                var mutableParameterInfoMap = new LinkedHashMap<Variable, ClausePostProcessor.ParameterInfo>();
+                int arity = parameters.size();
+                for (int i = 0; i < arity; i++) {
+                        var parameter = parameters.get(i);
+                        mutableParameterInfoMap.put(parameter.getVariable(),
+                                        new ClausePostProcessor.ParameterInfo(parameter.getDirection(), i));
+                }
+                return Collections.unmodifiableMap(mutableParameterInfoMap);
+        }
+
+        private Set<Variable> getInputVariables() {
+                var inputParameters = new LinkedHashSet<Variable>();
+                for (var parameter : parameters) {
+                        if (parameter.getDirection() == ParameterDirection.IN) {
+                                inputParameters.add(parameter.getVariable());
+                        }
+                }
+                return Collections.unmodifiableSet(inputParameters);
+        }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/DnfClause.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/DnfClause.java
index 01830af1..fdd0d47c 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/DnfClause.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/DnfClause.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.dnf;
 
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
@@ -7,7 +12,7 @@ import tools.refinery.store.query.term.Variable;
 import java.util.List;
 import java.util.Set;
 
-public record DnfClause(Set<Variable> boundVariables, List<Literal> literals) {
+public record DnfClause(Set<Variable> positiveVariables, List<Literal> literals) {
         public boolean equalsWithSubstitution(LiteralEqualityHelper helper, DnfClause other) {
                 int size = literals.size();
                 if (size != other.literals.size()) {
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/DnfUtils.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/DnfUtils.java
index 9bcf944c..65ab3634 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/DnfUtils.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/DnfUtils.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.dnf;
 
 import java.util.UUID;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/FunctionalDependency.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/FunctionalDependency.java
index f4cd109f..b00b2cb7 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/FunctionalDependency.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/FunctionalDependency.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.dnf;
 
 import java.util.HashSet;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/FunctionalQuery.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/FunctionalQuery.java
index 5bf6f8c5..5a32b1ba 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/FunctionalQuery.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/FunctionalQuery.java
@@ -1,44 +1,47 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.dnf;
 
 import tools.refinery.store.query.literal.CallPolarity;
-import tools.refinery.store.query.term.*;
+import tools.refinery.store.query.term.Aggregator;
+import tools.refinery.store.query.term.AssignedValue;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.Variable;
 
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
 
-public final class FunctionalQuery<T> implements Query<T> {
-        private final Dnf dnf;
+public final class FunctionalQuery<T> extends Query<T> {
         private final Class<T> type;
 
         FunctionalQuery(Dnf dnf, Class<T> type) {
-                var parameters = dnf.getParameters();
+                super(dnf);
+                var parameters = dnf.getSymbolicParameters();
                 int outputIndex = dnf.arity() - 1;
                 for (int i = 0; i < outputIndex; i++) {
                         var parameter = parameters.get(i);
-                        if (!(parameter instanceof NodeVariable)) {
-                                throw new IllegalArgumentException("Expected parameter %s of %s to be of sort %s, but got %s instead"
-                                                .formatted(parameter, dnf, NodeSort.INSTANCE, parameter.getSort()));
+                        var parameterType = parameter.tryGetType();
+                        if (parameterType.isPresent()) {
+                                throw new IllegalArgumentException("Expected parameter %s of %s to be a node variable, got %s instead"
+                                                .formatted(parameter, dnf, parameterType.get().getName()));
                         }
                 }
                 var outputParameter = parameters.get(outputIndex);
-                if (!(outputParameter instanceof DataVariable<?> dataOutputParameter) ||
-                                !dataOutputParameter.getType().equals(type)) {
-                        throw new IllegalArgumentException("Expected parameter %s of %s to be of sort %s, but got %s instead"
-                                        .formatted(outputParameter, dnf, type, outputParameter.getSort()));
+                var outputParameterType = outputParameter.tryGetType();
+                if (outputParameterType.isEmpty() || !outputParameterType.get().equals(type)) {
+                        throw new IllegalArgumentException("Expected parameter %s of %s to be %s, but got %s instead".formatted(
+                                        outputParameter, dnf, type, outputParameterType.map(Class::getName).orElse("node")));
                 }
-                this.dnf = dnf;
                 this.type = type;
         }
 
         @Override
-        public String name() {
-                return dnf.name();
-        }
-
-        @Override
         public int arity() {
-                return dnf.arity() - 1;
+                return getDnf().arity() - 1;
         }
 
         @Override
@@ -51,17 +54,12 @@ public final class FunctionalQuery<T> implements Query<T> {
                 return null;
         }
 
-        @Override
-        public Dnf getDnf() {
-                return dnf;
-        }
-
         public AssignedValue<T> call(List<NodeVariable> arguments) {
                 return targetVariable -> {
                         var argumentsWithTarget = new ArrayList<Variable>(arguments.size() + 1);
                         argumentsWithTarget.addAll(arguments);
                         argumentsWithTarget.add(targetVariable);
-                        return dnf.call(CallPolarity.POSITIVE, argumentsWithTarget);
+                        return getDnf().call(CallPolarity.POSITIVE, argumentsWithTarget);
                 };
         }
 
@@ -75,7 +73,9 @@ public final class FunctionalQuery<T> implements Query<T> {
                         var argumentsWithPlaceholder = new ArrayList<Variable>(arguments.size() + 1);
                         argumentsWithPlaceholder.addAll(arguments);
                         argumentsWithPlaceholder.add(placeholderVariable);
-                        return dnf.aggregate(placeholderVariable, aggregator, argumentsWithPlaceholder).toLiteral(targetVariable);
+                        return getDnf()
+                                        .aggregateBy(placeholderVariable, aggregator, argumentsWithPlaceholder)
+                                        .toLiteral(targetVariable);
                 };
         }
 
@@ -87,17 +87,13 @@ public final class FunctionalQuery<T> implements Query<T> {
         public boolean equals(Object o) {
                 if (this == o) return true;
                 if (o == null || getClass() != o.getClass()) return false;
+                if (!super.equals(o)) return false;
                 FunctionalQuery<?> that = (FunctionalQuery<?>) o;
-                return dnf.equals(that.dnf) && type.equals(that.type);
+                return Objects.equals(type, that.type);
         }
 
         @Override
         public int hashCode() {
-                return Objects.hash(dnf, type);
-        }
-
-        @Override
-        public String toString() {
-                return dnf.toString();
+                return Objects.hash(super.hashCode(), type);
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/FunctionalQueryBuilder.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/FunctionalQueryBuilder.java
index ca2bc006..d1cd7ba8 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/FunctionalQueryBuilder.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/FunctionalQueryBuilder.java
@@ -1,46 +1,29 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.dnf;
 
-import tools.refinery.store.query.literal.Literal;
-import tools.refinery.store.query.term.Variable;
+import tools.refinery.store.query.term.DataVariable;
 
-import java.util.Collection;
-import java.util.Set;
-
-public final class FunctionalQueryBuilder<T> {
-        private final DnfBuilder dnfBuilder;
+public final class FunctionalQueryBuilder<T> extends AbstractQueryBuilder<FunctionalQueryBuilder<T>> {
+        private final DataVariable<T> outputVariable;
         private final Class<T> type;
 
-        FunctionalQueryBuilder(DnfBuilder dnfBuilder, Class<T> type) {
-                this.dnfBuilder = dnfBuilder;
+        FunctionalQueryBuilder(DataVariable<T> outputVariable, DnfBuilder dnfBuilder, Class<T> type) {
+                super(dnfBuilder);
+                this.outputVariable = outputVariable;
                 this.type = type;
         }
 
-        public FunctionalQueryBuilder<T> functionalDependencies(Collection<FunctionalDependency<Variable>> functionalDependencies) {
-                dnfBuilder.functionalDependencies(functionalDependencies);
-                return this;
-        }
-
-        public FunctionalQueryBuilder<T> functionalDependency(FunctionalDependency<Variable> functionalDependency) {
-                dnfBuilder.functionalDependency(functionalDependency);
-                return this;
-        }
-
-        public FunctionalQueryBuilder<T> functionalDependency(Set<? extends Variable> forEach, Set<? extends Variable> unique) {
-                dnfBuilder.functionalDependency(forEach, unique);
-                return this;
-        }
-
-        public FunctionalQueryBuilder<T> clause(Literal... literals) {
-                dnfBuilder.clause(literals);
-                return this;
-        }
-
-        public FunctionalQueryBuilder<T> clause(Collection<? extends Literal> literals) {
-                dnfBuilder.clause(literals);
+        @Override
+        protected FunctionalQueryBuilder<T> self() {
                 return this;
         }
 
         public FunctionalQuery<T> build() {
+                dnfBuilder.output(outputVariable);
                 return dnfBuilder.build().asFunction(type);
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/Query.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/Query.java
index 32e33052..aaa52ce6 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/Query.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/Query.java
@@ -1,16 +1,179 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.dnf;
 
-public sealed interface Query<T> extends AnyQuery permits RelationalQuery, FunctionalQuery {
+import tools.refinery.store.query.dnf.callback.*;
+import tools.refinery.store.query.term.ParameterDirection;
+import tools.refinery.store.query.term.Variable;
+
+import java.util.Objects;
+
+public abstract sealed class Query<T> implements AnyQuery permits FunctionalQuery, RelationalQuery {
+        private static final String OUTPUT_VARIABLE_NAME = "output";
+
+        private final Dnf dnf;
+
+        protected Query(Dnf dnf) {
+                for (var parameter : dnf.getSymbolicParameters()) {
+                        if (parameter.getDirection() != ParameterDirection.OUT) {
+                                throw new IllegalArgumentException("Query parameter %s with direction %s is not allowed"
+                                                .formatted(parameter.getVariable(), parameter.getDirection()));
+                        }
+                }
+                this.dnf = dnf;
+        }
+
+        @Override
+        public String name() {
+                return dnf.name();
+        }
+
+        @Override
+        public Dnf getDnf() {
+                return dnf;
+        }
+
+        // Allow redeclaration of the method with refined return type.
+        @SuppressWarnings("squid:S3038")
         @Override
-        Class<T> valueType();
+        public abstract Class<T> valueType();
 
-        T defaultValue();
+        public abstract T defaultValue();
 
-        static QueryBuilder builder() {
-                return new QueryBuilder();
+        @Override
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                Query<?> that = (Query<?>) o;
+                return Objects.equals(dnf, that.dnf);
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(dnf);
         }
 
-        static QueryBuilder builder(String name) {
+        @Override
+        public String toString() {
+                return dnf.toString();
+        }
+
+        public static QueryBuilder builder() {
+                return builder(null);
+        }
+
+        public static QueryBuilder builder(String name) {
                 return new QueryBuilder(name);
         }
+
+        public static RelationalQuery of(QueryCallback0 callback) {
+                return of(null, callback);
+        }
+
+        public static RelationalQuery of(String name, QueryCallback0 callback) {
+                var builder = builder(name);
+                callback.accept(builder);
+                return builder.build();
+        }
+
+        public static RelationalQuery of(QueryCallback1 callback) {
+                return of(null, callback);
+        }
+
+        public static RelationalQuery of(String name, QueryCallback1 callback) {
+                var builder = builder(name);
+                callback.accept(builder, builder.parameter("p1"));
+                return builder.build();
+        }
+
+        public static RelationalQuery of(QueryCallback2 callback) {
+                return of(null, callback);
+        }
+
+        public static RelationalQuery of(String name, QueryCallback2 callback) {
+                var builder = builder(name);
+                callback.accept(builder, builder.parameter("p1"), builder.parameter("p2"));
+                return builder.build();
+        }
+
+        public static RelationalQuery of(QueryCallback3 callback) {
+                return of(null, callback);
+        }
+
+        public static RelationalQuery of(String name, QueryCallback3 callback) {
+                var builder = builder(name);
+                callback.accept(builder, builder.parameter("p1"), builder.parameter("p2"), builder.parameter("p3"));
+                return builder.build();
+        }
+
+        public static RelationalQuery of(QueryCallback4 callback) {
+                return of(null, callback);
+        }
+
+        public static RelationalQuery of(String name, QueryCallback4 callback) {
+                var builder = builder(name);
+                callback.accept(builder, builder.parameter("p1"), builder.parameter("p2"), builder.parameter("p3"),
+                                builder.parameter("p4"));
+                return builder.build();
+        }
+
+        public static <T> FunctionalQuery<T> of(Class<T> type, FunctionalQueryCallback0<T> callback) {
+                return of(null, type, callback);
+        }
+
+        public static <T> FunctionalQuery<T> of(String name, Class<T> type, FunctionalQueryCallback0<T> callback) {
+                var outputVariable = Variable.of(OUTPUT_VARIABLE_NAME, type);
+                var builder = builder(name).output(outputVariable);
+                callback.accept(builder, outputVariable);
+                return builder.build();
+        }
+
+        public static <T> FunctionalQuery<T> of(Class<T> type, FunctionalQueryCallback1<T> callback) {
+                return of(null, type, callback);
+        }
+
+        public static <T> FunctionalQuery<T> of(String name, Class<T> type, FunctionalQueryCallback1<T> callback) {
+                var outputVariable = Variable.of(OUTPUT_VARIABLE_NAME, type);
+                var builder = builder(name).output(outputVariable);
+                callback.accept(builder, builder.parameter("p1"), outputVariable);
+                return builder.build();
+        }
+
+        public static <T> FunctionalQuery<T> of(Class<T> type, FunctionalQueryCallback2<T> callback) {
+                return of(null, type, callback);
+        }
+
+        public static <T> FunctionalQuery<T> of(String name, Class<T> type, FunctionalQueryCallback2<T> callback) {
+                var outputVariable = Variable.of(OUTPUT_VARIABLE_NAME, type);
+                var builder = builder(name).output(outputVariable);
+                callback.accept(builder, builder.parameter("p1"), builder.parameter("p2"), outputVariable);
+                return builder.build();
+        }
+
+        public static <T> FunctionalQuery<T> of(Class<T> type, FunctionalQueryCallback3<T> callback) {
+                return of(null, type, callback);
+        }
+
+        public static <T> FunctionalQuery<T> of(String name, Class<T> type, FunctionalQueryCallback3<T> callback) {
+                var outputVariable = Variable.of(OUTPUT_VARIABLE_NAME, type);
+                var builder = builder(name).output(outputVariable);
+                callback.accept(builder, builder.parameter("p1"), builder.parameter("p2"), builder.parameter("p3"),
+                                outputVariable);
+                return builder.build();
+        }
+
+        public static <T> FunctionalQuery<T> of(Class<T> type, FunctionalQueryCallback4<T> callback) {
+                return of(null, type, callback);
+        }
+
+        public static <T> FunctionalQuery<T> of(String name, Class<T> type, FunctionalQueryCallback4<T> callback) {
+                var outputVariable = Variable.of(OUTPUT_VARIABLE_NAME, type);
+                var builder = builder(name).output(outputVariable);
+                callback.accept(builder, builder.parameter("p1"), builder.parameter("p2"), builder.parameter("p3"),
+                                builder.parameter("p4"), outputVariable);
+                return builder.build();
+        }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/QueryBuilder.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/QueryBuilder.java
index ed253cc9..138911bc 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/QueryBuilder.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/QueryBuilder.java
@@ -1,68 +1,24 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.dnf;
 
-import tools.refinery.store.query.literal.Literal;
 import tools.refinery.store.query.term.DataVariable;
-import tools.refinery.store.query.term.NodeVariable;
-import tools.refinery.store.query.term.Variable;
-
-import java.util.Collection;
-import java.util.List;
-import java.util.Set;
-
-public final class QueryBuilder {
-        private final DnfBuilder dnfBuilder;
 
+public final class QueryBuilder extends AbstractQueryBuilder<QueryBuilder> {
         QueryBuilder(String name) {
-                dnfBuilder = Dnf.builder(name);
-        }
-
-        QueryBuilder() {
-                dnfBuilder = Dnf.builder();
-        }
-
-        public QueryBuilder parameter(NodeVariable variable) {
-                dnfBuilder.parameter(variable);
-                return this;
+                super(Dnf.builder(name));
         }
 
-        public QueryBuilder parameters(NodeVariable... variables) {
-                dnfBuilder.parameters(variables);
-                return this;
-        }
-
-        public QueryBuilder parameters(List<NodeVariable> variables) {
-                dnfBuilder.parameters(variables);
+        @Override
+        protected QueryBuilder self() {
                 return this;
         }
 
         public <T> FunctionalQueryBuilder<T> output(DataVariable<T> outputVariable) {
-                dnfBuilder.output(outputVariable);
-                return new FunctionalQueryBuilder<>(dnfBuilder, outputVariable.getType());
-        }
-
-        public QueryBuilder functionalDependencies(Collection<FunctionalDependency<Variable>> functionalDependencies) {
-                dnfBuilder.functionalDependencies(functionalDependencies);
-                return this;
-        }
-
-        public QueryBuilder functionalDependency(FunctionalDependency<Variable> functionalDependency) {
-                dnfBuilder.functionalDependency(functionalDependency);
-                return this;
-        }
-
-        public QueryBuilder functionalDependency(Set<? extends Variable> forEach, Set<? extends Variable> unique) {
-                dnfBuilder.functionalDependency(forEach, unique);
-                return this;
-        }
-
-        public QueryBuilder clause(Literal... literals) {
-                dnfBuilder.clause(literals);
-                return this;
-        }
-
-        public QueryBuilder clause(Collection<? extends Literal> literals) {
-                dnfBuilder.clause(literals);
-                return this;
+                return new FunctionalQueryBuilder<>(outputVariable, dnfBuilder, outputVariable.getType());
         }
 
         public RelationalQuery build() {
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/RelationalQuery.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/RelationalQuery.java
index 5307e509..d34a7ace 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/RelationalQuery.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/RelationalQuery.java
@@ -1,36 +1,33 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.dnf;
 
 import tools.refinery.store.query.literal.CallLiteral;
 import tools.refinery.store.query.literal.CallPolarity;
 import tools.refinery.store.query.term.AssignedValue;
-import tools.refinery.store.query.term.NodeSort;
 import tools.refinery.store.query.term.NodeVariable;
 
 import java.util.Collections;
 import java.util.List;
-import java.util.Objects;
-
-public final class RelationalQuery implements Query<Boolean> {
-        private final Dnf dnf;
 
+public final class RelationalQuery extends Query<Boolean> {
         RelationalQuery(Dnf dnf) {
-                for (var parameter : dnf.getParameters()) {
-                        if (!(parameter instanceof NodeVariable)) {
-                                throw new IllegalArgumentException("Expected parameter %s of %s to be of sort %s, but got %s instead"
-                                                .formatted(parameter, dnf, NodeSort.INSTANCE, parameter.getSort()));
+                super(dnf);
+                for (var parameter : dnf.getSymbolicParameters()) {
+                        var parameterType = parameter.tryGetType();
+                        if (parameterType.isPresent()) {
+                                throw new IllegalArgumentException("Expected parameter %s of %s to be a node variable, got %s instead"
+                                                .formatted(parameter, dnf, parameterType.get().getName()));
                         }
                 }
-                this.dnf = dnf;
-        }
-
-        @Override
-        public String name() {
-                return dnf.name();
         }
 
         @Override
         public int arity() {
-                return dnf.arity();
+                return getDnf().arity();
         }
 
         @Override
@@ -43,51 +40,27 @@ public final class RelationalQuery implements Query<Boolean> {
                 return false;
         }
 
-        @Override
-        public Dnf getDnf() {
-                return dnf;
-        }
-
         public CallLiteral call(CallPolarity polarity, List<NodeVariable> arguments) {
-                return dnf.call(polarity, Collections.unmodifiableList(arguments));
+                return getDnf().call(polarity, Collections.unmodifiableList(arguments));
         }
 
         public CallLiteral call(CallPolarity polarity, NodeVariable... arguments) {
-                return dnf.call(polarity, arguments);
+                return getDnf().call(polarity, arguments);
         }
 
         public CallLiteral call(NodeVariable... arguments) {
-                return dnf.call(arguments);
+                return getDnf().call(arguments);
         }
 
         public CallLiteral callTransitive(NodeVariable left, NodeVariable right) {
-                return dnf.callTransitive(left, right);
+                return getDnf().callTransitive(left, right);
         }
 
         public AssignedValue<Integer> count(List<NodeVariable> arguments) {
-                return dnf.count(Collections.unmodifiableList(arguments));
+                return getDnf().count(Collections.unmodifiableList(arguments));
         }
 
         public AssignedValue<Integer> count(NodeVariable... arguments) {
-                return dnf.count(arguments);
-        }
-
-
-        @Override
-        public boolean equals(Object o) {
-                if (this == o) return true;
-                if (o == null || getClass() != o.getClass()) return false;
-                RelationalQuery that = (RelationalQuery) o;
-                return dnf.equals(that.dnf);
-        }
-
-        @Override
-        public int hashCode() {
-                return Objects.hash(dnf);
-        }
-
-        @Override
-        public String toString() {
-                return dnf.toString();
+                return getDnf().count(arguments);
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/SymbolicParameter.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/SymbolicParameter.java
new file mode 100644
index 00000000..e0d3ba1f
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/SymbolicParameter.java
@@ -0,0 +1,52 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf;
+
+import tools.refinery.store.query.term.Parameter;
+import tools.refinery.store.query.term.ParameterDirection;
+import tools.refinery.store.query.term.Variable;
+
+import java.util.Objects;
+
+public final class SymbolicParameter extends Parameter {
+        private final Variable variable;
+
+        public SymbolicParameter(Variable variable, ParameterDirection direction) {
+                super(variable.tryGetType().orElse(null), direction);
+                this.variable = variable;
+        }
+
+        public Variable getVariable() {
+                return variable;
+        }
+
+        public boolean isUnifiable() {
+                return variable.isUnifiable();
+        }
+
+        @Override
+        public String toString() {
+                var direction = getDirection();
+                if (direction == ParameterDirection.OUT) {
+                        return variable.toString();
+                }
+                return "%s %s".formatted(getDirection(), variable);
+        }
+
+        @Override
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                if (!super.equals(o)) return false;
+                SymbolicParameter that = (SymbolicParameter) o;
+                return Objects.equals(variable, that.variable);
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(super.hashCode(), variable);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback0.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback0.java
new file mode 100644
index 00000000..d98dda2e
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback0.java
@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback0 {
+        Collection<Literal> toLiterals();
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback1Data0.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback1Data0.java
new file mode 100644
index 00000000..4c01a527
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback1Data0.java
@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.NodeVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback1Data0 {
+        Collection<Literal> toLiterals(NodeVariable v1);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback1Data1.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback1Data1.java
new file mode 100644
index 00000000..2c0cb6eb
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback1Data1.java
@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.DataVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback1Data1<T> {
+        Collection<Literal> toLiterals(DataVariable<T> d1);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback2Data0.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback2Data0.java
new file mode 100644
index 00000000..d764bdba
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback2Data0.java
@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.NodeVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback2Data0 {
+        Collection<Literal> toLiterals(NodeVariable v1, NodeVariable v2);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback2Data1.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback2Data1.java
new file mode 100644
index 00000000..140af03a
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback2Data1.java
@@ -0,0 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback2Data1<T> {
+        Collection<Literal> toLiterals(NodeVariable v1, DataVariable<T> x1);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback2Data2.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback2Data2.java
new file mode 100644
index 00000000..bfc8637c
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback2Data2.java
@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.DataVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback2Data2<T1, T2> {
+        Collection<Literal> toLiterals(DataVariable<T1> x1, DataVariable<T2> x2);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback3Data0.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback3Data0.java
new file mode 100644
index 00000000..074df65b
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback3Data0.java
@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.NodeVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback3Data0 {
+        Collection<Literal> toLiterals(NodeVariable v1, NodeVariable v2, NodeVariable v3);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback3Data1.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback3Data1.java
new file mode 100644
index 00000000..24ba5187
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback3Data1.java
@@ -0,0 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback3Data1<T> {
+        Collection<Literal> toLiterals(NodeVariable v1, NodeVariable v2, DataVariable<T> d1);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback3Data2.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback3Data2.java
new file mode 100644
index 00000000..2a2e837a
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback3Data2.java
@@ -0,0 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback3Data2<T1, T2> {
+        Collection<Literal> toLiterals(NodeVariable v1, DataVariable<T1> d1, DataVariable<T2> d2);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback3Data3.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback3Data3.java
new file mode 100644
index 00000000..8f4bdd01
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback3Data3.java
@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.DataVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback3Data3<T1, T2, T3> {
+        Collection<Literal> toLiterals(DataVariable<T1> d1, DataVariable<T2> d2, DataVariable<T3> d3);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data0.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data0.java
new file mode 100644
index 00000000..ed0f87b2
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data0.java
@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.NodeVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback4Data0 {
+        Collection<Literal> toLiterals(NodeVariable v1, NodeVariable v2, NodeVariable v3, NodeVariable v4);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data1.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data1.java
new file mode 100644
index 00000000..9b27e2e1
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data1.java
@@ -0,0 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback4Data1<T> {
+        Collection<Literal> toLiterals(NodeVariable v1, NodeVariable v2, NodeVariable v3, DataVariable<T> d1);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data2.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data2.java
new file mode 100644
index 00000000..cbc4808e
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data2.java
@@ -0,0 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback4Data2<T1, T2> {
+        Collection<Literal> toLiterals(NodeVariable v1, NodeVariable v2, DataVariable<T1> d1, DataVariable<T2> d2);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data3.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data3.java
new file mode 100644
index 00000000..a6258f36
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data3.java
@@ -0,0 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback4Data3<T1, T2, T3> {
+        Collection<Literal> toLiterals(NodeVariable v1, DataVariable<T1> d1, DataVariable<T2> d2, DataVariable<T3> d3);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data4.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data4.java
new file mode 100644
index 00000000..b52a911a
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/ClauseCallback4Data4.java
@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.DataVariable;
+
+import java.util.Collection;
+
+@FunctionalInterface
+public interface ClauseCallback4Data4<T1, T2, T3, T4> {
+        Collection<Literal> toLiterals(DataVariable<T1> d1, DataVariable<T2> d2, DataVariable<T3> d3, DataVariable<T4> d4);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback0.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback0.java
new file mode 100644
index 00000000..63b3eee6
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback0.java
@@ -0,0 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.dnf.FunctionalQueryBuilder;
+import tools.refinery.store.query.term.DataVariable;
+
+@FunctionalInterface
+public interface FunctionalQueryCallback0<T> {
+        void accept(FunctionalQueryBuilder<T> builder, DataVariable<T> output);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback1.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback1.java
new file mode 100644
index 00000000..1295a118
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback1.java
@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.dnf.FunctionalQueryBuilder;
+import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+
+@FunctionalInterface
+public interface FunctionalQueryCallback1<T> {
+        void accept(FunctionalQueryBuilder<T> builder, NodeVariable p1, DataVariable<T> output);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback2.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback2.java
new file mode 100644
index 00000000..d5b7f9ff
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback2.java
@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.dnf.FunctionalQueryBuilder;
+import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+
+@FunctionalInterface
+public interface FunctionalQueryCallback2<T> {
+        void accept(FunctionalQueryBuilder<T> builder, NodeVariable p1, NodeVariable p2, DataVariable<T> output);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback3.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback3.java
new file mode 100644
index 00000000..dc8404a0
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback3.java
@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.dnf.FunctionalQueryBuilder;
+import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+
+@FunctionalInterface
+public interface FunctionalQueryCallback3<T> {
+        void accept(FunctionalQueryBuilder<T> builder, NodeVariable p1, NodeVariable p2, NodeVariable p3,
+                                DataVariable<T> output);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback4.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback4.java
new file mode 100644
index 00000000..b6d3ddb0
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/FunctionalQueryCallback4.java
@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.dnf.FunctionalQueryBuilder;
+import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+
+@FunctionalInterface
+public interface FunctionalQueryCallback4<T> {
+        void accept(FunctionalQueryBuilder<T> builder, NodeVariable p1, NodeVariable p2, NodeVariable p3, NodeVariable p4,
+                                DataVariable<T> output);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback0.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback0.java
new file mode 100644
index 00000000..3cf1de48
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback0.java
@@ -0,0 +1,13 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.dnf.QueryBuilder;
+
+@FunctionalInterface
+public interface QueryCallback0 {
+        void accept(QueryBuilder builder);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback1.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback1.java
new file mode 100644
index 00000000..0a150955
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback1.java
@@ -0,0 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.dnf.QueryBuilder;
+import tools.refinery.store.query.term.NodeVariable;
+
+@FunctionalInterface
+public interface QueryCallback1 {
+        void accept(QueryBuilder builder, NodeVariable p1);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback2.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback2.java
new file mode 100644
index 00000000..9493a7b4
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback2.java
@@ -0,0 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.dnf.QueryBuilder;
+import tools.refinery.store.query.term.NodeVariable;
+
+@FunctionalInterface
+public interface QueryCallback2 {
+        void accept(QueryBuilder builder, NodeVariable p1, NodeVariable p2);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback3.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback3.java
new file mode 100644
index 00000000..358c7da7
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback3.java
@@ -0,0 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.dnf.QueryBuilder;
+import tools.refinery.store.query.term.NodeVariable;
+
+@FunctionalInterface
+public interface QueryCallback3 {
+        void accept(QueryBuilder builder, NodeVariable p1, NodeVariable p2, NodeVariable p3);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback4.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback4.java
new file mode 100644
index 00000000..890dda16
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/dnf/callback/QueryCallback4.java
@@ -0,0 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf.callback;
+
+import tools.refinery.store.query.dnf.QueryBuilder;
+import tools.refinery.store.query.term.NodeVariable;
+
+@FunctionalInterface
+public interface QueryCallback4 {
+        void accept(QueryBuilder builder, NodeVariable p1, NodeVariable p2, NodeVariable p3, NodeVariable p4);
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/equality/DeepDnfEqualityChecker.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/equality/DeepDnfEqualityChecker.java
index c3bc3ea3..1eeb5723 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/equality/DeepDnfEqualityChecker.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/equality/DeepDnfEqualityChecker.java
@@ -1,6 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.equality;
 
 import tools.refinery.store.query.dnf.Dnf;
+import tools.refinery.store.query.dnf.DnfClause;
+import tools.refinery.store.query.dnf.SymbolicParameter;
+import tools.refinery.store.query.literal.Literal;
 import tools.refinery.store.util.CycleDetectingMapper;
 
 import java.util.List;
@@ -14,6 +22,45 @@ public class DeepDnfEqualityChecker implements DnfEqualityChecker {
                 return mapper.map(new Pair(left, right));
         }
 
+        public boolean dnfEqualRaw(List<SymbolicParameter> symbolicParameters,
+                                                           List<? extends List<? extends Literal>> clauses, Dnf other) {
+                int arity = symbolicParameters.size();
+                if (arity != other.arity()) {
+                        return false;
+                }
+                for (int i = 0; i < arity; i++) {
+                        if (!symbolicParameters.get(i).getDirection().equals(other.getSymbolicParameters().get(i).getDirection())) {
+                                return false;
+                        }
+                }
+                int numClauses = clauses.size();
+                if (numClauses != other.getClauses().size()) {
+                        return false;
+                }
+                for (int i = 0; i < numClauses; i++) {
+                        var literalEqualityHelper = new LiteralEqualityHelper(this, symbolicParameters,
+                                        other.getSymbolicParameters());
+                        if (!equalsWithSubstitutionRaw(literalEqualityHelper, clauses.get(i), other.getClauses().get(i))) {
+                                return false;
+                        }
+                }
+                return true;
+        }
+
+        private boolean equalsWithSubstitutionRaw(LiteralEqualityHelper helper, List<? extends Literal> literals,
+                                                                                          DnfClause other) {
+                int size = literals.size();
+                if (size != other.literals().size()) {
+                        return false;
+                }
+                for (int i = 0; i < size; i++) {
+                        if (!literals.get(i).equalsWithSubstitution(helper, other.literals().get(i))) {
+                                return false;
+                        }
+                }
+                return true;
+        }
+
         protected boolean doCheckEqual(Pair pair) {
                 return pair.left.equalsWithSubstitution(this, pair.right);
         }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/equality/DnfEqualityChecker.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/equality/DnfEqualityChecker.java
index 6b1f2076..4a8bee3b 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/equality/DnfEqualityChecker.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/equality/DnfEqualityChecker.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.equality;
 
 import tools.refinery.store.query.dnf.Dnf;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/equality/LiteralEqualityHelper.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/equality/LiteralEqualityHelper.java
index 07d261ea..9315fb30 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/equality/LiteralEqualityHelper.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/equality/LiteralEqualityHelper.java
@@ -1,6 +1,12 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.equality;
 
 import tools.refinery.store.query.dnf.Dnf;
+import tools.refinery.store.query.dnf.SymbolicParameter;
 import tools.refinery.store.query.term.Variable;
 
 import java.util.HashMap;
@@ -12,8 +18,8 @@ public class LiteralEqualityHelper {
         private final Map<Variable, Variable> leftToRight;
         private final Map<Variable, Variable> rightToLeft;
 
-        public LiteralEqualityHelper(DnfEqualityChecker dnfEqualityChecker, List<Variable> leftParameters,
-                                                                 List<Variable> rightParameters) {
+        public LiteralEqualityHelper(DnfEqualityChecker dnfEqualityChecker, List<SymbolicParameter> leftParameters,
+                                                                 List<SymbolicParameter> rightParameters) {
                 this.dnfEqualityChecker = dnfEqualityChecker;
                 var arity = leftParameters.size();
                 if (arity != rightParameters.size()) {
@@ -22,7 +28,7 @@ public class LiteralEqualityHelper {
                 leftToRight = new HashMap<>(arity);
                 rightToLeft = new HashMap<>(arity);
                 for (int i = 0; i < arity; i++) {
-                        if (!variableEqual(leftParameters.get(i), rightParameters.get(i))) {
+                        if (!variableEqual(leftParameters.get(i).getVariable(), rightParameters.get(i).getVariable())) {
                                 throw new IllegalArgumentException("Parameter lists cannot be unified: duplicate parameter " + i);
                         }
                 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AbstractCallLiteral.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AbstractCallLiteral.java
index 657ca26b..8ef8e8b4 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AbstractCallLiteral.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AbstractCallLiteral.java
@@ -1,17 +1,26 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
 import tools.refinery.store.query.Constraint;
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
 import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.ParameterDirection;
 import tools.refinery.store.query.term.Variable;
 
-import java.util.List;
-import java.util.Objects;
+import java.util.*;
 
 public abstract class AbstractCallLiteral implements Literal {
         private final Constraint target;
         private final List<Variable> arguments;
+        private final Set<Variable> inArguments;
+        private final Set<Variable> outArguments;
 
+        // Use exhaustive switch over enums.
+        @SuppressWarnings("squid:S1301")
         protected AbstractCallLiteral(Constraint target, List<Variable> arguments) {
                 int arity = target.arity();
                 if (arguments.size() != arity) {
@@ -20,14 +29,46 @@ public abstract class AbstractCallLiteral implements Literal {
                 }
                 this.target = target;
                 this.arguments = arguments;
-                var sorts = target.getSorts();
+                var mutableInArguments = new LinkedHashSet<Variable>();
+                var mutableOutArguments = new LinkedHashSet<Variable>();
+                var parameters = target.getParameters();
                 for (int i = 0; i < arity; i++) {
                         var argument = arguments.get(i);
-                        var sort = sorts.get(i);
-                        if (!sort.isInstance(argument)) {
-                                throw new IllegalArgumentException("Required argument %d of %s to be of sort %s, but got %s instead"
-                                                .formatted(i, target, sort, argument.getSort()));
+                        var parameter = parameters.get(i);
+                        if (!parameter.isAssignable(argument)) {
+                                throw new IllegalArgumentException("Argument %d of %s is not assignable to parameter %s"
+                                                .formatted(i, target, parameter));
                         }
+                        switch (parameter.getDirection()) {
+                        case IN -> {
+                                if (mutableOutArguments.remove(argument)) {
+                                        checkInOutUnifiable(argument);
+                                }
+                                mutableInArguments.add(argument);
+                        }
+                        case OUT -> {
+                                if (mutableInArguments.contains(argument)) {
+                                        checkInOutUnifiable(argument);
+                                } else if (!mutableOutArguments.add(argument)) {
+                                        checkDuplicateOutUnifiable(argument);
+                                }
+                        }
+                        }
+                }
+                inArguments = Collections.unmodifiableSet(mutableInArguments);
+                outArguments = Collections.unmodifiableSet(mutableOutArguments);
+        }
+
+        private static void checkInOutUnifiable(Variable argument) {
+                if (!argument.isUnifiable()) {
+                        throw new IllegalArgumentException("Argument %s cannot appear with both %s and %s direction"
+                                        .formatted(argument, ParameterDirection.IN, ParameterDirection.OUT));
+                }
+        }
+
+        private static void checkDuplicateOutUnifiable(Variable argument) {
+                if (!argument.isUnifiable()) {
+                        throw new IllegalArgumentException("Argument %s cannot be bound multiple times".formatted(argument));
                 }
         }
 
@@ -39,6 +80,28 @@ public abstract class AbstractCallLiteral implements Literal {
                 return arguments;
         }
 
+        protected Set<Variable> getArgumentsOfDirection(ParameterDirection direction) {
+                return switch (direction) {
+                        case IN -> inArguments;
+                        case OUT -> outArguments;
+                };
+        }
+
+        @Override
+        public Set<Variable> getInputVariables(Set<? extends Variable> positiveVariablesInClause) {
+                var inputVariables = new LinkedHashSet<>(getArgumentsOfDirection(ParameterDirection.OUT));
+                inputVariables.retainAll(positiveVariablesInClause);
+                inputVariables.addAll(getArgumentsOfDirection(ParameterDirection.IN));
+                return Collections.unmodifiableSet(inputVariables);
+        }
+
+        @Override
+        public Set<Variable> getPrivateVariables(Set<? extends Variable> positiveVariablesInClause) {
+                var privateVariables = new LinkedHashSet<>(getArgumentsOfDirection(ParameterDirection.OUT));
+                privateVariables.removeAll(positiveVariablesInClause);
+                return Collections.unmodifiableSet(privateVariables);
+        }
+
         @Override
         public Literal substitute(Substitution substitution) {
                 var substitutedArguments = arguments.stream().map(substitution::getSubstitute).toList();
@@ -75,6 +138,6 @@ public abstract class AbstractCallLiteral implements Literal {
 
         @Override
         public int hashCode() {
-                return Objects.hash(target, arguments);
+                return Objects.hash(getClass(), target, arguments);
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AggregationLiteral.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AggregationLiteral.java
index df64839c..3a5eb5c7 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AggregationLiteral.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AggregationLiteral.java
@@ -1,11 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
 import tools.refinery.store.query.Constraint;
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
 import tools.refinery.store.query.substitution.Substitution;
-import tools.refinery.store.query.term.Aggregator;
-import tools.refinery.store.query.term.DataVariable;
-import tools.refinery.store.query.term.Variable;
+import tools.refinery.store.query.term.*;
 
 import java.util.List;
 import java.util.Objects;
@@ -23,14 +26,14 @@ public class AggregationLiteral<R, T> extends AbstractCallLiteral {
                         throw new IllegalArgumentException("Input variable %s must of type %s, got %s instead".formatted(
                                         inputVariable, aggregator.getInputType().getName(), inputVariable.getType().getName()));
                 }
+                if (!getArgumentsOfDirection(ParameterDirection.OUT).contains(inputVariable)) {
+                        throw new IllegalArgumentException("Input variable %s must be bound with direction %s in the argument list"
+                                        .formatted(inputVariable, ParameterDirection.OUT));
+                }
                 if (!resultVariable.getType().equals(aggregator.getResultType())) {
                         throw new IllegalArgumentException("Result variable %s must of type %s, got %s instead".formatted(
                                         resultVariable, aggregator.getResultType().getName(), resultVariable.getType().getName()));
                 }
-                if (!arguments.contains(inputVariable)) {
-                        throw new IllegalArgumentException("Input variable %s must appear in the argument list".formatted(
-                                        inputVariable));
-                }
                 if (arguments.contains(resultVariable)) {
                         throw new IllegalArgumentException("Result variable %s must not appear in the argument list".formatted(
                                         resultVariable));
@@ -53,11 +56,33 @@ public class AggregationLiteral<R, T> extends AbstractCallLiteral {
         }
 
         @Override
-        public Set<Variable> getBoundVariables() {
+        public Set<Variable> getOutputVariables() {
                 return Set.of(resultVariable);
         }
 
         @Override
+        public Set<Variable> getInputVariables(Set<? extends Variable> positiveVariablesInClause) {
+                if (positiveVariablesInClause.contains(inputVariable)) {
+                        throw new IllegalArgumentException("Aggregation variable %s must not be bound".formatted(inputVariable));
+                }
+                return super.getInputVariables(positiveVariablesInClause);
+        }
+
+        @Override
+        public Literal reduce() {
+                var reduction = getTarget().getReduction();
+                return switch (reduction) {
+                        case ALWAYS_FALSE -> {
+                                var emptyValue = aggregator.getEmptyResult();
+                                yield emptyValue == null ? BooleanLiteral.FALSE :
+                                                resultVariable.assign(new ConstantTerm<>(resultVariable.getType(), emptyValue));
+                        }
+                        case ALWAYS_TRUE -> throw new IllegalArgumentException("Trying to aggregate over an infinite set");
+                        case NOT_REDUCIBLE -> this;
+                };
+        }
+
+        @Override
         protected Literal doSubstitute(Substitution substitution, List<Variable> substitutedArguments) {
                 return new AggregationLiteral<>(substitution.getTypeSafeSubstitute(resultVariable), aggregator,
                                 substitution.getTypeSafeSubstitute(inputVariable), getTarget(), substitutedArguments);
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AssignLiteral.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AssignLiteral.java
index 52ac42d7..dbf999a2 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AssignLiteral.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AssignLiteral.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
@@ -6,6 +11,8 @@ import tools.refinery.store.query.term.DataVariable;
 import tools.refinery.store.query.term.Term;
 import tools.refinery.store.query.term.Variable;
 
+import java.util.Collections;
+import java.util.Objects;
 import java.util.Set;
 
 public record AssignLiteral<T>(DataVariable<T> variable, Term<T> term) implements Literal {
@@ -14,14 +21,29 @@ public record AssignLiteral<T>(DataVariable<T> variable, Term<T> term) implement
                         throw new IllegalArgumentException("Term %s must be of type %s, got %s instead".formatted(
                                         term, variable.getType().getName(), term.getType().getName()));
                 }
+                var inputVariables = term.getInputVariables();
+                if (inputVariables.contains(variable)) {
+                        throw new IllegalArgumentException("Result variable %s must not appear in the term %s".formatted(
+                                        variable, term));
+                }
         }
 
         @Override
-        public Set<Variable> getBoundVariables() {
+        public Set<Variable> getOutputVariables() {
                 return Set.of(variable);
         }
 
         @Override
+        public Set<Variable> getInputVariables(Set<? extends Variable> positiveVariablesInClause) {
+                return Collections.unmodifiableSet(term.getInputVariables());
+        }
+
+        @Override
+        public Set<Variable> getPrivateVariables(Set<? extends Variable> positiveVariablesInClause) {
+                return Set.of();
+        }
+
+        @Override
         public Literal substitute(Substitution substitution) {
                 return new AssignLiteral<>(substitution.getTypeSafeSubstitute(variable), term.substitute(substitution));
         }
@@ -36,9 +58,22 @@ public record AssignLiteral<T>(DataVariable<T> variable, Term<T> term) implement
                                 otherLetLiteral.term);
         }
 
-
         @Override
         public String toString() {
                 return "%s is (%s)".formatted(variable, term);
         }
+
+        @Override
+        public boolean equals(Object obj) {
+                if (obj == this) return true;
+                if (obj == null || obj.getClass() != this.getClass()) return false;
+                var that = (AssignLiteral<?>) obj;
+                return Objects.equals(this.variable, that.variable) &&
+                                Objects.equals(this.term, that.term);
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(getClass(), variable, term);
+        }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AssumeLiteral.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AssumeLiteral.java
index 0b4267b4..1ca04c77 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AssumeLiteral.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/AssumeLiteral.java
@@ -1,11 +1,18 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
 import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.ConstantTerm;
 import tools.refinery.store.query.term.Term;
 import tools.refinery.store.query.term.Variable;
-import tools.refinery.store.query.term.bool.BoolConstantTerm;
 
+import java.util.Collections;
+import java.util.Objects;
 import java.util.Set;
 
 public record AssumeLiteral(Term<Boolean> term) implements Literal {
@@ -17,11 +24,22 @@ public record AssumeLiteral(Term<Boolean> term) implements Literal {
         }
 
         @Override
-        public Set<Variable> getBoundVariables() {
+        public Set<Variable> getOutputVariables() {
                 return Set.of();
         }
 
         @Override
+        public Set<Variable> getInputVariables(Set<? extends Variable> positiveVariablesInClause) {
+                return Collections.unmodifiableSet(term.getInputVariables());
+        }
+
+        @Override
+        public Set<Variable> getPrivateVariables(Set<? extends Variable> positiveVariablesInClause) {
+                return Set.of();
+        }
+
+
+        @Override
         public Literal substitute(Substitution substitution) {
                 return new AssumeLiteral(term.substitute(substitution));
         }
@@ -36,18 +54,30 @@ public record AssumeLiteral(Term<Boolean> term) implements Literal {
         }
 
         @Override
-        public LiteralReduction getReduction() {
-                if (BoolConstantTerm.TRUE.equals(term)) {
-                        return LiteralReduction.ALWAYS_TRUE;
-                } else if (BoolConstantTerm.FALSE.equals(term)) {
-                        return LiteralReduction.ALWAYS_FALSE;
-                } else {
-                        return LiteralReduction.NOT_REDUCIBLE;
+        public Literal reduce() {
+                if (term instanceof ConstantTerm<Boolean> constantTerm) {
+                        // Return {@link BooleanLiteral#FALSE} for {@code false} or {@code null} literals.
+                        return Boolean.TRUE.equals(constantTerm.getValue()) ? BooleanLiteral.TRUE :
+                                        BooleanLiteral.FALSE;
                 }
+                return this;
         }
 
         @Override
         public String toString() {
                 return "(%s)".formatted(term);
         }
+
+        @Override
+        public boolean equals(Object obj) {
+                if (obj == this) return true;
+                if (obj == null || obj.getClass() != this.getClass()) return false;
+                var that = (AssumeLiteral) obj;
+                return Objects.equals(this.term, that.term);
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(getClass(), term);
+        }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/BooleanLiteral.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/BooleanLiteral.java
index 38be61a4..f312d202 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/BooleanLiteral.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/BooleanLiteral.java
@@ -1,8 +1,13 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
-import tools.refinery.store.query.term.Variable;
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
 import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Variable;
 
 import java.util.Set;
 
@@ -17,19 +22,24 @@ public enum BooleanLiteral implements CanNegate<BooleanLiteral> {
         }
 
         @Override
-        public Set<Variable> getBoundVariables() {
+        public Set<Variable> getOutputVariables() {
                 return Set.of();
         }
 
         @Override
-        public Literal substitute(Substitution substitution) {
-                // No variables to substitute.
-                return this;
+        public Set<Variable> getInputVariables(Set<? extends Variable> positiveVariablesInClause) {
+                return Set.of();
         }
 
         @Override
-        public LiteralReduction getReduction() {
-                return value ? LiteralReduction.ALWAYS_TRUE : LiteralReduction.ALWAYS_FALSE;
+        public Set<Variable> getPrivateVariables(Set<? extends Variable> positiveVariablesInClause) {
+                return Set.of();
+        }
+
+        @Override
+        public Literal substitute(Substitution substitution) {
+                // No variables to substitute.
+                return this;
         }
 
         @Override
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CallLiteral.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CallLiteral.java
index 78fae7f5..29772aee 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CallLiteral.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CallLiteral.java
@@ -1,26 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
 import tools.refinery.store.query.Constraint;
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
 import tools.refinery.store.query.substitution.Substitution;
-import tools.refinery.store.query.term.NodeSort;
+import tools.refinery.store.query.term.ParameterDirection;
 import tools.refinery.store.query.term.Variable;
 
-import java.util.List;
-import java.util.Objects;
-import java.util.Set;
+import java.util.*;
 
 public final class CallLiteral extends AbstractCallLiteral implements CanNegate<CallLiteral> {
         private final CallPolarity polarity;
 
         public CallLiteral(CallPolarity polarity, Constraint target, List<Variable> arguments) {
                 super(target, arguments);
+                var parameters = target.getParameters();
+                int arity = target.arity();
                 if (polarity.isTransitive()) {
-                        if (target.arity() != 2) {
+                        if (arity != 2) {
                                 throw new IllegalArgumentException("Transitive closures can only take binary relations");
                         }
-                        var sorts = target.getSorts();
-                        if (!sorts.get(0).equals(NodeSort.INSTANCE) || !sorts.get(1).equals(NodeSort.INSTANCE)) {
+                        if (parameters.get(0).isDataVariable() || parameters.get(1).isDataVariable()) {
                                 throw new IllegalArgumentException("Transitive closures can only be computed over nodes");
                         }
                 }
@@ -32,19 +36,43 @@ public final class CallLiteral extends AbstractCallLiteral implements CanNegate<
         }
 
         @Override
-        public Set<Variable> getBoundVariables() {
-                return polarity.isPositive() ? Set.copyOf(getArguments()) : Set.of();
+        protected Literal doSubstitute(Substitution substitution, List<Variable> substitutedArguments) {
+                return new CallLiteral(polarity, getTarget(), substitutedArguments);
         }
 
         @Override
-        protected Literal doSubstitute(Substitution substitution, List<Variable> substitutedArguments) {
-                return new CallLiteral(polarity, getTarget(), substitutedArguments);
+        public Set<Variable> getOutputVariables() {
+                if (polarity.isPositive()) {
+                        return getArgumentsOfDirection(ParameterDirection.OUT);
+                }
+                return Set.of();
+        }
+
+        @Override
+        public Set<Variable> getInputVariables(Set<? extends Variable> positiveVariablesInClause) {
+                if (polarity.isPositive()) {
+                        return getArgumentsOfDirection(ParameterDirection.IN);
+                }
+                return super.getInputVariables(positiveVariablesInClause);
+        }
+
+        @Override
+        public Set<Variable> getPrivateVariables(Set<? extends Variable> positiveVariablesInClause) {
+                if (polarity.isPositive()) {
+                        return Set.of();
+                }
+                return super.getPrivateVariables(positiveVariablesInClause);
         }
 
         @Override
-        public LiteralReduction getReduction() {
+        public Literal reduce() {
                 var reduction = getTarget().getReduction();
-                return polarity.isPositive() ? reduction : reduction.negate();
+                var negatedReduction = polarity.isPositive() ? reduction : reduction.negate();
+                return switch (negatedReduction) {
+                        case ALWAYS_TRUE -> BooleanLiteral.TRUE;
+                        case ALWAYS_FALSE -> BooleanLiteral.FALSE;
+                        default -> this;
+                };
         }
 
         @Override
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CallPolarity.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CallPolarity.java
index 84b4b771..ca70b0fd 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CallPolarity.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CallPolarity.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
 public enum CallPolarity {
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CanNegate.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CanNegate.java
index 3e159c43..35dcb3fb 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CanNegate.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CanNegate.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
 public interface CanNegate<T extends CanNegate<T>> extends Literal {
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/ConstantLiteral.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/ConstantLiteral.java
index 93fa3df0..73545620 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/ConstantLiteral.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/ConstantLiteral.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
@@ -5,15 +10,26 @@ import tools.refinery.store.query.substitution.Substitution;
 import tools.refinery.store.query.term.NodeVariable;
 import tools.refinery.store.query.term.Variable;
 
+import java.util.Objects;
 import java.util.Set;
 
 public record ConstantLiteral(NodeVariable variable, int nodeId) implements Literal {
         @Override
-        public Set<Variable> getBoundVariables() {
+        public Set<Variable> getOutputVariables() {
                 return Set.of(variable);
         }
 
         @Override
+        public Set<Variable> getInputVariables(Set<? extends Variable> positiveVariablesInClause) {
+                return Set.of();
+        }
+
+        @Override
+        public Set<Variable> getPrivateVariables(Set<? extends Variable> positiveVariablesInClause) {
+                return Set.of();
+        }
+
+        @Override
         public ConstantLiteral substitute(Substitution substitution) {
                 return new ConstantLiteral(substitution.getTypeSafeSubstitute(variable), nodeId);
         }
@@ -27,8 +43,23 @@ public record ConstantLiteral(NodeVariable variable, int nodeId) implements Lite
                 return helper.variableEqual(variable, otherConstantLiteral.variable) && nodeId == otherConstantLiteral.nodeId;
         }
 
+
         @Override
         public String toString() {
                 return "%s === @Constant %d".formatted(variable, nodeId);
         }
+
+        @Override
+        public boolean equals(Object obj) {
+                if (obj == this) return true;
+                if (obj == null || obj.getClass() != this.getClass()) return false;
+                var that = (ConstantLiteral) obj;
+                return Objects.equals(this.variable, that.variable) &&
+                                this.nodeId == that.nodeId;
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(getClass(), variable, nodeId);
+        }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CountLiteral.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CountLiteral.java
index 32e7ba3a..4d4749c8 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CountLiteral.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CountLiteral.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
 import tools.refinery.store.query.Constraint;
@@ -5,6 +10,7 @@ import tools.refinery.store.query.equality.LiteralEqualityHelper;
 import tools.refinery.store.query.substitution.Substitution;
 import tools.refinery.store.query.term.DataVariable;
 import tools.refinery.store.query.term.Variable;
+import tools.refinery.store.query.term.int_.IntTerms;
 
 import java.util.List;
 import java.util.Objects;
@@ -31,11 +37,23 @@ public class CountLiteral extends AbstractCallLiteral {
         }
 
         @Override
-        public Set<Variable> getBoundVariables() {
+        public Set<Variable> getOutputVariables() {
                 return Set.of(resultVariable);
         }
 
         @Override
+        public Literal reduce() {
+                var reduction = getTarget().getReduction();
+                return switch (reduction) {
+                        case ALWAYS_FALSE -> getResultVariable().assign(IntTerms.constant(0));
+                        // The only way a constant {@code true} predicate can be called in a negative position is to have all of
+                        // its arguments bound as input variables. Thus, there will only be a single match.
+                        case ALWAYS_TRUE -> getResultVariable().assign(IntTerms.constant(1));
+                        case NOT_REDUCIBLE -> this;
+                };
+        }
+
+        @Override
         protected Literal doSubstitute(Substitution substitution, List<Variable> substitutedArguments) {
                 return new CountLiteral(substitution.getTypeSafeSubstitute(resultVariable), getTarget(), substitutedArguments);
         }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/EquivalenceLiteral.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/EquivalenceLiteral.java
index 4dc86b98..28ba7625 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/EquivalenceLiteral.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/EquivalenceLiteral.java
@@ -1,18 +1,32 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
-import tools.refinery.store.query.term.NodeVariable;
-import tools.refinery.store.query.term.Variable;
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
 import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.Variable;
 
+import java.util.Objects;
 import java.util.Set;
 
 public record EquivalenceLiteral(boolean positive, NodeVariable left, NodeVariable right)
                 implements CanNegate<EquivalenceLiteral> {
         @Override
-        public Set<Variable> getBoundVariables() {
-                // If one side of a {@code positive} equivalence is bound, it may bind its other side, but we under-approximate
-                // this behavior by not binding any of the sides by default.
+        public Set<Variable> getOutputVariables() {
+                return Set.of(left);
+        }
+
+        @Override
+        public Set<Variable> getInputVariables(Set<? extends Variable> positiveVariablesInClause) {
+                return Set.of(right);
+        }
+
+        @Override
+        public Set<Variable> getPrivateVariables(Set<? extends Variable> positiveVariablesInClause) {
                 return Set.of();
         }
 
@@ -28,11 +42,11 @@ public record EquivalenceLiteral(boolean positive, NodeVariable left, NodeVariab
         }
 
         @Override
-        public LiteralReduction getReduction() {
+        public Literal reduce() {
                 if (left.equals(right)) {
-                        return positive ? LiteralReduction.ALWAYS_TRUE : LiteralReduction.ALWAYS_FALSE;
+                        return positive ? BooleanLiteral.TRUE : BooleanLiteral.FALSE;
                 }
-                return LiteralReduction.NOT_REDUCIBLE;
+                return this;
         }
 
         @Override
@@ -49,4 +63,19 @@ public record EquivalenceLiteral(boolean positive, NodeVariable left, NodeVariab
         public String toString() {
                 return "%s %s %s".formatted(left, positive ? "===" : "!==", right);
         }
+
+        @Override
+        public boolean equals(Object obj) {
+                if (obj == this) return true;
+                if (obj == null || obj.getClass() != this.getClass()) return false;
+                var that = (EquivalenceLiteral) obj;
+                return this.positive == that.positive &&
+                                Objects.equals(this.left, that.left) &&
+                                Objects.equals(this.right, that.right);
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(getClass(), positive, left, right);
+        }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/Literal.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/Literal.java
index 6347410e..ce6c11fe 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/Literal.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/Literal.java
@@ -1,18 +1,27 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
-import tools.refinery.store.query.term.Variable;
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
 import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Variable;
 
 import java.util.Set;
 
 public interface Literal {
-        Set<Variable> getBoundVariables();
+        Set<Variable> getOutputVariables();
+
+        Set<Variable> getInputVariables(Set<? extends Variable> positiveVariablesInClause);
+
+        Set<Variable> getPrivateVariables(Set<? extends Variable> positiveVariablesInClause);
 
         Literal substitute(Substitution substitution);
 
-        default LiteralReduction getReduction() {
-                return LiteralReduction.NOT_REDUCIBLE;
+        default Literal reduce() {
+                return this;
         }
 
         @SuppressWarnings("BooleanMethodIsAlwaysInverted")
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/Literals.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/Literals.java
index 89039352..b3a87811 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/Literals.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/Literals.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.literal;
 
 import tools.refinery.store.query.term.Term;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/CompositeSubstitution.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/CompositeSubstitution.java
deleted file mode 100644
index f8064ca2..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/CompositeSubstitution.java
+++ /dev/null
@@ -1,10 +0,0 @@
-package tools.refinery.store.query.substitution;
-
-import tools.refinery.store.query.term.Variable;
-
-public record CompositeSubstitution(Substitution first, Substitution second) implements Substitution {
-        @Override
-        public Variable getSubstitute(Variable variable) {
-                return second.getSubstitute(first.getSubstitute(variable));
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/MapBasedSubstitution.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/MapBasedSubstitution.java
index c7754619..a8201eef 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/MapBasedSubstitution.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/MapBasedSubstitution.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.substitution;
 
 import tools.refinery.store.query.term.Variable;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/RenewingSubstitution.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/RenewingSubstitution.java
index 7847e582..9b737ceb 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/RenewingSubstitution.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/RenewingSubstitution.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.substitution;
 
 import tools.refinery.store.query.term.Variable;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/StatelessSubstitution.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/StatelessSubstitution.java
index eed414d9..bb3803d3 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/StatelessSubstitution.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/StatelessSubstitution.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.substitution;
 
 import tools.refinery.store.query.term.Variable;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/Substitution.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/Substitution.java
index 99f84b9e..834fce12 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/Substitution.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/Substitution.java
@@ -1,6 +1,10 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.substitution;
 
-import tools.refinery.store.query.term.AnyDataVariable;
 import tools.refinery.store.query.term.DataVariable;
 import tools.refinery.store.query.term.NodeVariable;
 import tools.refinery.store.query.term.Variable;
@@ -14,16 +18,12 @@ public interface Substitution {
                 return substitute.asNodeVariable();
         }
 
-        default AnyDataVariable getTypeSafeSubstitute(AnyDataVariable variable) {
-                return getTypeSafeSubstitute((DataVariable<?>) variable);
-        }
-
         default <T> DataVariable<T> getTypeSafeSubstitute(DataVariable<T> variable) {
                 var substitute = getSubstitute(variable);
                 return substitute.asDataVariable(variable.getType());
         }
 
-        default Substitution andThen(Substitution second) {
-                return new CompositeSubstitution(this, second);
+        static SubstitutionBuilder builder() {
+                return new SubstitutionBuilder();
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/SubstitutionBuilder.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/SubstitutionBuilder.java
new file mode 100644
index 00000000..37fb6908
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/SubstitutionBuilder.java
@@ -0,0 +1,79 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.substitution;
+
+import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.Variable;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+@SuppressWarnings("UnusedReturnValue")
+public class SubstitutionBuilder {
+        private final Map<Variable, Variable> map = new HashMap<>();
+        private Substitution fallback;
+
+        SubstitutionBuilder() {
+                total();
+        }
+
+        public SubstitutionBuilder put(NodeVariable original, NodeVariable substitute) {
+                return putChecked(original, substitute);
+        }
+
+        public <T> SubstitutionBuilder put(DataVariable<T> original, DataVariable<T> substitute) {
+                return putChecked(original, substitute);
+        }
+
+        public SubstitutionBuilder putChecked(Variable original, Variable substitute) {
+                if (!original.tryGetType().equals(substitute.tryGetType())) {
+                        throw new IllegalArgumentException("Cannot substitute variable %s of sort %s with variable %s of sort %s"
+                                        .formatted(original, original.tryGetType().map(Class::getName).orElse("node"), substitute,
+                                                        substitute.tryGetType().map(Class::getName).orElse("node")));
+                }
+                if (map.containsKey(original)) {
+                        throw new IllegalArgumentException("Already has substitution for variable %s".formatted(original));
+                }
+                map.put(original, substitute);
+                return this;
+        }
+
+        public SubstitutionBuilder putManyChecked(List<Variable> originals, List<Variable> substitutes) {
+                int size = originals.size();
+                if (size != substitutes.size()) {
+                        throw new IllegalArgumentException("Cannot substitute %d variables %s with %d variables %s"
+                                        .formatted(size, originals, substitutes.size(), substitutes));
+                }
+                for (int i = 0; i < size; i++) {
+                        putChecked(originals.get(i), substitutes.get(i));
+                }
+                return this;
+        }
+
+        public SubstitutionBuilder fallback(Substitution newFallback) {
+                fallback = newFallback;
+                return this;
+        }
+
+        public SubstitutionBuilder total() {
+                return fallback(StatelessSubstitution.FAILING);
+        }
+
+        public SubstitutionBuilder partial() {
+                return fallback(StatelessSubstitution.IDENTITY);
+        }
+
+        public SubstitutionBuilder renewing() {
+                return fallback(new RenewingSubstitution());
+        }
+
+        public Substitution build() {
+                return map.isEmpty() ? fallback : new MapBasedSubstitution(Collections.unmodifiableMap(map), fallback);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/Substitutions.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/Substitutions.java
deleted file mode 100644
index 5d4654da..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/substitution/Substitutions.java
+++ /dev/null
@@ -1,33 +0,0 @@
-package tools.refinery.store.query.substitution;
-
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-import tools.refinery.store.query.term.Variable;
-
-import java.util.Map;
-
-public final class Substitutions {
-        private Substitutions() {
-                throw new IllegalStateException("This is a static utility class and should not be instantiate directly");
-        }
-
-        public static Substitution total(Map<Variable, Variable> map) {
-                return new MapBasedSubstitution(map, StatelessSubstitution.FAILING);
-        }
-
-        public static Substitution partial(Map<Variable, Variable> map) {
-                return new MapBasedSubstitution(map, StatelessSubstitution.IDENTITY);
-        }
-
-        public static Substitution renewing(Map<Variable, Variable> map) {
-                return new MapBasedSubstitution(map, renewing());
-        }
-
-        public static Substitution renewing() {
-                return new RenewingSubstitution();
-        }
-
-        public static Substitution compose(@Nullable Substitution first, @NotNull Substitution second) {
-                return first == null ? second : first.andThen(second);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AbstractTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AbstractTerm.java
new file mode 100644
index 00000000..d0ae3c12
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AbstractTerm.java
@@ -0,0 +1,41 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term;
+
+import tools.refinery.store.query.equality.LiteralEqualityHelper;
+
+import java.util.Objects;
+
+public abstract class AbstractTerm<T> implements Term<T> {
+        private final Class<T> type;
+
+        protected AbstractTerm(Class<T> type) {
+                this.type = type;
+        }
+
+        @Override
+        public boolean equalsWithSubstitution(LiteralEqualityHelper helper, AnyTerm other) {
+                return getClass().equals(other.getClass()) && type.equals(other.getType());
+        }
+
+        @Override
+        public Class<T> getType() {
+                return type;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                AbstractTerm<?> that = (AbstractTerm<?>) o;
+                return type.equals(that.type);
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(getClass(), type);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Aggregator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Aggregator.java
index 47421a94..0684a9d9 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Aggregator.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Aggregator.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import java.util.stream.Stream;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AnyDataVariable.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AnyDataVariable.java
index ecfefcf9..192c39c5 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AnyDataVariable.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AnyDataVariable.java
@@ -1,8 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import org.jetbrains.annotations.Nullable;
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
 
+import java.util.Optional;
 import java.util.Set;
 
 public abstract sealed class AnyDataVariable extends Variable implements AnyTerm permits DataVariable {
@@ -11,6 +17,11 @@ public abstract sealed class AnyDataVariable extends Variable implements AnyTerm
         }
 
         @Override
+        public Optional<Class<?>> tryGetType() {
+                return Optional.of(getType());
+        }
+
+        @Override
         public NodeVariable asNodeVariable() {
                 throw new IllegalStateException("%s is a data variable".formatted(this));
         }
@@ -26,6 +37,11 @@ public abstract sealed class AnyDataVariable extends Variable implements AnyTerm
         }
 
         @Override
+        public boolean isUnifiable() {
+                return false;
+        }
+
+        @Override
         public abstract AnyDataVariable renew(@Nullable String name);
 
         @Override
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AnyTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AnyTerm.java
index 8f998d45..c12c0166 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AnyTerm.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AnyTerm.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ArithmeticBinaryOperator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ArithmeticBinaryOperator.java
deleted file mode 100644
index 8706a046..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ArithmeticBinaryOperator.java
+++ /dev/null
@@ -1,26 +0,0 @@
-package tools.refinery.store.query.term;
-
-public enum ArithmeticBinaryOperator {
-        ADD("+", true),
-        SUB("-", true),
-        MUL("*", true),
-        DIV("/", true),
-        POW("**", true),
-        MIN("min", false),
-        MAX("max", false);
-
-        private final String text;
-        private final boolean infix;
-
-        ArithmeticBinaryOperator(String text, boolean infix) {
-                this.text = text;
-                this.infix = infix;
-        }
-
-        public String formatString(String left, String right) {
-                if (infix) {
-                        return "(%s) %s (%s)".formatted(left, text, right);
-                }
-                return "%s(%s, %s)".formatted(text, left, right);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ArithmeticBinaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ArithmeticBinaryTerm.java
deleted file mode 100644
index 887a1e6e..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ArithmeticBinaryTerm.java
+++ /dev/null
@@ -1,56 +0,0 @@
-package tools.refinery.store.query.term;
-
-import tools.refinery.store.query.equality.LiteralEqualityHelper;
-
-import java.util.Objects;
-
-public abstract class ArithmeticBinaryTerm<T> extends BinaryTerm<T, T, T> {
-        private final ArithmeticBinaryOperator operator;
-
-        protected ArithmeticBinaryTerm(ArithmeticBinaryOperator operator, Term<T> left, Term<T> right) {
-                super(left, right);
-                this.operator = operator;
-        }
-
-        @Override
-        public Class<T> getLeftType() {
-                return getType();
-        }
-
-        @Override
-        public Class<T> getRightType() {
-                return getType();
-        }
-
-        public ArithmeticBinaryOperator getOperator() {
-                return operator;
-        }
-
-        @Override
-        public boolean equalsWithSubstitution(LiteralEqualityHelper helper, AnyTerm other) {
-                if (!super.equalsWithSubstitution(helper, other)) {
-                        return false;
-                }
-                var otherArithmeticBinaryTerm = (ArithmeticBinaryTerm<?>) other;
-                return operator == otherArithmeticBinaryTerm.operator;
-        }
-
-        @Override
-        public String toString() {
-                return operator.formatString(getLeft().toString(), getRight().toString());
-        }
-
-        @Override
-        public boolean equals(Object o) {
-                if (this == o) return true;
-                if (o == null || getClass() != o.getClass()) return false;
-                if (!super.equals(o)) return false;
-                ArithmeticBinaryTerm<?> that = (ArithmeticBinaryTerm<?>) o;
-                return operator == that.operator;
-        }
-
-        @Override
-        public int hashCode() {
-                return Objects.hash(super.hashCode(), operator);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ArithmeticUnaryOperator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ArithmeticUnaryOperator.java
deleted file mode 100644
index 6a7c25db..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ArithmeticUnaryOperator.java
+++ /dev/null
@@ -1,16 +0,0 @@
-package tools.refinery.store.query.term;
-
-public enum ArithmeticUnaryOperator {
-        PLUS("+"),
-        MINUS("-");
-
-        private final String prefix;
-
-        ArithmeticUnaryOperator(String prefix) {
-                this.prefix = prefix;
-        }
-
-        public String formatString(String body) {
-                return "%s(%s)".formatted(prefix, body);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ArithmeticUnaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ArithmeticUnaryTerm.java
deleted file mode 100644
index b78239c7..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ArithmeticUnaryTerm.java
+++ /dev/null
@@ -1,51 +0,0 @@
-package tools.refinery.store.query.term;
-
-import tools.refinery.store.query.equality.LiteralEqualityHelper;
-
-import java.util.Objects;
-
-public abstract class ArithmeticUnaryTerm<T> extends UnaryTerm<T, T> {
-        private final ArithmeticUnaryOperator operator;
-
-        protected ArithmeticUnaryTerm(ArithmeticUnaryOperator operator, Term<T> body) {
-                super(body);
-                this.operator = operator;
-        }
-
-        @Override
-        public Class<T> getBodyType() {
-                return getType();
-        }
-
-        public ArithmeticUnaryOperator getOperator() {
-                return operator;
-        }
-
-        @Override
-        public boolean equalsWithSubstitution(LiteralEqualityHelper helper, AnyTerm other) {
-                if (!super.equalsWithSubstitution(helper, other)) {
-                        return false;
-                }
-                var otherArithmeticUnaryTerm = (ArithmeticUnaryTerm<?>) other;
-                return operator == otherArithmeticUnaryTerm.operator;
-        }
-
-        @Override
-        public String toString() {
-                return operator.formatString(getBody().toString());
-        }
-
-        @Override
-        public boolean equals(Object o) {
-                if (this == o) return true;
-                if (o == null || getClass() != o.getClass()) return false;
-                if (!super.equals(o)) return false;
-                ArithmeticUnaryTerm<?> that = (ArithmeticUnaryTerm<?>) o;
-                return operator == that.operator;
-        }
-
-        @Override
-        public int hashCode() {
-                return Objects.hash(super.hashCode(), operator);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AssignedValue.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AssignedValue.java
index 465e690f..0cf30aa6 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AssignedValue.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/AssignedValue.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import tools.refinery.store.query.literal.Literal;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/BinaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/BinaryTerm.java
index 34f48ccc..8ad17839 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/BinaryTerm.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/BinaryTerm.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
@@ -9,26 +14,35 @@ import java.util.HashSet;
 import java.util.Objects;
 import java.util.Set;
 
-public abstract class BinaryTerm<R, T1, T2> implements Term<R> {
+public abstract class BinaryTerm<R, T1, T2> extends AbstractTerm<R> {
+        private final Class<T1> leftType;
+        private final Class<T2> rightType;
         private final Term<T1> left;
         private final Term<T2> right;
 
-        protected BinaryTerm(Term<T1> left, Term<T2> right) {
-                if (!left.getType().equals(getLeftType())) {
-                        throw new IllegalArgumentException("Expected left %s to be of type %s, got %s instead".formatted(left,
-                                        getLeftType().getName(), left.getType().getName()));
+        protected BinaryTerm(Class<R> type, Class<T1> leftType, Class<T2> rightType, Term<T1> left, Term<T2> right) {
+                super(type);
+                if (!left.getType().equals(leftType)) {
+                        throw new IllegalArgumentException("Expected left %s to be of type %s, got %s instead".formatted(
+                                        left, leftType.getName(), left.getType().getName()));
                 }
-                if (!right.getType().equals(getRightType())) {
-                        throw new IllegalArgumentException("Expected right %s to be of type %s, got %s instead".formatted(right,
-                                        getRightType().getName(), right.getType().getName()));
+                if (!right.getType().equals(rightType)) {
+                        throw new IllegalArgumentException("Expected right %s to be of type %s, got %s instead".formatted(
+                                        right, rightType.getName(), right.getType().getName()));
                 }
+                this.leftType = leftType;
+                this.rightType = rightType;
                 this.left = left;
                 this.right = right;
         }
 
-        public abstract Class<T1> getLeftType();
+        public Class<T1> getLeftType() {
+                return leftType;
+        }
 
-        public abstract Class<T2> getRightType();
+        public Class<T2> getRightType() {
+                return rightType;
+        }
 
         public Term<T1> getLeft() {
                 return left;
@@ -55,12 +69,14 @@ public abstract class BinaryTerm<R, T1, T2> implements Term<R> {
 
         @Override
         public boolean equalsWithSubstitution(LiteralEqualityHelper helper, AnyTerm other) {
-                if (getClass() != other.getClass()) {
+                if (!super.equalsWithSubstitution(helper, other)) {
                         return false;
                 }
                 var otherBinaryTerm = (BinaryTerm<?, ?, ?>) other;
-                return left.equalsWithSubstitution(helper, otherBinaryTerm.left) && right.equalsWithSubstitution(helper,
-                                otherBinaryTerm.right);
+                return leftType.equals(otherBinaryTerm.leftType) &&
+                                rightType.equals(otherBinaryTerm.rightType) &&
+                                left.equalsWithSubstitution(helper, otherBinaryTerm.left) &&
+                                right.equalsWithSubstitution(helper, otherBinaryTerm.right);
         }
 
         @Override
@@ -82,12 +98,16 @@ public abstract class BinaryTerm<R, T1, T2> implements Term<R> {
         public boolean equals(Object o) {
                 if (this == o) return true;
                 if (o == null || getClass() != o.getClass()) return false;
+                if (!super.equals(o)) return false;
                 BinaryTerm<?, ?, ?> that = (BinaryTerm<?, ?, ?>) o;
-                return left.equals(that.left) && right.equals(that.right);
+                return Objects.equals(leftType, that.leftType) &&
+                                Objects.equals(rightType, that.rightType) &&
+                                Objects.equals(left, that.left) &&
+                                Objects.equals(right, that.right);
         }
 
         @Override
         public int hashCode() {
-                return Objects.hash(getClass(), left, right);
+                return Objects.hash(super.hashCode(), leftType, rightType, left, right);
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ComparisonOperator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ComparisonOperator.java
deleted file mode 100644
index 44dcce10..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ComparisonOperator.java
+++ /dev/null
@@ -1,20 +0,0 @@
-package tools.refinery.store.query.term;
-
-public enum ComparisonOperator {
-        EQ("=="),
-        NOT_EQ("!="),
-        LESS("<"),
-        LESS_EQ("<="),
-        GREATER(">"),
-        GREATER_EQ(">=");
-
-        private final String text;
-
-        ComparisonOperator(String text) {
-                this.text = text;
-        }
-
-        public String formatString(String left, String right) {
-                return "(%s) %s (%s)".formatted(left, text, right);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ComparisonTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ComparisonTerm.java
deleted file mode 100644
index 320d42df..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ComparisonTerm.java
+++ /dev/null
@@ -1,63 +0,0 @@
-package tools.refinery.store.query.term;
-
-import tools.refinery.store.query.equality.LiteralEqualityHelper;
-
-import java.util.Objects;
-
-public abstract class ComparisonTerm<T> extends BinaryTerm<Boolean, T, T> {
-        private final ComparisonOperator operator;
-
-        protected ComparisonTerm(ComparisonOperator operator, Term<T> left, Term<T> right) {
-                super(left, right);
-                this.operator = operator;
-        }
-
-        @Override
-        public Class<Boolean> getType() {
-                return Boolean.class;
-        }
-
-        public abstract Class<T> getOperandType();
-
-        @Override
-        public Class<T> getLeftType() {
-                return getOperandType();
-        }
-
-        @Override
-        public Class<T> getRightType() {
-                return getOperandType();
-        }
-
-        public ComparisonOperator getOperator() {
-                return operator;
-        }
-
-        @Override
-        public boolean equalsWithSubstitution(LiteralEqualityHelper helper, AnyTerm other) {
-                if (!super.equalsWithSubstitution(helper, other)) {
-                        return false;
-                }
-                var otherComparisonTerm = (ComparisonTerm<?>) other;
-                return operator == otherComparisonTerm.operator;
-        }
-
-        @Override
-        public String toString() {
-                return operator.formatString(getLeft().toString(), getRight().toString());
-        }
-
-        @Override
-        public boolean equals(Object o) {
-                if (this == o) return true;
-                if (o == null || getClass() != o.getClass()) return false;
-                if (!super.equals(o)) return false;
-                ComparisonTerm<?> that = (ComparisonTerm<?>) o;
-                return operator == that.operator;
-        }
-
-        @Override
-        public int hashCode() {
-                return Objects.hash(super.hashCode(), operator);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ConstantTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ConstantTerm.java
index 2185fe37..2f6c56d1 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ConstantTerm.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ConstantTerm.java
@@ -1,24 +1,26 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
 import tools.refinery.store.query.substitution.Substitution;
 import tools.refinery.store.query.valuation.Valuation;
 
+import java.util.Objects;
 import java.util.Set;
 
-public record ConstantTerm<T>(Class<T> type, T value) implements Term<T> {
-        public ConstantTerm {
-                if (value == null) {
-                        throw new IllegalArgumentException("value should not be null");
-                }
-                if (!type.isInstance(value)) {
-                        throw new IllegalArgumentException("value %s is not an instance of %s".formatted(value, type.getName()));
-                }
-        }
+public final class ConstantTerm<T> extends AbstractTerm<T> {
+        private final T value;
 
-        @Override
-        public Class<T> getType() {
-                return type;
+        public ConstantTerm(Class<T> type, T value) {
+                super(type);
+                if (value != null && !type.isInstance(value)) {
+                        throw new IllegalArgumentException("Value %s is not an instance of %s".formatted(value, type.getName()));
+                }
+                this.value = value;
         }
 
         public T getValue() {
@@ -37,7 +39,11 @@ public record ConstantTerm<T>(Class<T> type, T value) implements Term<T> {
 
         @Override
         public boolean equalsWithSubstitution(LiteralEqualityHelper helper, AnyTerm other) {
-                return equals(other);
+                if (!super.equalsWithSubstitution(helper, other)) {
+                        return false;
+                }
+                var otherConstantTerm = (ConstantTerm<?>) other;
+                return Objects.equals(value, otherConstantTerm.value);
         }
 
         @Override
@@ -47,6 +53,19 @@ public record ConstantTerm<T>(Class<T> type, T value) implements Term<T> {
 
         @Override
         public String toString() {
-                return getValue().toString();
+                return value.toString();
+        }
+
+        @Override
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                ConstantTerm<?> that = (ConstantTerm<?>) o;
+                return Objects.equals(value, that.value);
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(value);
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/DataSort.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/DataSort.java
deleted file mode 100644
index 4fb44492..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/DataSort.java
+++ /dev/null
@@ -1,29 +0,0 @@
-package tools.refinery.store.query.term;
-
-import org.jetbrains.annotations.Nullable;
-
-public record DataSort<T>(Class<T> type) implements Sort {
-        public static final DataSort<Integer> INT = new DataSort<>(Integer.class);
-
-        public static final DataSort<Boolean> BOOL = new DataSort<>(Boolean.class);
-
-        @Override
-        public boolean isInstance(Variable variable) {
-                return variable instanceof DataVariable<?> dataVariable && type.equals(dataVariable.getType());
-        }
-
-        @Override
-        public DataVariable<T> newInstance(@Nullable String name) {
-                return Variable.of(name, type);
-        }
-
-        @Override
-        public DataVariable<T> newInstance() {
-                return newInstance(null);
-        }
-
-        @Override
-        public String toString() {
-                return type.getName();
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/DataVariable.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/DataVariable.java
index af070ca7..00950360 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/DataVariable.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/DataVariable.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import org.jetbrains.annotations.Nullable;
@@ -17,11 +22,6 @@ public final class DataVariable<T> extends AnyDataVariable implements Term<T> {
         }
 
         @Override
-        public DataSort<T> getSort() {
-                return new DataSort<>(getType());
-        }
-
-        @Override
         public Class<T> getType() {
                 return type;
         }
@@ -37,11 +37,6 @@ public final class DataVariable<T> extends AnyDataVariable implements Term<T> {
         }
 
         @Override
-        public NodeVariable asNodeVariable() {
-                throw new IllegalStateException("%s is a data variable".formatted(this));
-        }
-
-        @Override
         public <U> DataVariable<U> asDataVariable(Class<U> newType) {
                 if (!getType().equals(newType)) {
                         throw new IllegalStateException("%s is not of type %s but of type %s".formatted(this, newType.getName(),
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ExtremeValueAggregator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ExtremeValueAggregator.java
index 57ff597c..657cb631 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ExtremeValueAggregator.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ExtremeValueAggregator.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import java.util.Comparator;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/NodeSort.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/NodeSort.java
deleted file mode 100644
index 1a4b2d4b..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/NodeSort.java
+++ /dev/null
@@ -1,30 +0,0 @@
-package tools.refinery.store.query.term;
-
-import org.jetbrains.annotations.Nullable;
-
-public final class NodeSort implements Sort {
-        public static final NodeSort INSTANCE = new NodeSort();
-
-        private NodeSort() {
-        }
-
-        @Override
-        public boolean isInstance(Variable variable) {
-                return variable instanceof NodeVariable;
-        }
-
-        @Override
-        public NodeVariable newInstance(@Nullable String name) {
-                return new NodeVariable(name);
-        }
-
-        @Override
-        public NodeVariable newInstance() {
-                return newInstance(null);
-        }
-
-        @Override
-        public String toString() {
-                return "<node>";
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/NodeVariable.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/NodeVariable.java
index 7419aaad..a2f3261f 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/NodeVariable.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/NodeVariable.java
@@ -1,17 +1,29 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import org.jetbrains.annotations.Nullable;
 import tools.refinery.store.query.literal.ConstantLiteral;
 import tools.refinery.store.query.literal.EquivalenceLiteral;
 
+import java.util.Optional;
+
 public final class NodeVariable extends Variable {
         NodeVariable(@Nullable String name) {
                 super(name);
         }
 
         @Override
-        public NodeSort getSort() {
-                return NodeSort.INSTANCE;
+        public Optional<Class<?>> tryGetType() {
+                return Optional.empty();
+        }
+
+        @Override
+        public boolean isUnifiable() {
+                return true;
         }
 
         @Override
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/OpaqueTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/OpaqueTerm.java
deleted file mode 100644
index 8faa9c75..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/OpaqueTerm.java
+++ /dev/null
@@ -1,80 +0,0 @@
-package tools.refinery.store.query.term;
-
-import tools.refinery.store.query.equality.LiteralEqualityHelper;
-import tools.refinery.store.query.substitution.Substitution;
-import tools.refinery.store.query.substitution.Substitutions;
-import tools.refinery.store.query.valuation.Valuation;
-
-import java.util.Objects;
-import java.util.Set;
-import java.util.function.Function;
-import java.util.stream.Collectors;
-
-public final class OpaqueTerm<T> implements Term<T> {
-        private final Class<T> type;
-        private final Function<? super Valuation, ? extends T> evaluator;
-        private final Set<AnyDataVariable> variables;
-        private final Substitution substitution;
-
-        public OpaqueTerm(Class<T> type, Function<? super Valuation, ? extends T> evaluator,
-                                          Set<? extends AnyDataVariable> variables) {
-                this(type, evaluator, variables, null);
-        }
-
-        private OpaqueTerm(Class<T> type, Function<? super Valuation, ? extends T> evaluator,
-                                           Set<? extends AnyDataVariable> variables, Substitution substitution) {
-                this.type = type;
-                this.evaluator = evaluator;
-                this.variables = Set.copyOf(variables);
-                this.substitution = substitution;
-        }
-
-        @Override
-        public Class<T> getType() {
-                return type;
-        }
-
-        @Override
-        public Set<AnyDataVariable> getInputVariables() {
-                return variables;
-        }
-
-        @Override
-        public T evaluate(Valuation valuation) {
-                return evaluator.apply(valuation.substitute(substitution));
-        }
-
-        @Override
-        public Term<T> substitute(Substitution newSubstitution) {
-                var substitutedVariables = variables.stream()
-                                .map(newSubstitution::getTypeSafeSubstitute)
-                                .collect(Collectors.toUnmodifiableSet());
-                return new OpaqueTerm<>(type, evaluator, substitutedVariables,
-                                Substitutions.compose(substitution, newSubstitution));
-        }
-
-        @Override
-        public boolean equalsWithSubstitution(LiteralEqualityHelper helper, AnyTerm other) {
-                // Cannot inspect the opaque evaluator for deep equality.
-                return equals(other);
-        }
-
-        @Override
-        public String toString() {
-                return "<opaque>";
-        }
-
-        @Override
-        public boolean equals(Object o) {
-                if (this == o) return true;
-                if (o == null || getClass() != o.getClass()) return false;
-                OpaqueTerm<?> that = (OpaqueTerm<?>) o;
-                return type.equals(that.type) && evaluator.equals(that.evaluator) && Objects.equals(substitution,
-                                that.substitution);
-        }
-
-        @Override
-        public int hashCode() {
-                return Objects.hash(type, evaluator, substitution);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Parameter.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Parameter.java
new file mode 100644
index 00000000..e5a0cdf1
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Parameter.java
@@ -0,0 +1,60 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term;
+
+import java.util.Objects;
+import java.util.Optional;
+
+public class Parameter {
+        public static final Parameter NODE_OUT = new Parameter(null, ParameterDirection.OUT);
+
+        private final Class<?> dataType;
+        private final ParameterDirection direction;
+
+        public Parameter(Class<?> dataType, ParameterDirection direction) {
+                this.dataType = dataType;
+                this.direction = direction;
+        }
+
+        public boolean isNodeVariable() {
+                return dataType == null;
+        }
+
+        public boolean isDataVariable() {
+                return !isNodeVariable();
+        }
+
+        public Optional<Class<?>> tryGetType() {
+                return Optional.ofNullable(dataType);
+        }
+
+        public ParameterDirection getDirection() {
+                return direction;
+        }
+
+        public boolean isAssignable(Variable variable) {
+                if (variable instanceof AnyDataVariable dataVariable) {
+                        return dataVariable.getType().equals(dataType);
+                } else if (variable instanceof NodeVariable) {
+                        return !isDataVariable();
+                } else {
+                        throw new IllegalArgumentException("Unknown variable " + variable);
+                }
+        }
+
+        @Override
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                Parameter parameter = (Parameter) o;
+                return Objects.equals(dataType, parameter.dataType) && direction == parameter.direction;
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(dataType, direction);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ParameterDirection.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ParameterDirection.java
new file mode 100644
index 00000000..cd0739be
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/ParameterDirection.java
@@ -0,0 +1,22 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term;
+
+public enum ParameterDirection {
+        OUT("@Out"),
+        IN("@In");
+
+        private final String name;
+
+        ParameterDirection(String name) {
+                this.name = name;
+        }
+
+        @Override
+        public String toString() {
+                return name;
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Sort.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Sort.java
deleted file mode 100644
index 622bcfce..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Sort.java
+++ /dev/null
@@ -1,11 +0,0 @@
-package tools.refinery.store.query.term;
-
-import org.jetbrains.annotations.Nullable;
-
-public sealed interface Sort permits DataSort, NodeSort {
-        boolean isInstance(Variable variable);
-
-        Variable newInstance(@Nullable String name);
-
-        Variable newInstance();
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/StatefulAggregate.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/StatefulAggregate.java
index 7ce91305..ab310556 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/StatefulAggregate.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/StatefulAggregate.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 public interface StatefulAggregate<R, T> {
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/StatefulAggregator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/StatefulAggregator.java
index c215a511..df746a90 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/StatefulAggregator.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/StatefulAggregator.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import java.util.stream.Stream;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/StatelessAggregator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/StatelessAggregator.java
index 74dbd335..a094919e 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/StatelessAggregator.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/StatelessAggregator.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import java.util.stream.Stream;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Term.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Term.java
index 95434db2..e6818b88 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Term.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Term.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import tools.refinery.store.query.literal.AssignLiteral;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/UnaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/UnaryTerm.java
index 4083111a..a46ebe31 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/UnaryTerm.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/UnaryTerm.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
@@ -7,18 +12,23 @@ import tools.refinery.store.query.valuation.Valuation;
 import java.util.Objects;
 import java.util.Set;
 
-public abstract class UnaryTerm<R, T> implements Term<R> {
+public abstract class UnaryTerm<R, T> extends AbstractTerm<R> {
+        private final Class<T> bodyType;
         private final Term<T> body;
 
-        protected UnaryTerm(Term<T> body) {
-                if (!body.getType().equals(getBodyType())) {
+        protected UnaryTerm(Class<R> type, Class<T> bodyType, Term<T> body) {
+                super(type);
+                if (!body.getType().equals(bodyType)) {
                         throw new IllegalArgumentException("Expected body %s to be of type %s, got %s instead".formatted(body,
-                                        getBodyType().getName(), body.getType().getName()));
+                                        bodyType.getName(), body.getType().getName()));
                 }
+                this.bodyType = bodyType;
                 this.body = body;
         }
 
-        public abstract Class<T> getBodyType();
+        public Class<T> getBodyType() {
+                return bodyType;
+        }
 
         public Term<T> getBody() {
                 return body;
@@ -34,11 +44,11 @@ public abstract class UnaryTerm<R, T> implements Term<R> {
 
         @Override
         public boolean equalsWithSubstitution(LiteralEqualityHelper helper, AnyTerm other) {
-                if (getClass() != other.getClass()) {
+                if (!super.equalsWithSubstitution(helper, other)) {
                         return false;
                 }
                 var otherUnaryTerm = (UnaryTerm<?, ?>) other;
-                return body.equalsWithSubstitution(helper, otherUnaryTerm.body);
+                return bodyType.equals(otherUnaryTerm.bodyType) && body.equalsWithSubstitution(helper, otherUnaryTerm.body);
         }
 
         @Override
@@ -57,12 +67,13 @@ public abstract class UnaryTerm<R, T> implements Term<R> {
         public boolean equals(Object o) {
                 if (this == o) return true;
                 if (o == null || getClass() != o.getClass()) return false;
+                if (!super.equals(o)) return false;
                 UnaryTerm<?, ?> unaryTerm = (UnaryTerm<?, ?>) o;
-                return body.equals(unaryTerm.body);
+                return Objects.equals(bodyType, unaryTerm.bodyType) && Objects.equals(body, unaryTerm.body);
         }
 
         @Override
         public int hashCode() {
-                return Objects.hash(getClass(), body);
+                return Objects.hash(super.hashCode(), bodyType, body);
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Variable.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Variable.java
index 957e10f8..a0268c8e 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Variable.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/Variable.java
@@ -1,9 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term;
 
 import org.jetbrains.annotations.Nullable;
 import tools.refinery.store.query.dnf.DnfUtils;
 
 import java.util.Objects;
+import java.util.Optional;
 
 public abstract sealed class Variable permits AnyDataVariable, NodeVariable {
         private final String explicitName;
@@ -14,7 +20,7 @@ public abstract sealed class Variable permits AnyDataVariable, NodeVariable {
                 uniqueName = DnfUtils.generateUniqueName(name);
         }
 
-        public abstract Sort getSort();
+        public abstract Optional<Class<?>> tryGetType();
 
         public String getName() {
                 return explicitName == null ? uniqueName : explicitName;
@@ -32,6 +38,8 @@ public abstract sealed class Variable permits AnyDataVariable, NodeVariable {
                 return uniqueName;
         }
 
+        public abstract boolean isUnifiable();
+
         public abstract Variable renew(@Nullable String name);
 
         public abstract Variable renew();
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolAndTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolAndTerm.java
new file mode 100644
index 00000000..f9e1c06f
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolAndTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.bool;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class BoolAndTerm extends BoolBinaryTerm {
+        public BoolAndTerm(Term<Boolean> left, Term<Boolean> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Boolean> doSubstitute(Substitution substitution, Term<Boolean> substitutedLeft,
+                                                                          Term<Boolean> substitutedRight) {
+                return new BoolAndTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Boolean doEvaluate(Boolean leftValue, Boolean rightValue) {
+                return leftValue && rightValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(%s && %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolBinaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolBinaryTerm.java
new file mode 100644
index 00000000..a85aa63a
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolBinaryTerm.java
@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.bool;
+
+import tools.refinery.store.query.term.BinaryTerm;
+import tools.refinery.store.query.term.Term;
+
+public abstract class BoolBinaryTerm extends BinaryTerm<Boolean, Boolean, Boolean> {
+        protected BoolBinaryTerm(Term<Boolean> left, Term<Boolean> right) {
+                super(Boolean.class, Boolean.class, Boolean.class, left, right);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolConstantTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolConstantTerm.java
deleted file mode 100644
index 5079f1ce..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolConstantTerm.java
+++ /dev/null
@@ -1,16 +0,0 @@
-package tools.refinery.store.query.term.bool;
-
-import tools.refinery.store.query.term.ConstantTerm;
-
-public final class BoolConstantTerm {
-        public static final ConstantTerm<Boolean> TRUE = new ConstantTerm<>(Boolean.class, true);
-        public static final ConstantTerm<Boolean> FALSE = new ConstantTerm<>(Boolean.class, false);
-
-        private BoolConstantTerm() {
-                throw new IllegalStateException("This is a static utility class and should not be instantiated directly");
-        }
-
-        public static ConstantTerm<Boolean> valueOf(boolean boolValue) {
-                return boolValue ? TRUE : FALSE;
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolLogicBinaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolLogicBinaryTerm.java
deleted file mode 100644
index d85f864d..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolLogicBinaryTerm.java
+++ /dev/null
@@ -1,78 +0,0 @@
-package tools.refinery.store.query.term.bool;
-
-import tools.refinery.store.query.equality.LiteralEqualityHelper;
-import tools.refinery.store.query.substitution.Substitution;
-import tools.refinery.store.query.term.*;
-
-import java.util.Objects;
-
-public class BoolLogicBinaryTerm extends BinaryTerm<Boolean, Boolean, Boolean> {
-        private final LogicBinaryOperator operator;
-
-        protected BoolLogicBinaryTerm(LogicBinaryOperator operator, Term<Boolean> left, Term<Boolean> right) {
-                super(left, right);
-                this.operator = operator;
-        }
-
-        @Override
-        public Class<Boolean> getType() {
-                return Boolean.class;
-        }
-
-        @Override
-        public Class<Boolean> getLeftType() {
-                return getType();
-        }
-
-        @Override
-        public Class<Boolean> getRightType() {
-                return getType();
-        }
-
-        public LogicBinaryOperator getOperator() {
-                return operator;
-        }
-
-        @Override
-        public boolean equalsWithSubstitution(LiteralEqualityHelper helper, AnyTerm other) {
-                if (!super.equalsWithSubstitution(helper, other)) {
-                        return false;
-                }
-                var otherBoolLogicBinaryTerm = (BoolLogicBinaryTerm) other;
-                return operator == otherBoolLogicBinaryTerm.operator;
-        }
-
-        @Override
-        public Term<Boolean> doSubstitute(Substitution substitution, Term<Boolean> substitutedLeft,
-                                                                          Term<Boolean> substitutedRight) {
-                return new BoolLogicBinaryTerm(getOperator(), substitutedLeft, substitutedRight);
-        }
-
-        @Override
-        protected Boolean doEvaluate(Boolean leftValue, Boolean rightValue) {
-                return switch (getOperator()) {
-                        case AND -> leftValue && rightValue;
-                        case OR -> leftValue || rightValue;
-                        case XOR -> leftValue ^ rightValue;
-                };
-        }
-
-        @Override
-        public String toString() {
-                return operator.formatString(getLeft().toString(), getRight().toString());
-        }
-
-        @Override
-        public boolean equals(Object o) {
-                if (this == o) return true;
-                if (o == null || getClass() != o.getClass()) return false;
-                if (!super.equals(o)) return false;
-                BoolLogicBinaryTerm that = (BoolLogicBinaryTerm) o;
-                return operator == that.operator;
-        }
-
-        @Override
-        public int hashCode() {
-                return Objects.hash(super.hashCode(), operator);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolNotTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolNotTerm.java
index 855139b5..8d3382b3 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolNotTerm.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolNotTerm.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term.bool;
 
 import tools.refinery.store.query.substitution.Substitution;
@@ -6,17 +11,7 @@ import tools.refinery.store.query.term.UnaryTerm;
 
 public class BoolNotTerm extends UnaryTerm<Boolean, Boolean> {
         protected BoolNotTerm(Term<Boolean> body) {
-                super(body);
-        }
-
-        @Override
-        public Class<Boolean> getType() {
-                return Boolean.class;
-        }
-
-        @Override
-        public Class<Boolean> getBodyType() {
-                return getType();
+                super(Boolean.class, Boolean.class, body);
         }
 
         @Override
@@ -31,6 +26,6 @@ public class BoolNotTerm extends UnaryTerm<Boolean, Boolean> {
 
         @Override
         public String toString() {
-                return "!(%s)".formatted(getBody());
+                return "(!%s)".formatted(getBody());
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolOrTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolOrTerm.java
new file mode 100644
index 00000000..b5195d52
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolOrTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.bool;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class BoolOrTerm extends BoolBinaryTerm {
+        public BoolOrTerm(Term<Boolean> left, Term<Boolean> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Boolean> doSubstitute(Substitution substitution, Term<Boolean> substitutedLeft,
+                                                                          Term<Boolean> substitutedRight) {
+                return new BoolOrTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Boolean doEvaluate(Boolean leftValue, Boolean rightValue) {
+                return leftValue || rightValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(%s || %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolTerms.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolTerms.java
index 3d6c8d9d..fa54f686 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolTerms.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolTerms.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term.bool;
 
 import tools.refinery.store.query.term.ConstantTerm;
@@ -8,23 +13,23 @@ public final class BoolTerms {
                 throw new IllegalArgumentException("This is a static utility class and should not be instantiated directly");
         }
 
-        public static ConstantTerm<Boolean> constant(boolean value) {
-                return BoolConstantTerm.valueOf(value);
+        public static Term<Boolean> constant(Boolean value) {
+                return new ConstantTerm<>(Boolean.class, value);
         }
 
-        public static BoolNotTerm not(Term<Boolean> body) {
+        public static Term<Boolean> not(Term<Boolean> body) {
                 return new BoolNotTerm(body);
         }
 
-        public static BoolLogicBinaryTerm and(Term<Boolean> left, Term<Boolean> right) {
-                return new BoolLogicBinaryTerm(LogicBinaryOperator.AND, left, right);
+        public static Term<Boolean> and(Term<Boolean> left, Term<Boolean> right) {
+                return new BoolAndTerm(left, right);
         }
 
-        public static BoolLogicBinaryTerm or(Term<Boolean> left, Term<Boolean> right) {
-                return new BoolLogicBinaryTerm(LogicBinaryOperator.OR, left, right);
+        public static Term<Boolean> or(Term<Boolean> left, Term<Boolean> right) {
+                return new BoolOrTerm(left, right);
         }
 
-        public static BoolLogicBinaryTerm xor(Term<Boolean> left, Term<Boolean> right) {
-                return new BoolLogicBinaryTerm(LogicBinaryOperator.XOR, left, right);
+        public static Term<Boolean> xor(Term<Boolean> left, Term<Boolean> right) {
+                return new BoolXorTerm(left, right);
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolXorTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolXorTerm.java
new file mode 100644
index 00000000..7478b8a5
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/BoolXorTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.bool;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class BoolXorTerm extends BoolBinaryTerm {
+        public BoolXorTerm(Term<Boolean> left, Term<Boolean> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Boolean> doSubstitute(Substitution substitution, Term<Boolean> substitutedLeft,
+                                                                          Term<Boolean> substitutedRight) {
+                return new BoolXorTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Boolean doEvaluate(Boolean leftValue, Boolean rightValue) {
+                return leftValue ^ rightValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(%s ^^ %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/LogicBinaryOperator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/LogicBinaryOperator.java
deleted file mode 100644
index ca9ac66e..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/bool/LogicBinaryOperator.java
+++ /dev/null
@@ -1,17 +0,0 @@
-package tools.refinery.store.query.term.bool;
-
-public enum LogicBinaryOperator {
-        AND("&&"),
-        OR("||"),
-        XOR("^^");
-
-        private final String text;
-
-        LogicBinaryOperator(String text) {
-                this.text = text;
-        }
-
-        public String formatString(String left, String right) {
-                return "(%s) %s (%s)".formatted(left, text, right);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/ComparisonTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/ComparisonTerm.java
new file mode 100644
index 00000000..5ca5a0a1
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/ComparisonTerm.java
@@ -0,0 +1,19 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.comparable;
+
+import tools.refinery.store.query.term.BinaryTerm;
+import tools.refinery.store.query.term.Term;
+
+public abstract class ComparisonTerm<T> extends BinaryTerm<Boolean, T, T> {
+        protected ComparisonTerm(Class<T> argumentType, Term<T> left, Term<T> right) {
+                super(Boolean.class, argumentType, argumentType, left, right);
+        }
+
+        public Class<T> getArgumentType() {
+                return getLeftType();
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/EqTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/EqTerm.java
new file mode 100644
index 00000000..b8cf36f8
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/EqTerm.java
@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.comparable;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class EqTerm<T> extends ComparisonTerm<T> {
+        public EqTerm(Class<T> argumentType, Term<T> left, Term<T> right) {
+                super(argumentType, left, right);
+        }
+
+        @Override
+        protected Boolean doEvaluate(T leftValue, T rightValue) {
+                return leftValue.equals(rightValue);
+        }
+
+        @Override
+        public Term<Boolean> doSubstitute(Substitution substitution, Term<T> substitutedLeft, Term<T> substitutedRight) {
+                return new EqTerm<>(getArgumentType(), substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        public String toString() {
+                return "(%s == %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/GreaterEqTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/GreaterEqTerm.java
new file mode 100644
index 00000000..b109eb1a
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/GreaterEqTerm.java
@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.comparable;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class GreaterEqTerm<T extends Comparable<T>> extends ComparisonTerm<T> {
+        public GreaterEqTerm(Class<T> argumentType, Term<T> left, Term<T> right) {
+                super(argumentType, left, right);
+        }
+
+        @Override
+        protected Boolean doEvaluate(T leftValue, T rightValue) {
+                return leftValue.compareTo(rightValue) >= 0;
+        }
+
+        @Override
+        public Term<Boolean> doSubstitute(Substitution substitution, Term<T> substitutedLeft, Term<T> substitutedRight) {
+                return new GreaterEqTerm<>(getArgumentType(), substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        public String toString() {
+                return "(%s >= %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/GreaterTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/GreaterTerm.java
new file mode 100644
index 00000000..1b67f8b5
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/GreaterTerm.java
@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.comparable;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class GreaterTerm<T extends Comparable<T>> extends ComparisonTerm<T> {
+        public GreaterTerm(Class<T> argumentType, Term<T> left, Term<T> right) {
+                super(argumentType, left, right);
+        }
+
+        @Override
+        protected Boolean doEvaluate(T leftValue, T rightValue) {
+                return leftValue.compareTo(rightValue) > 0;
+        }
+
+        @Override
+        public Term<Boolean> doSubstitute(Substitution substitution, Term<T> substitutedLeft, Term<T> substitutedRight) {
+                return new GreaterTerm<>(getArgumentType(), substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        public String toString() {
+                return "(%s > %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/LessEqTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/LessEqTerm.java
new file mode 100644
index 00000000..1b34535f
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/LessEqTerm.java
@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.comparable;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class LessEqTerm<T extends Comparable<T>> extends ComparisonTerm<T> {
+        public LessEqTerm(Class<T> argumentType, Term<T> left, Term<T> right) {
+                super(argumentType, left, right);
+        }
+
+        @Override
+        protected Boolean doEvaluate(T leftValue, T rightValue) {
+                return leftValue.compareTo(rightValue) <= 0;
+        }
+
+        @Override
+        public Term<Boolean> doSubstitute(Substitution substitution, Term<T> substitutedLeft, Term<T> substitutedRight) {
+                return new LessEqTerm<>(getArgumentType(), substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        public String toString() {
+                return "(%s <= %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/LessTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/LessTerm.java
new file mode 100644
index 00000000..44e70902
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/LessTerm.java
@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.comparable;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class LessTerm<T extends Comparable<T>> extends ComparisonTerm<T> {
+        public LessTerm(Class<T> argumentType, Term<T> left, Term<T> right) {
+                super(argumentType, left, right);
+        }
+
+        @Override
+        protected Boolean doEvaluate(T leftValue, T rightValue) {
+                return leftValue.compareTo(rightValue) < 0;
+        }
+
+        @Override
+        public Term<Boolean> doSubstitute(Substitution substitution, Term<T> substitutedLeft, Term<T> substitutedRight) {
+                return new LessTerm<>(getArgumentType(), substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        public String toString() {
+                return "(%s < %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/NotEqTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/NotEqTerm.java
new file mode 100644
index 00000000..1f9734c4
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/comparable/NotEqTerm.java
@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.comparable;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class NotEqTerm<T> extends ComparisonTerm<T> {
+        public NotEqTerm(Class<T> argumentType, Term<T> left, Term<T> right) {
+                super(argumentType, left, right);
+        }
+
+        @Override
+        protected Boolean doEvaluate(T leftValue, T rightValue) {
+                return !leftValue.equals(rightValue);
+        }
+
+        @Override
+        public Term<Boolean> doSubstitute(Substitution substitution, Term<T> substitutedLeft, Term<T> substitutedRight) {
+                return new NotEqTerm<>(getArgumentType(), substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        public String toString() {
+                return "(%s != %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntAddTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntAddTerm.java
new file mode 100644
index 00000000..dbea3efc
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntAddTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.int_;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class IntAddTerm extends IntBinaryTerm {
+        public IntAddTerm(Term<Integer> left, Term<Integer> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Integer> doSubstitute(Substitution substitution, Term<Integer> substitutedLeft,
+                                                                          Term<Integer> substitutedRight) {
+                return new IntAddTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Integer doEvaluate(Integer leftValue, Integer rightValue) {
+                return leftValue + rightValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(%s + %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntArithmeticBinaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntArithmeticBinaryTerm.java
deleted file mode 100644
index 32e41718..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntArithmeticBinaryTerm.java
+++ /dev/null
@@ -1,48 +0,0 @@
-package tools.refinery.store.query.term.int_;
-
-import tools.refinery.store.query.substitution.Substitution;
-import tools.refinery.store.query.term.ArithmeticBinaryOperator;
-import tools.refinery.store.query.term.ArithmeticBinaryTerm;
-import tools.refinery.store.query.term.Term;
-
-public class IntArithmeticBinaryTerm extends ArithmeticBinaryTerm<Integer> {
-        public IntArithmeticBinaryTerm(ArithmeticBinaryOperator operator, Term<Integer> left, Term<Integer> right) {
-                super(operator, left, right);
-        }
-
-        @Override
-        public Class<Integer> getType() {
-                return Integer.class;
-        }
-
-        @Override
-        public Term<Integer> doSubstitute(Substitution substitution, Term<Integer> substitutedLeft,
-                                                                          Term<Integer> substitutedRight) {
-                return new IntArithmeticBinaryTerm(getOperator(), substitutedLeft, substitutedRight);
-        }
-
-        @Override
-        protected Integer doEvaluate(Integer leftValue, Integer rightValue) {
-                return switch (getOperator()) {
-                        case ADD -> leftValue + rightValue;
-                        case SUB -> leftValue - rightValue;
-                        case MUL -> leftValue * rightValue;
-                        case DIV -> rightValue == 0 ? null : leftValue / rightValue;
-                        case POW -> rightValue < 0 ? null : power(leftValue, rightValue);
-                        case MIN -> Math.min(leftValue, rightValue);
-                        case MAX -> Math.max(leftValue, rightValue);
-                };
-        }
-
-        private static int power(int base, int exponent) {
-                int accum = 1;
-                while (exponent > 0) {
-                        if (exponent % 2 == 1) {
-                                accum = accum * base;
-                        }
-                        base = base * base;
-                        exponent = exponent / 2;
-                }
-                return accum;
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntArithmeticUnaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntArithmeticUnaryTerm.java
deleted file mode 100644
index 1e769259..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntArithmeticUnaryTerm.java
+++ /dev/null
@@ -1,30 +0,0 @@
-package tools.refinery.store.query.term.int_;
-
-import tools.refinery.store.query.substitution.Substitution;
-import tools.refinery.store.query.term.Term;
-import tools.refinery.store.query.term.ArithmeticUnaryOperator;
-import tools.refinery.store.query.term.ArithmeticUnaryTerm;
-
-public class IntArithmeticUnaryTerm extends ArithmeticUnaryTerm<Integer> {
-        public IntArithmeticUnaryTerm(ArithmeticUnaryOperator operation, Term<Integer> body) {
-                super(operation, body);
-        }
-
-        @Override
-        public Class<Integer> getType() {
-                return Integer.class;
-        }
-
-        @Override
-        protected Term<Integer> doSubstitute(Substitution substitution, Term<Integer> substitutedBody) {
-                return new IntArithmeticUnaryTerm(getOperator(), substitutedBody);
-        }
-
-        @Override
-        protected Integer doEvaluate(Integer bodyValue) {
-                return switch(getOperator()) {
-                        case PLUS -> bodyValue;
-                        case MINUS -> -bodyValue;
-                };
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntBinaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntBinaryTerm.java
new file mode 100644
index 00000000..27ced4e4
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntBinaryTerm.java
@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.int_;
+
+import tools.refinery.store.query.term.BinaryTerm;
+import tools.refinery.store.query.term.Term;
+
+public abstract class IntBinaryTerm extends BinaryTerm<Integer, Integer, Integer> {
+        protected IntBinaryTerm(Term<Integer> left, Term<Integer> right) {
+                super(Integer.class, Integer.class, Integer.class, left, right);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntComparisonTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntComparisonTerm.java
deleted file mode 100644
index 322d2b80..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntComparisonTerm.java
+++ /dev/null
@@ -1,34 +0,0 @@
-package tools.refinery.store.query.term.int_;
-import tools.refinery.store.query.substitution.Substitution;
-import tools.refinery.store.query.term.ComparisonOperator;
-import tools.refinery.store.query.term.ComparisonTerm;
-import tools.refinery.store.query.term.Term;
-
-public class IntComparisonTerm extends ComparisonTerm<Integer> {
-        public IntComparisonTerm(ComparisonOperator operator, Term<Integer> left, Term<Integer> right) {
-                super(operator, left, right);
-        }
-
-        @Override
-        public Class<Integer> getOperandType() {
-                return Integer.class;
-        }
-
-        @Override
-        public Term<Boolean> doSubstitute(Substitution substitution, Term<Integer> substitutedLeft,
-                                                                          Term<Integer> substitutedRight) {
-                return new IntComparisonTerm(getOperator(), substitutedLeft, substitutedRight);
-        }
-
-        @Override
-        protected Boolean doEvaluate(Integer leftValue, Integer rightValue) {
-                return switch (getOperator()) {
-                        case EQ -> leftValue.equals(rightValue);
-                        case NOT_EQ -> !leftValue.equals(rightValue);
-                        case LESS -> leftValue < rightValue;
-                        case LESS_EQ -> leftValue <= rightValue;
-                        case GREATER -> leftValue > rightValue;
-                        case GREATER_EQ -> leftValue >= rightValue;
-                };
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntDivTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntDivTerm.java
new file mode 100644
index 00000000..2a35058c
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntDivTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.int_;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class IntDivTerm extends IntBinaryTerm {
+        public IntDivTerm(Term<Integer> left, Term<Integer> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Integer> doSubstitute(Substitution substitution, Term<Integer> substitutedLeft,
+                                                                          Term<Integer> substitutedRight) {
+                return new IntDivTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Integer doEvaluate(Integer leftValue, Integer rightValue) {
+                return rightValue == 0 ? null : leftValue / rightValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(%s / %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntExtremeValueAggregator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntExtremeValueAggregator.java
deleted file mode 100644
index d5a6add0..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntExtremeValueAggregator.java
+++ /dev/null
@@ -1,17 +0,0 @@
-package tools.refinery.store.query.term.int_;
-
-import tools.refinery.store.query.term.ExtremeValueAggregator;
-
-import java.util.Comparator;
-
-public final class IntExtremeValueAggregator {
-        public static final ExtremeValueAggregator<Integer> MINIMUM = new ExtremeValueAggregator<>(Integer.class,
-                        Integer.MAX_VALUE);
-
-        public static final ExtremeValueAggregator<Integer> MAXIMUM = new ExtremeValueAggregator<>(Integer.class,
-                        Integer.MIN_VALUE, Comparator.reverseOrder());
-
-        private IntExtremeValueAggregator() {
-                throw new IllegalStateException("This is a static utility class and should not be instantiated directly");
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntMaxTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntMaxTerm.java
new file mode 100644
index 00000000..f81fc509
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntMaxTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.int_;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class IntMaxTerm extends IntBinaryTerm {
+        public IntMaxTerm(Term<Integer> left, Term<Integer> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Integer> doSubstitute(Substitution substitution, Term<Integer> substitutedLeft,
+                                                                          Term<Integer> substitutedRight) {
+                return new IntMaxTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Integer doEvaluate(Integer leftValue, Integer rightValue) {
+                return Math.max(rightValue, leftValue);
+        }
+
+        @Override
+        public String toString() {
+                return "max(%s, %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntMinTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntMinTerm.java
new file mode 100644
index 00000000..89182e26
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntMinTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.int_;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class IntMinTerm extends IntBinaryTerm {
+        public IntMinTerm(Term<Integer> left, Term<Integer> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Integer> doSubstitute(Substitution substitution, Term<Integer> substitutedLeft,
+                                                                          Term<Integer> substitutedRight) {
+                return new IntMinTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Integer doEvaluate(Integer leftValue, Integer rightValue) {
+                return Math.min(rightValue, leftValue);
+        }
+
+        @Override
+        public String toString() {
+                return "min(%s, %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntMinusTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntMinusTerm.java
new file mode 100644
index 00000000..709aa5ba
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntMinusTerm.java
@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.int_;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class IntMinusTerm extends IntUnaryTerm {
+        public IntMinusTerm(Term<Integer> body) {
+                super(body);
+        }
+
+        @Override
+        protected Term<Integer> doSubstitute(Substitution substitution, Term<Integer> substitutedBody) {
+                return new IntMinusTerm(substitutedBody);
+        }
+
+        @Override
+        protected Integer doEvaluate(Integer bodyValue) {
+                return -bodyValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(-%s)".formatted(getBody());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntMulTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntMulTerm.java
new file mode 100644
index 00000000..89d4c5f4
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntMulTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.int_;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class IntMulTerm extends IntBinaryTerm {
+        public IntMulTerm(Term<Integer> left, Term<Integer> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Integer> doSubstitute(Substitution substitution, Term<Integer> substitutedLeft,
+                                                                          Term<Integer> substitutedRight) {
+                return new IntMulTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Integer doEvaluate(Integer leftValue, Integer rightValue) {
+                return leftValue * rightValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(%s * %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntPlusTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntPlusTerm.java
new file mode 100644
index 00000000..aef83bb4
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntPlusTerm.java
@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.int_;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class IntPlusTerm extends IntUnaryTerm {
+        public IntPlusTerm(Term<Integer> body) {
+                super(body);
+        }
+
+        @Override
+        protected Term<Integer> doSubstitute(Substitution substitution, Term<Integer> substitutedBody) {
+                return new IntPlusTerm(substitutedBody);
+        }
+
+        @Override
+        protected Integer doEvaluate(Integer bodyValue) {
+                return bodyValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(+%s)".formatted(getBody());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntPowTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntPowTerm.java
new file mode 100644
index 00000000..d5af97a1
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntPowTerm.java
@@ -0,0 +1,43 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.int_;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class IntPowTerm extends IntBinaryTerm {
+        public IntPowTerm(Term<Integer> left, Term<Integer> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Integer> doSubstitute(Substitution substitution, Term<Integer> substitutedLeft,
+                                                                          Term<Integer> substitutedRight) {
+                return new IntPowTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Integer doEvaluate(Integer leftValue, Integer rightValue) {
+                return rightValue < 0 ? null : power(leftValue, rightValue);
+        }
+
+        private static int power(int base, int exponent) {
+                int accum = 1;
+                while (exponent > 0) {
+                        if (exponent % 2 == 1) {
+                                accum = accum * base;
+                        }
+                        base = base * base;
+                        exponent = exponent / 2;
+                }
+                return accum;
+        }
+
+        @Override
+        public String toString() {
+                return "(%s ** %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntSubTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntSubTerm.java
new file mode 100644
index 00000000..2c27afb1
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntSubTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.int_;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class IntSubTerm extends IntBinaryTerm {
+        public IntSubTerm(Term<Integer> left, Term<Integer> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Integer> doSubstitute(Substitution substitution, Term<Integer> substitutedLeft,
+                                                                          Term<Integer> substitutedRight) {
+                return new IntSubTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Integer doEvaluate(Integer leftValue, Integer rightValue) {
+                return leftValue - rightValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(%s - %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntSumAggregator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntSumAggregator.java
index 65024f52..cd718c53 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntSumAggregator.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntSumAggregator.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term.int_;
 
 import tools.refinery.store.query.term.StatelessAggregator;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntTerms.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntTerms.java
index 86594deb..acb98b94 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntTerms.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntTerms.java
@@ -1,81 +1,94 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term.int_;
 
-import tools.refinery.store.query.term.*;
+import tools.refinery.store.query.term.Aggregator;
+import tools.refinery.store.query.term.ConstantTerm;
+import tools.refinery.store.query.term.ExtremeValueAggregator;
+import tools.refinery.store.query.term.Term;
+import tools.refinery.store.query.term.comparable.*;
+
+import java.util.Comparator;
 
 public final class IntTerms {
         public static final Aggregator<Integer, Integer> INT_SUM = IntSumAggregator.INSTANCE;
-        public static final Aggregator<Integer, Integer> INT_MIN = IntExtremeValueAggregator.MINIMUM;
-        public static final Aggregator<Integer, Integer> INT_MAX = IntExtremeValueAggregator.MAXIMUM;
+        public static final Aggregator<Integer, Integer> INT_MIN = new ExtremeValueAggregator<>(Integer.class,
+                        Integer.MAX_VALUE);
+        public static final Aggregator<Integer, Integer> INT_MAX = new ExtremeValueAggregator<>(Integer.class,
+                        Integer.MIN_VALUE, Comparator.reverseOrder());
 
         private IntTerms() {
                 throw new IllegalArgumentException("This is a static utility class and should not be instantiated directly");
         }
 
-        public static ConstantTerm<Integer> constant(int value) {
+        public static Term<Integer> constant(Integer value) {
                 return new ConstantTerm<>(Integer.class, value);
         }
 
-        public static IntArithmeticUnaryTerm plus(Term<Integer> body) {
-                return new IntArithmeticUnaryTerm(ArithmeticUnaryOperator.PLUS, body);
+        public static Term<Integer> plus(Term<Integer> body) {
+                return new IntPlusTerm(body);
         }
 
-        public static IntArithmeticUnaryTerm minus(Term<Integer> body) {
-                return new IntArithmeticUnaryTerm(ArithmeticUnaryOperator.MINUS, body);
+        public static Term<Integer> minus(Term<Integer> body) {
+                return new IntMinusTerm(body);
         }
 
-        public static IntArithmeticBinaryTerm add(Term<Integer> left, Term<Integer> right) {
-                return new IntArithmeticBinaryTerm(ArithmeticBinaryOperator.ADD, left, right);
+        public static Term<Integer> add(Term<Integer> left, Term<Integer> right) {
+                return new IntAddTerm(left, right);
         }
 
-        public static IntArithmeticBinaryTerm sub(Term<Integer> left, Term<Integer> right) {
-                return new IntArithmeticBinaryTerm(ArithmeticBinaryOperator.SUB, left, right);
+        public static Term<Integer> sub(Term<Integer> left, Term<Integer> right) {
+                return new IntSubTerm(left, right);
         }
 
-        public static IntArithmeticBinaryTerm mul(Term<Integer> left, Term<Integer> right) {
-                return new IntArithmeticBinaryTerm(ArithmeticBinaryOperator.MUL, left, right);
+        public static Term<Integer> mul(Term<Integer> left, Term<Integer> right) {
+                return new IntMulTerm(left, right);
         }
 
-        public static IntArithmeticBinaryTerm div(Term<Integer> left, Term<Integer> right) {
-                return new IntArithmeticBinaryTerm(ArithmeticBinaryOperator.DIV, left, right);
+        public static Term<Integer> div(Term<Integer> left, Term<Integer> right) {
+                return new IntDivTerm(left, right);
         }
 
-        public static IntArithmeticBinaryTerm pow(Term<Integer> left, Term<Integer> right) {
-                return new IntArithmeticBinaryTerm(ArithmeticBinaryOperator.POW, left, right);
+        public static Term<Integer> pow(Term<Integer> left, Term<Integer> right) {
+                return new IntPowTerm(left, right);
         }
 
-        public static IntArithmeticBinaryTerm min(Term<Integer> left, Term<Integer> right) {
-                return new IntArithmeticBinaryTerm(ArithmeticBinaryOperator.MIN, left, right);
+        public static Term<Integer> min(Term<Integer> left, Term<Integer> right) {
+                return new IntMinTerm(left, right);
         }
 
-        public static IntArithmeticBinaryTerm max(Term<Integer> left, Term<Integer> right) {
-                return new IntArithmeticBinaryTerm(ArithmeticBinaryOperator.MAX, left, right);
+        public static Term<Integer> max(Term<Integer> left, Term<Integer> right) {
+                return new IntMaxTerm(left, right);
         }
 
-        public static IntComparisonTerm eq(Term<Integer> left, Term<Integer> right) {
-                return new IntComparisonTerm(ComparisonOperator.EQ, left, right);
+        public static Term<Boolean> eq(Term<Integer> left, Term<Integer> right) {
+                return new EqTerm<>(Integer.class, left, right);
         }
 
-        public static IntComparisonTerm notEq(Term<Integer> left, Term<Integer> right) {
-                return new IntComparisonTerm(ComparisonOperator.NOT_EQ, left, right);
+        public static Term<Boolean> notEq(Term<Integer> left, Term<Integer> right) {
+                return new NotEqTerm<>(Integer.class, left, right);
         }
 
-        public static IntComparisonTerm less(Term<Integer> left, Term<Integer> right) {
-                return new IntComparisonTerm(ComparisonOperator.LESS, left, right);
+        public static Term<Boolean> less(Term<Integer> left, Term<Integer> right) {
+                return new LessTerm<>(Integer.class, left, right);
         }
 
-        public static IntComparisonTerm lessEq(Term<Integer> left, Term<Integer> right) {
-                return new IntComparisonTerm(ComparisonOperator.LESS_EQ, left, right);
+        public static Term<Boolean> lessEq(Term<Integer> left, Term<Integer> right) {
+                return new LessEqTerm<>(Integer.class, left, right);
         }
 
-        public static IntComparisonTerm greater(Term<Integer> left, Term<Integer> right) {
-                return new IntComparisonTerm(ComparisonOperator.GREATER, left, right);
+        public static Term<Boolean> greater(Term<Integer> left, Term<Integer> right) {
+                return new GreaterTerm<>(Integer.class, left, right);
         }
 
-        public static IntComparisonTerm greaterEq(Term<Integer> left, Term<Integer> right) {
-                return new IntComparisonTerm(ComparisonOperator.GREATER_EQ, left, right);
+        public static Term<Boolean> greaterEq(Term<Integer> left, Term<Integer> right) {
+                return new GreaterEqTerm<>(Integer.class, left, right);
         }
 
-        public static RealToIntTerm asInt(Term<Double> body) {
+        public static Term<Integer> asInt(Term<Double> body) {
                 return new RealToIntTerm(body);
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntUnaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntUnaryTerm.java
new file mode 100644
index 00000000..49b4c647
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/IntUnaryTerm.java
@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.int_;
+
+import tools.refinery.store.query.term.Term;
+import tools.refinery.store.query.term.UnaryTerm;
+
+public abstract class IntUnaryTerm extends UnaryTerm<Integer, Integer> {
+        protected IntUnaryTerm(Term<Integer> body) {
+                super(Integer.class, Integer.class, body);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/RealToIntTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/RealToIntTerm.java
index 53875ddc..7d383562 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/RealToIntTerm.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/int_/RealToIntTerm.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term.int_;
 
 import tools.refinery.store.query.substitution.Substitution;
@@ -6,22 +11,12 @@ import tools.refinery.store.query.term.UnaryTerm;
 
 public class RealToIntTerm extends UnaryTerm<Integer, Double> {
         protected RealToIntTerm(Term<Double> body) {
-                super(body);
-        }
-
-        @Override
-        public Class<Integer> getType() {
-                return Integer.class;
-        }
-
-        @Override
-        public Class<Double> getBodyType() {
-                return Double.class;
+                super(Integer.class, Double.class, body);
         }
 
         @Override
         protected Integer doEvaluate(Double bodyValue) {
-                return bodyValue.intValue();
+                return bodyValue.isNaN() ? null : bodyValue.intValue();
         }
 
         @Override
@@ -31,6 +26,6 @@ public class RealToIntTerm extends UnaryTerm<Integer, Double> {
 
         @Override
         public String toString() {
-                return "(%s) as int".formatted(getBody());
+                return "(%s as int)".formatted(getBody());
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/IntToRealTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/IntToRealTerm.java
index 55590824..2f53117a 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/IntToRealTerm.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/IntToRealTerm.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term.real;
 
 import tools.refinery.store.query.substitution.Substitution;
@@ -6,17 +11,7 @@ import tools.refinery.store.query.term.UnaryTerm;
 
 public class IntToRealTerm extends UnaryTerm<Double, Integer> {
         protected IntToRealTerm(Term<Integer> body) {
-                super(body);
-        }
-
-        @Override
-        public Class<Double> getType() {
-                return Double.class;
-        }
-
-        @Override
-        public Class<Integer> getBodyType() {
-                return Integer.class;
+                super(Double.class, Integer.class, body);
         }
 
         @Override
@@ -31,6 +26,6 @@ public class IntToRealTerm extends UnaryTerm<Double, Integer> {
 
         @Override
         public String toString() {
-                return "(%s) as real".formatted(getBody());
+                return "(%s as real)".formatted(getBody());
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealAddTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealAddTerm.java
new file mode 100644
index 00000000..33fc9e41
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealAddTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.real;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class RealAddTerm extends RealBinaryTerm {
+        public RealAddTerm(Term<Double> left, Term<Double> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Double> doSubstitute(Substitution substitution, Term<Double> substitutedLeft,
+                                                                         Term<Double> substitutedRight) {
+                return new RealAddTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Double doEvaluate(Double leftValue, Double rightValue) {
+                return leftValue + rightValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(%s + %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealArithmeticBinaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealArithmeticBinaryTerm.java
deleted file mode 100644
index 57bcbe5e..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealArithmeticBinaryTerm.java
+++ /dev/null
@@ -1,36 +0,0 @@
-package tools.refinery.store.query.term.real;
-
-import tools.refinery.store.query.substitution.Substitution;
-import tools.refinery.store.query.term.ArithmeticBinaryOperator;
-import tools.refinery.store.query.term.ArithmeticBinaryTerm;
-import tools.refinery.store.query.term.Term;
-
-public class RealArithmeticBinaryTerm extends ArithmeticBinaryTerm<Double> {
-        public RealArithmeticBinaryTerm(ArithmeticBinaryOperator operator, Term<Double> left, Term<Double> right) {
-                super(operator, left, right);
-        }
-
-        @Override
-        public Class<Double> getType() {
-                return Double.class;
-        }
-
-        @Override
-        public Term<Double> doSubstitute(Substitution substitution, Term<Double> substitutedLeft,
-                                                                         Term<Double> substitutedRight) {
-                return new RealArithmeticBinaryTerm(getOperator(), substitutedLeft, substitutedRight);
-        }
-
-        @Override
-        protected Double doEvaluate(Double leftValue, Double rightValue) {
-                return switch (getOperator()) {
-                        case ADD -> leftValue + rightValue;
-                        case SUB -> leftValue - rightValue;
-                        case MUL -> leftValue * rightValue;
-                        case DIV -> leftValue / rightValue;
-                        case POW -> Math.pow(leftValue, rightValue);
-                        case MIN -> Math.min(leftValue, rightValue);
-                        case MAX -> Math.max(leftValue, rightValue);
-                };
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealArithmeticUnaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealArithmeticUnaryTerm.java
deleted file mode 100644
index 632e68bf..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealArithmeticUnaryTerm.java
+++ /dev/null
@@ -1,30 +0,0 @@
-package tools.refinery.store.query.term.real;
-
-import tools.refinery.store.query.substitution.Substitution;
-import tools.refinery.store.query.term.ArithmeticUnaryOperator;
-import tools.refinery.store.query.term.ArithmeticUnaryTerm;
-import tools.refinery.store.query.term.Term;
-
-public class RealArithmeticUnaryTerm extends ArithmeticUnaryTerm<Double> {
-        public RealArithmeticUnaryTerm(ArithmeticUnaryOperator operation, Term<Double> body) {
-                super(operation, body);
-        }
-
-        @Override
-        public Class<Double> getType() {
-                return Double.class;
-        }
-
-        @Override
-        protected Term<Double> doSubstitute(Substitution substitution, Term<Double> substitutedBody) {
-                return new RealArithmeticUnaryTerm(getOperator(), substitutedBody);
-        }
-
-        @Override
-        protected Double doEvaluate(Double bodyValue) {
-                return switch(getOperator()) {
-                        case PLUS -> bodyValue;
-                        case MINUS -> -bodyValue;
-                };
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealBinaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealBinaryTerm.java
new file mode 100644
index 00000000..000f3623
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealBinaryTerm.java
@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.real;
+
+import tools.refinery.store.query.term.BinaryTerm;
+import tools.refinery.store.query.term.Term;
+
+public abstract class RealBinaryTerm extends BinaryTerm<Double, Double, Double> {
+        protected RealBinaryTerm(Term<Double> left, Term<Double> right) {
+                super(Double.class, Double.class, Double.class, left, right);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealComparisonTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealComparisonTerm.java
deleted file mode 100644
index 75d97adb..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealComparisonTerm.java
+++ /dev/null
@@ -1,35 +0,0 @@
-package tools.refinery.store.query.term.real;
-
-import tools.refinery.store.query.substitution.Substitution;
-import tools.refinery.store.query.term.ComparisonOperator;
-import tools.refinery.store.query.term.ComparisonTerm;
-import tools.refinery.store.query.term.Term;
-
-public class RealComparisonTerm extends ComparisonTerm<Double> {
-        public RealComparisonTerm(ComparisonOperator operator, Term<Double> left, Term<Double> right) {
-                super(operator, left, right);
-        }
-
-        @Override
-        public Class<Double> getOperandType() {
-                return Double.class;
-        }
-
-        @Override
-        public Term<Boolean> doSubstitute(Substitution substitution, Term<Double> substitutedLeft,
-                                                                          Term<Double> substitutedRight) {
-                return new RealComparisonTerm(getOperator(), substitutedLeft, substitutedRight);
-        }
-
-        @Override
-        protected Boolean doEvaluate(Double leftValue, Double rightValue) {
-                return switch (getOperator()) {
-                        case EQ -> leftValue.equals(rightValue);
-                        case NOT_EQ -> !leftValue.equals(rightValue);
-                        case LESS -> leftValue < rightValue;
-                        case LESS_EQ -> leftValue <= rightValue;
-                        case GREATER -> leftValue > rightValue;
-                        case GREATER_EQ -> leftValue >= rightValue;
-                };
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealDivTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealDivTerm.java
new file mode 100644
index 00000000..1e55bf42
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealDivTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.real;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class RealDivTerm extends RealBinaryTerm {
+        public RealDivTerm(Term<Double> left, Term<Double> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Double> doSubstitute(Substitution substitution, Term<Double> substitutedLeft,
+                                                                         Term<Double> substitutedRight) {
+                return new RealDivTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Double doEvaluate(Double leftValue, Double rightValue) {
+                return leftValue / rightValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(%s / %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealExtremeValueAggregator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealExtremeValueAggregator.java
deleted file mode 100644
index 23384530..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealExtremeValueAggregator.java
+++ /dev/null
@@ -1,17 +0,0 @@
-package tools.refinery.store.query.term.real;
-
-import tools.refinery.store.query.term.ExtremeValueAggregator;
-
-import java.util.Comparator;
-
-public final class RealExtremeValueAggregator {
-        public static final ExtremeValueAggregator<Double> MINIMUM = new ExtremeValueAggregator<>(Double.class,
-                        Double.POSITIVE_INFINITY);
-
-        public static final ExtremeValueAggregator<Double> MAXIMUM = new ExtremeValueAggregator<>(Double.class,
-                        Double.NEGATIVE_INFINITY, Comparator.reverseOrder());
-
-        private RealExtremeValueAggregator() {
-                throw new IllegalStateException("This is a static utility class and should not be instantiated directly");
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealMaxTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealMaxTerm.java
new file mode 100644
index 00000000..2a249496
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealMaxTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.real;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class RealMaxTerm extends RealBinaryTerm {
+        public RealMaxTerm(Term<Double> left, Term<Double> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Double> doSubstitute(Substitution substitution, Term<Double> substitutedLeft,
+                                                                         Term<Double> substitutedRight) {
+                return new RealMaxTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Double doEvaluate(Double leftValue, Double rightValue) {
+                return Math.max(leftValue, rightValue);
+        }
+
+        @Override
+        public String toString() {
+                return "max(%s, %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealMinTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealMinTerm.java
new file mode 100644
index 00000000..2eb4cc1e
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealMinTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.real;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class RealMinTerm extends RealBinaryTerm {
+        public RealMinTerm(Term<Double> left, Term<Double> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Double> doSubstitute(Substitution substitution, Term<Double> substitutedLeft,
+                                                                         Term<Double> substitutedRight) {
+                return new RealMinTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Double doEvaluate(Double leftValue, Double rightValue) {
+                return Math.min(leftValue, rightValue);
+        }
+
+        @Override
+        public String toString() {
+                return "min(%s, %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealMinusTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealMinusTerm.java
new file mode 100644
index 00000000..4afec7a1
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealMinusTerm.java
@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.real;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class RealMinusTerm extends RealUnaryTerm {
+        public RealMinusTerm(Term<Double> body) {
+                super(body);
+        }
+
+        @Override
+        protected Term<Double> doSubstitute(Substitution substitution, Term<Double> substitutedBody) {
+                return new RealMinusTerm(substitutedBody);
+        }
+
+        @Override
+        protected Double doEvaluate(Double bodyValue) {
+                return -bodyValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(-%s)".formatted(getBody());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealMulTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealMulTerm.java
new file mode 100644
index 00000000..ec95ac6f
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealMulTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.real;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class RealMulTerm extends RealBinaryTerm {
+        public RealMulTerm(Term<Double> left, Term<Double> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Double> doSubstitute(Substitution substitution, Term<Double> substitutedLeft,
+                                                                         Term<Double> substitutedRight) {
+                return new RealMulTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Double doEvaluate(Double leftValue, Double rightValue) {
+                return leftValue * rightValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(%s * %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealPlusTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealPlusTerm.java
new file mode 100644
index 00000000..64dd2e70
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealPlusTerm.java
@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.real;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class RealPlusTerm extends RealUnaryTerm {
+        public RealPlusTerm(Term<Double> body) {
+                super(body);
+        }
+
+        @Override
+        protected Term<Double> doSubstitute(Substitution substitution, Term<Double> substitutedBody) {
+                return new RealPlusTerm(substitutedBody);
+        }
+
+        @Override
+        protected Double doEvaluate(Double bodyValue) {
+                return bodyValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(+%s)".formatted(getBody());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealPowTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealPowTerm.java
new file mode 100644
index 00000000..11c952ea
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealPowTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.real;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class RealPowTerm extends RealBinaryTerm {
+        public RealPowTerm(Term<Double> left, Term<Double> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Double> doSubstitute(Substitution substitution, Term<Double> substitutedLeft,
+                                                                         Term<Double> substitutedRight) {
+                return new RealPowTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Double doEvaluate(Double leftValue, Double rightValue) {
+                return Math.pow(leftValue, rightValue);
+        }
+
+        @Override
+        public String toString() {
+                return "(%s ** %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealSubTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealSubTerm.java
new file mode 100644
index 00000000..8cc701ed
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealSubTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.real;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+
+public class RealSubTerm extends RealBinaryTerm {
+        public RealSubTerm(Term<Double> left, Term<Double> right) {
+                super(left, right);
+        }
+
+        @Override
+        public Term<Double> doSubstitute(Substitution substitution, Term<Double> substitutedLeft,
+                                                                         Term<Double> substitutedRight) {
+                return new RealSubTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        protected Double doEvaluate(Double leftValue, Double rightValue) {
+                return leftValue - rightValue;
+        }
+
+        @Override
+        public String toString() {
+                return "(%s - %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealSumAggregator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealSumAggregator.java
index d5888664..d21048e9 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealSumAggregator.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealSumAggregator.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term.real;
 
 import tools.refinery.store.query.term.StatefulAggregate;
@@ -14,12 +19,12 @@ public final class RealSumAggregator implements StatefulAggregator<Double, Doubl
 
         @Override
         public Class<Double> getResultType() {
-                return null;
+                return Double.class;
         }
 
         @Override
         public Class<Double> getInputType() {
-                return null;
+                return Double.class;
         }
 
         @Override
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealTerms.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealTerms.java
index a8117842..79220358 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealTerms.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealTerms.java
@@ -1,81 +1,94 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.term.real;
 
-import tools.refinery.store.query.term.*;
+import tools.refinery.store.query.term.Aggregator;
+import tools.refinery.store.query.term.ConstantTerm;
+import tools.refinery.store.query.term.ExtremeValueAggregator;
+import tools.refinery.store.query.term.Term;
+import tools.refinery.store.query.term.comparable.*;
+
+import java.util.Comparator;
 
 public final class RealTerms {
         public static final Aggregator<Double, Double> REAL_SUM = RealSumAggregator.INSTANCE;
-        public static final Aggregator<Double, Double> REAL_MIN = RealExtremeValueAggregator.MINIMUM;
-        public static final Aggregator<Double, Double> REAL_MAX = RealExtremeValueAggregator.MAXIMUM;
+        public static final Aggregator<Double, Double> REAL_MIN = new ExtremeValueAggregator<>(Double.class,
+                        Double.POSITIVE_INFINITY);
+        public static final Aggregator<Double, Double> REAL_MAX = new ExtremeValueAggregator<>(Double.class,
+                        Double.NEGATIVE_INFINITY, Comparator.reverseOrder());
 
         private RealTerms() {
                 throw new IllegalArgumentException("This is a static utility class and should not be instantiated directly");
         }
 
-        public static ConstantTerm<Double> constant(double value) {
+        public static Term<Double> constant(Double value) {
                 return new ConstantTerm<>(Double.class, value);
         }
 
-        public static RealArithmeticUnaryTerm plus(Term<Double> body) {
-                return new RealArithmeticUnaryTerm(ArithmeticUnaryOperator.PLUS, body);
+        public static Term<Double> plus(Term<Double> body) {
+                return new RealPlusTerm(body);
         }
 
-        public static RealArithmeticUnaryTerm minus(Term<Double> body) {
-                return new RealArithmeticUnaryTerm(ArithmeticUnaryOperator.MINUS, body);
+        public static Term<Double> minus(Term<Double> body) {
+                return new RealMinusTerm(body);
         }
 
-        public static RealArithmeticBinaryTerm add(Term<Double> left, Term<Double> right) {
-                return new RealArithmeticBinaryTerm(ArithmeticBinaryOperator.ADD, left, right);
+        public static Term<Double> add(Term<Double> left, Term<Double> right) {
+                return new RealAddTerm(left, right);
         }
 
-        public static RealArithmeticBinaryTerm sub(Term<Double> left, Term<Double> right) {
-                return new RealArithmeticBinaryTerm(ArithmeticBinaryOperator.SUB, left, right);
+        public static Term<Double> sub(Term<Double> left, Term<Double> right) {
+                return new RealSubTerm(left, right);
         }
 
-        public static RealArithmeticBinaryTerm mul(Term<Double> left, Term<Double> right) {
-                return new RealArithmeticBinaryTerm(ArithmeticBinaryOperator.MUL, left, right);
+        public static Term<Double> mul(Term<Double> left, Term<Double> right) {
+                return new RealMulTerm(left, right);
         }
 
-        public static RealArithmeticBinaryTerm div(Term<Double> left, Term<Double> right) {
-                return new RealArithmeticBinaryTerm(ArithmeticBinaryOperator.DIV, left, right);
+        public static Term<Double> div(Term<Double> left, Term<Double> right) {
+                return new RealDivTerm(left, right);
         }
 
-        public static RealArithmeticBinaryTerm pow(Term<Double> left, Term<Double> right) {
-                return new RealArithmeticBinaryTerm(ArithmeticBinaryOperator.POW, left, right);
+        public static Term<Double> pow(Term<Double> left, Term<Double> right) {
+                return new RealPowTerm(left, right);
         }
 
-        public static RealArithmeticBinaryTerm min(Term<Double> left, Term<Double> right) {
-                return new RealArithmeticBinaryTerm(ArithmeticBinaryOperator.MIN, left, right);
+        public static Term<Double> min(Term<Double> left, Term<Double> right) {
+                return new RealMinTerm(left, right);
         }
 
-        public static RealArithmeticBinaryTerm max(Term<Double> left, Term<Double> right) {
-                return new RealArithmeticBinaryTerm(ArithmeticBinaryOperator.MAX, left, right);
+        public static Term<Double> max(Term<Double> left, Term<Double> right) {
+                return new RealMaxTerm(left, right);
         }
 
-        public static RealComparisonTerm eq(Term<Double> left, Term<Double> right) {
-                return new RealComparisonTerm(ComparisonOperator.EQ, left, right);
+        public static Term<Boolean> eq(Term<Double> left, Term<Double> right) {
+                return new EqTerm<>(Double.class, left, right);
         }
 
-        public static RealComparisonTerm notEq(Term<Double> left, Term<Double> right) {
-                return new RealComparisonTerm(ComparisonOperator.NOT_EQ, left, right);
+        public static Term<Boolean> notEq(Term<Double> left, Term<Double> right) {
+                return new NotEqTerm<>(Double.class, left, right);
         }
 
-        public static RealComparisonTerm less(Term<Double> left, Term<Double> right) {
-                return new RealComparisonTerm(ComparisonOperator.LESS, left, right);
+        public static Term<Boolean> less(Term<Double> left, Term<Double> right) {
+                return new LessTerm<>(Double.class, left, right);
         }
 
-        public static RealComparisonTerm lessEq(Term<Double> left, Term<Double> right) {
-                return new RealComparisonTerm(ComparisonOperator.LESS_EQ, left, right);
+        public static Term<Boolean> lessEq(Term<Double> left, Term<Double> right) {
+                return new LessEqTerm<>(Double.class, left, right);
         }
 
-        public static RealComparisonTerm greater(Term<Double> left, Term<Double> right) {
-                return new RealComparisonTerm(ComparisonOperator.GREATER, left, right);
+        public static Term<Boolean> greater(Term<Double> left, Term<Double> right) {
+                return new GreaterTerm<>(Double.class, left, right);
         }
 
-        public static RealComparisonTerm greaterEq(Term<Double> left, Term<Double> right) {
-                return new RealComparisonTerm(ComparisonOperator.GREATER_EQ, left, right);
+        public static Term<Boolean> greaterEq(Term<Double> left, Term<Double> right) {
+                return new GreaterEqTerm<>(Double.class, left, right);
         }
 
-        public static IntToRealTerm asReal(Term<Integer> body) {
+        public static Term<Double> asReal(Term<Integer> body) {
                 return new IntToRealTerm(body);
         }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealUnaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealUnaryTerm.java
new file mode 100644
index 00000000..d41c4ed9
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/real/RealUnaryTerm.java
@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.real;
+
+import tools.refinery.store.query.term.Term;
+import tools.refinery.store.query.term.UnaryTerm;
+
+public abstract class RealUnaryTerm extends UnaryTerm<Double, Double> {
+        protected RealUnaryTerm(Term<Double> body) {
+                super(Double.class, Double.class, body);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityAddTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityAddTerm.java
new file mode 100644
index 00000000..68905f51
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityAddTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.uppercardinality;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+import tools.refinery.store.representation.cardinality.UpperCardinality;
+
+public class UpperCardinalityAddTerm extends UpperCardinalityBinaryTerm {
+        protected UpperCardinalityAddTerm(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                super(left, right);
+        }
+
+        @Override
+        protected UpperCardinality doEvaluate(UpperCardinality leftValue, UpperCardinality rightValue) {
+                return leftValue.add(rightValue);
+        }
+
+        @Override
+        public Term<UpperCardinality> doSubstitute(Substitution substitution, Term<UpperCardinality> substitutedLeft, Term<UpperCardinality> substitutedRight) {
+                return new UpperCardinalityAddTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        public String toString() {
+                return "(%s + %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityBinaryTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityBinaryTerm.java
new file mode 100644
index 00000000..0cf8fe44
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityBinaryTerm.java
@@ -0,0 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.uppercardinality;
+
+import tools.refinery.store.query.term.BinaryTerm;
+import tools.refinery.store.query.term.Term;
+import tools.refinery.store.representation.cardinality.UpperCardinality;
+
+public abstract class UpperCardinalityBinaryTerm extends BinaryTerm<UpperCardinality, UpperCardinality,
+                UpperCardinality> {
+        protected UpperCardinalityBinaryTerm(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                super(UpperCardinality.class, UpperCardinality.class, UpperCardinality.class, left, right);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityMaxTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityMaxTerm.java
new file mode 100644
index 00000000..ff75f64e
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityMaxTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.uppercardinality;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+import tools.refinery.store.representation.cardinality.UpperCardinality;
+
+public class UpperCardinalityMaxTerm extends UpperCardinalityBinaryTerm {
+        protected UpperCardinalityMaxTerm(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                super(left, right);
+        }
+
+        @Override
+        protected UpperCardinality doEvaluate(UpperCardinality leftValue, UpperCardinality rightValue) {
+                return leftValue.max(rightValue);
+        }
+
+        @Override
+        public Term<UpperCardinality> doSubstitute(Substitution substitution, Term<UpperCardinality> substitutedLeft, Term<UpperCardinality> substitutedRight) {
+                return new UpperCardinalityMaxTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        public String toString() {
+                return "max(%s, %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityMinTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityMinTerm.java
new file mode 100644
index 00000000..1e89e9f4
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityMinTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.uppercardinality;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+import tools.refinery.store.representation.cardinality.UpperCardinality;
+
+public class UpperCardinalityMinTerm extends UpperCardinalityBinaryTerm {
+        protected UpperCardinalityMinTerm(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                super(left, right);
+        }
+
+        @Override
+        protected UpperCardinality doEvaluate(UpperCardinality leftValue, UpperCardinality rightValue) {
+                return leftValue.min(rightValue);
+        }
+
+        @Override
+        public Term<UpperCardinality> doSubstitute(Substitution substitution, Term<UpperCardinality> substitutedLeft, Term<UpperCardinality> substitutedRight) {
+                return new UpperCardinalityMinTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        public String toString() {
+                return "min(%s, %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityMulTerm.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityMulTerm.java
new file mode 100644
index 00000000..3b4970f4
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityMulTerm.java
@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.uppercardinality;
+
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.Term;
+import tools.refinery.store.representation.cardinality.UpperCardinality;
+
+public class UpperCardinalityMulTerm extends UpperCardinalityBinaryTerm {
+        protected UpperCardinalityMulTerm(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                super(left, right);
+        }
+
+        @Override
+        protected UpperCardinality doEvaluate(UpperCardinality leftValue, UpperCardinality rightValue) {
+                return leftValue.multiply(rightValue);
+        }
+
+        @Override
+        public Term<UpperCardinality> doSubstitute(Substitution substitution, Term<UpperCardinality> substitutedLeft, Term<UpperCardinality> substitutedRight) {
+                return new UpperCardinalityMulTerm(substitutedLeft, substitutedRight);
+        }
+
+        @Override
+        public String toString() {
+                return "(%s * %s)".formatted(getLeft(), getRight());
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalitySumAggregator.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalitySumAggregator.java
new file mode 100644
index 00000000..5bbd3081
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalitySumAggregator.java
@@ -0,0 +1,86 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.uppercardinality;
+
+import tools.refinery.store.query.term.StatefulAggregate;
+import tools.refinery.store.query.term.StatefulAggregator;
+import tools.refinery.store.representation.cardinality.FiniteUpperCardinality;
+import tools.refinery.store.representation.cardinality.UnboundedUpperCardinality;
+import tools.refinery.store.representation.cardinality.UpperCardinalities;
+import tools.refinery.store.representation.cardinality.UpperCardinality;
+
+public class UpperCardinalitySumAggregator implements StatefulAggregator<UpperCardinality, UpperCardinality> {
+        public static final UpperCardinalitySumAggregator INSTANCE = new UpperCardinalitySumAggregator();
+
+        private UpperCardinalitySumAggregator() {
+        }
+
+        @Override
+        public Class<UpperCardinality> getResultType() {
+                return UpperCardinality.class;
+        }
+
+        @Override
+        public Class<UpperCardinality> getInputType() {
+                return UpperCardinality.class;
+        }
+
+        @Override
+        public StatefulAggregate<UpperCardinality, UpperCardinality> createEmptyAggregate() {
+                return new Aggregate();
+        }
+
+        private static class Aggregate implements StatefulAggregate<UpperCardinality, UpperCardinality> {
+                private int sumFiniteUpperBounds;
+                private int countUnbounded;
+
+                public Aggregate() {
+                        this(0, 0);
+                }
+
+                private Aggregate(int sumFiniteUpperBounds, int countUnbounded) {
+                        this.sumFiniteUpperBounds = sumFiniteUpperBounds;
+                        this.countUnbounded = countUnbounded;
+                }
+
+                @Override
+                public void add(UpperCardinality value) {
+                        if (value instanceof FiniteUpperCardinality finiteUpperCardinality) {
+                                sumFiniteUpperBounds += finiteUpperCardinality.finiteUpperBound();
+                        } else if (value instanceof UnboundedUpperCardinality) {
+                                countUnbounded += 1;
+                        } else {
+                                throw new IllegalArgumentException("Unknown UpperCardinality: " + value);
+                        }
+                }
+
+                @Override
+                public void remove(UpperCardinality value) {
+                        if (value instanceof FiniteUpperCardinality finiteUpperCardinality) {
+                                sumFiniteUpperBounds -= finiteUpperCardinality.finiteUpperBound();
+                        } else if (value instanceof UnboundedUpperCardinality) {
+                                countUnbounded -= 1;
+                        } else {
+                                throw new IllegalArgumentException("Unknown UpperCardinality: " + value);
+                        }
+                }
+
+                @Override
+                public UpperCardinality getResult() {
+                        return countUnbounded > 0 ? UpperCardinalities.UNBOUNDED : UpperCardinalities.valueOf(sumFiniteUpperBounds);
+                }
+
+                @Override
+                public boolean isEmpty() {
+                        return sumFiniteUpperBounds == 0 && countUnbounded == 0;
+                }
+
+                @Override
+                public StatefulAggregate<UpperCardinality, UpperCardinality> deepCopy() {
+                        return new Aggregate(sumFiniteUpperBounds, countUnbounded);
+                }
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityTerms.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityTerms.java
new file mode 100644
index 00000000..13914f2d
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityTerms.java
@@ -0,0 +1,73 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.uppercardinality;
+
+import tools.refinery.store.query.term.Aggregator;
+import tools.refinery.store.query.term.ConstantTerm;
+import tools.refinery.store.query.term.ExtremeValueAggregator;
+import tools.refinery.store.query.term.Term;
+import tools.refinery.store.query.term.comparable.*;
+import tools.refinery.store.representation.cardinality.UpperCardinalities;
+import tools.refinery.store.representation.cardinality.UpperCardinality;
+
+import java.util.Comparator;
+
+public final class UpperCardinalityTerms {
+        public static final Aggregator<UpperCardinality, UpperCardinality> UPPER_CARDINALITY_SUM =
+                        UpperCardinalitySumAggregator.INSTANCE;
+        public static final Aggregator<UpperCardinality, UpperCardinality> UPPER_CARDINALITY_MIN =
+                        new ExtremeValueAggregator<>(UpperCardinality.class, UpperCardinalities.UNBOUNDED);
+        public static final Aggregator<UpperCardinality, UpperCardinality> UPPER_CARDINALITY_MAX =
+                        new ExtremeValueAggregator<>(UpperCardinality.class, UpperCardinalities.ZERO, Comparator.reverseOrder());
+
+        private UpperCardinalityTerms() {
+                throw new IllegalStateException("This is a static utility class and should not be instantiated directly");
+        }
+
+        public static Term<UpperCardinality> constant(UpperCardinality value) {
+                return new ConstantTerm<>(UpperCardinality.class, value);
+        }
+
+        public static Term<UpperCardinality> add(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                return new UpperCardinalityAddTerm(left, right);
+        }
+
+        public static Term<UpperCardinality> mul(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                return new UpperCardinalityMulTerm(left, right);
+        }
+
+        public static Term<UpperCardinality> min(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                return new UpperCardinalityMinTerm(left, right);
+        }
+
+        public static Term<UpperCardinality> max(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                return new UpperCardinalityMaxTerm(left, right);
+        }
+
+        public static Term<Boolean> eq(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                return new EqTerm<>(UpperCardinality.class, left, right);
+        }
+
+        public static Term<Boolean> notEq(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                return new NotEqTerm<>(UpperCardinality.class, left, right);
+        }
+
+        public static Term<Boolean> less(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                return new LessTerm<>(UpperCardinality.class, left, right);
+        }
+
+        public static Term<Boolean> lessEq(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                return new LessEqTerm<>(UpperCardinality.class, left, right);
+        }
+
+        public static Term<Boolean> greater(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                return new GreaterTerm<>(UpperCardinality.class, left, right);
+        }
+
+        public static Term<Boolean> greaterEq(Term<UpperCardinality> left, Term<UpperCardinality> right) {
+                return new GreaterEqTerm<>(UpperCardinality.class, left, right);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/MapBasedValuation.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/MapBasedValuation.java
new file mode 100644
index 00000000..261ceaa5
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/MapBasedValuation.java
@@ -0,0 +1,22 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.valuation;
+
+import tools.refinery.store.query.term.AnyDataVariable;
+import tools.refinery.store.query.term.DataVariable;
+
+import java.util.Map;
+
+record MapBasedValuation(Map<AnyDataVariable, Object> values) implements Valuation {
+        @Override
+        public <T> T getValue(DataVariable<T> variable) {
+                if (!values.containsKey(variable)) {
+                        throw new IllegalArgumentException("No value for variable %s".formatted(variable));
+                }
+                var value = values.get(variable);
+                return variable.getType().cast(value);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/RestrictedValuation.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/RestrictedValuation.java
index fb512d88..fc8406aa 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/RestrictedValuation.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/RestrictedValuation.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.valuation;
 
 import tools.refinery.store.query.term.AnyDataVariable;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/SubstitutedValuation.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/SubstitutedValuation.java
index 8e79663c..1c14112c 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/SubstitutedValuation.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/SubstitutedValuation.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.valuation;
 
 import tools.refinery.store.query.substitution.Substitution;
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/Valuation.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/Valuation.java
index 3ba9a6b8..1588e957 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/Valuation.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/Valuation.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.valuation;
 
 import org.jetbrains.annotations.Nullable;
@@ -5,6 +10,7 @@ import tools.refinery.store.query.substitution.Substitution;
 import tools.refinery.store.query.term.AnyDataVariable;
 import tools.refinery.store.query.term.DataVariable;
 
+import java.util.Map;
 import java.util.Set;
 
 public interface Valuation {
@@ -20,4 +26,12 @@ public interface Valuation {
         default Valuation restrict(Set<? extends AnyDataVariable> allowedVariables) {
                 return new RestrictedValuation(this, Set.copyOf(allowedVariables));
         }
+
+        static ValuationBuilder builder() {
+                return new ValuationBuilder();
+        }
+
+        static Valuation empty() {
+                return new MapBasedValuation(Map.of());
+        }
 }
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/ValuationBuilder.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/ValuationBuilder.java
new file mode 100644
index 00000000..7337dbc3
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/valuation/ValuationBuilder.java
@@ -0,0 +1,40 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.valuation;
+
+import tools.refinery.store.query.term.AnyDataVariable;
+import tools.refinery.store.query.term.DataVariable;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+public class ValuationBuilder {
+        private final Map<AnyDataVariable, Object> values = new HashMap<>();
+
+        ValuationBuilder() {
+        }
+
+        public <T> ValuationBuilder put(DataVariable<T> variable, T value) {
+                return putChecked(variable, value);
+        }
+
+        public ValuationBuilder putChecked(AnyDataVariable variable, Object value) {
+                if (value != null && !variable.getType().isInstance(value)) {
+                        throw new IllegalArgumentException("Value %s is not an instance of %s"
+                                        .formatted(value, variable.getType().getName()));
+                }
+                if (values.containsKey(variable)) {
+                        throw new IllegalArgumentException("Already has value for variable %s".formatted(variable));
+                }
+                values.put(variable, value);
+                return this;
+        }
+
+        public Valuation build() {
+                return new MapBasedValuation(Collections.unmodifiableMap(values));
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/AbstractFunctionView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/AbstractFunctionView.java
new file mode 100644
index 00000000..c1f9d688
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/AbstractFunctionView.java
@@ -0,0 +1,112 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.view;
+
+import tools.refinery.store.model.Model;
+import tools.refinery.store.query.dnf.FunctionalDependency;
+import tools.refinery.store.query.term.Parameter;
+import tools.refinery.store.representation.Symbol;
+import tools.refinery.store.tuple.Tuple;
+import tools.refinery.store.tuple.Tuple1;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Objects;
+import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+public abstract class AbstractFunctionView<T> extends SymbolView<T> {
+        private final T defaultValue;
+        private final List<Parameter> parameters;
+
+        protected AbstractFunctionView(Symbol<T> symbol, String name, Parameter outParameter) {
+                super(symbol, name);
+                defaultValue = symbol.defaultValue();
+                parameters = createParameters(symbol.arity(), outParameter);
+        }
+
+        @Override
+        public Set<FunctionalDependency<Integer>> getFunctionalDependencies() {
+                var arity = getSymbol().arity();
+                var forEach = IntStream.range(0, arity).boxed().collect(Collectors.toUnmodifiableSet());
+                var unique = Set.of(arity);
+                return Set.of(new FunctionalDependency<>(forEach, unique));
+        }
+
+        @Override
+        public Set<ViewImplication> getImpliedRelationViews() {
+                var symbol = getSymbol();
+                var impliedIndices = IntStream.range(0, symbol.arity()).boxed().toList();
+                var keysView = new KeyOnlyView<>(symbol);
+                return Set.of(new ViewImplication(this, keysView, impliedIndices));
+        }
+
+        @Override
+        public final boolean filter(Tuple key, T value) {
+                return !Objects.equals(defaultValue, value);
+        }
+
+        protected Object forwardMapValue(Tuple key, T value) {
+                return value;
+        }
+
+        protected boolean valueEquals(Tuple key, T value, Object otherForwardMappedValue) {
+                return Objects.equals(otherForwardMappedValue, forwardMapValue(key, value));
+        }
+
+        @Override
+        public Object[] forwardMap(Tuple key, T value) {
+                int size = key.getSize();
+                Object[] result = new Object[size + 1];
+                for (int i = 0; i < size; i++) {
+                        result[i] = Tuple.of(key.get(i));
+                }
+                result[key.getSize()] = forwardMapValue(key, value);
+                return result;
+        }
+
+        @Override
+        public boolean get(Model model, Object[] tuple) {
+                int[] content = new int[tuple.length - 1];
+                for (int i = 0; i < tuple.length - 1; i++) {
+                        if (!(tuple[i] instanceof Tuple1 wrapper)) {
+                                return false;
+                        }
+                        content[i] = wrapper.value0();
+                }
+                Tuple key = Tuple.of(content);
+                var valueInTuple = tuple[tuple.length - 1];
+                T valueInMap = model.getInterpretation(getSymbol()).get(key);
+                return valueEquals(key, valueInMap, valueInTuple);
+        }
+
+        @Override
+        public List<Parameter> getParameters() {
+                return parameters;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                if (!super.equals(o)) return false;
+                AbstractFunctionView<?> that = (AbstractFunctionView<?>) o;
+                return Objects.equals(defaultValue, that.defaultValue) && Objects.equals(parameters, that.parameters);
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(super.hashCode(), defaultValue, parameters);
+        }
+
+        private static List<Parameter> createParameters(int symbolArity, Parameter outParameter) {
+                var parameters = new Parameter[symbolArity + 1];
+                Arrays.fill(parameters, Parameter.NODE_OUT);
+                parameters[symbolArity] = outParameter;
+                return List.of(parameters);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/AnyRelationView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/AnySymbolView.java
index 6ae410f2..90b27ebb 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/AnyRelationView.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/AnySymbolView.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.view;
 
 import tools.refinery.store.model.Model;
@@ -7,7 +12,7 @@ import tools.refinery.store.query.Constraint;
 
 import java.util.Set;
 
-public sealed interface AnyRelationView extends Constraint permits RelationView {
+public sealed interface AnySymbolView extends Constraint permits SymbolView {
         AnySymbol getSymbol();
 
         String getViewName();
@@ -16,7 +21,7 @@ public sealed interface AnyRelationView extends Constraint permits RelationView
                 return Set.of();
         }
 
-        default Set<RelationViewImplication> getImpliedRelationViews() {
+        default Set<ViewImplication> getImpliedRelationViews() {
                 return Set.of();
         }
 
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/FilteredRelationView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/FilteredView.java
index 64c601bb..922c7355 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/FilteredRelationView.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/FilteredView.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.view;
 
 import tools.refinery.store.tuple.Tuple;
@@ -7,24 +12,24 @@ import java.util.Objects;
 import java.util.function.BiPredicate;
 import java.util.function.Predicate;
 
-public class FilteredRelationView<T> extends TuplePreservingRelationView<T> {
+public class FilteredView<T> extends TuplePreservingView<T> {
         private final BiPredicate<Tuple, T> predicate;
 
-        public FilteredRelationView(Symbol<T> symbol, String name, BiPredicate<Tuple, T> predicate) {
+        public FilteredView(Symbol<T> symbol, String name, BiPredicate<Tuple, T> predicate) {
                 super(symbol, name);
                 this.predicate = predicate;
         }
 
-        public FilteredRelationView(Symbol<T> symbol, BiPredicate<Tuple, T> predicate) {
+        public FilteredView(Symbol<T> symbol, BiPredicate<Tuple, T> predicate) {
                 super(symbol);
                 this.predicate = predicate;
         }
 
-        public FilteredRelationView(Symbol<T> symbol, String name, Predicate<T> predicate) {
+        public FilteredView(Symbol<T> symbol, String name, Predicate<T> predicate) {
                 this(symbol, name, (k, v) -> predicate.test(v));
         }
 
-        public FilteredRelationView(Symbol<T> symbol, Predicate<T> predicate) {
+        public FilteredView(Symbol<T> symbol, Predicate<T> predicate) {
                 this(symbol, (k, v) -> predicate.test(v));
         }
 
@@ -38,7 +43,7 @@ public class FilteredRelationView<T> extends TuplePreservingRelationView<T> {
                 if (this == o) return true;
                 if (o == null || getClass() != o.getClass()) return false;
                 if (!super.equals(o)) return false;
-                FilteredRelationView<?> that = (FilteredRelationView<?>) o;
+                FilteredView<?> that = (FilteredView<?>) o;
                 return Objects.equals(predicate, that.predicate);
         }
 
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/ForbiddenRelationView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/ForbiddenView.java
index 050b9496..26b717ee 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/ForbiddenRelationView.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/ForbiddenView.java
@@ -1,11 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.view;
 
 import tools.refinery.store.representation.Symbol;
 import tools.refinery.store.representation.TruthValue;
 import tools.refinery.store.tuple.Tuple;
 
-public class ForbiddenRelationView extends TuplePreservingRelationView<TruthValue> {
-        public ForbiddenRelationView(Symbol<TruthValue> symbol) {
+public class ForbiddenView extends TuplePreservingView<TruthValue> {
+        public ForbiddenView(Symbol<TruthValue> symbol) {
                 super(symbol, "forbidden");
         }
 
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/FunctionView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/FunctionView.java
new file mode 100644
index 00000000..74a5be07
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/FunctionView.java
@@ -0,0 +1,36 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.view;
+
+import tools.refinery.store.query.term.*;
+import tools.refinery.store.representation.Symbol;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public final class FunctionView<T> extends AbstractFunctionView<T> {
+        public FunctionView(Symbol<T> symbol, String name) {
+                super(symbol, name, new Parameter(symbol.valueType(), ParameterDirection.OUT));
+        }
+
+        public FunctionView(Symbol<T> symbol) {
+                this(symbol, "function");
+        }
+
+        public <R> AssignedValue<R> aggregate(Aggregator<R, T> aggregator, List<NodeVariable> arguments) {
+                return targetVariable -> {
+                        var placeholderVariable = Variable.of(getSymbol().valueType());
+                        var argumentsWithPlaceholder = new ArrayList<Variable>(arguments.size() + 1);
+                        argumentsWithPlaceholder.addAll(arguments);
+                        argumentsWithPlaceholder.add(placeholderVariable);
+                        return aggregateBy(placeholderVariable, aggregator, argumentsWithPlaceholder).toLiteral(targetVariable);
+                };
+        }
+
+        public <R> AssignedValue<R> aggregate(Aggregator<R, T> aggregator, NodeVariable... arguments) {
+                return aggregate(aggregator, List.of(arguments));
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/FunctionalRelationView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/FunctionalRelationView.java
deleted file mode 100644
index 7ec9e7ac..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/FunctionalRelationView.java
+++ /dev/null
@@ -1,105 +0,0 @@
-package tools.refinery.store.query.view;
-
-import tools.refinery.store.model.Model;
-import tools.refinery.store.query.dnf.FunctionalDependency;
-import tools.refinery.store.query.term.DataSort;
-import tools.refinery.store.query.term.NodeSort;
-import tools.refinery.store.query.term.Sort;
-import tools.refinery.store.representation.Symbol;
-import tools.refinery.store.tuple.Tuple;
-import tools.refinery.store.tuple.Tuple1;
-
-import java.util.List;
-import java.util.Objects;
-import java.util.Set;
-import java.util.stream.Collectors;
-import java.util.stream.IntStream;
-
-public final class FunctionalRelationView<T> extends RelationView<T> {
-        private final T defaultValue;
-
-        public FunctionalRelationView(Symbol<T> symbol, String name) {
-                super(symbol, name);
-                defaultValue = symbol.defaultValue();
-        }
-
-        public FunctionalRelationView(Symbol<T> symbol) {
-                super(symbol);
-                defaultValue = symbol.defaultValue();
-        }
-
-        @Override
-        public Set<FunctionalDependency<Integer>> getFunctionalDependencies() {
-                var arity = getSymbol().arity();
-                var forEach = IntStream.range(0, arity).boxed().collect(Collectors.toUnmodifiableSet());
-                var unique = Set.of(arity);
-                return Set.of(new FunctionalDependency<>(forEach, unique));
-        }
-
-        @Override
-        public Set<RelationViewImplication> getImpliedRelationViews() {
-                var symbol = getSymbol();
-                var impliedIndices = IntStream.range(0, symbol.arity()).boxed().toList();
-                var keyOnlyRelationView = new KeyOnlyRelationView<>(symbol);
-                return Set.of(new RelationViewImplication(this, keyOnlyRelationView, impliedIndices));
-        }
-
-        @Override
-        public boolean filter(Tuple key, T value) {
-                return !Objects.equals(defaultValue, value);
-        }
-
-        @Override
-        public Object[] forwardMap(Tuple key, T value) {
-                int size = key.getSize();
-                Object[] result = new Object[size + 1];
-                for (int i = 0; i < size; i++) {
-                        result[i] = Tuple.of(key.get(i));
-                }
-                result[key.getSize()] = value;
-                return result;
-        }
-
-        @Override
-        public boolean get(Model model, Object[] tuple) {
-                int[] content = new int[tuple.length - 1];
-                for (int i = 0; i < tuple.length - 1; i++) {
-                        content[i] = ((Tuple1) tuple[i]).value0();
-                }
-                Tuple key = Tuple.of(content);
-                @SuppressWarnings("unchecked")
-                T valueInTuple = (T) tuple[tuple.length - 1];
-                T valueInMap = model.getInterpretation(getSymbol()).get(key);
-                return valueInTuple.equals(valueInMap);
-        }
-
-        @Override
-        public int arity() {
-                return getSymbol().arity() + 1;
-        }
-
-        @Override
-        public List<Sort> getSorts() {
-                var sorts = new Sort[arity()];
-                int valueIndex = sorts.length - 1;
-                for (int i = 0; i < valueIndex; i++) {
-                        sorts[i] = NodeSort.INSTANCE;
-                }
-                sorts[valueIndex] = new DataSort<>(getSymbol().valueType());
-                return List.of(sorts);
-        }
-
-        @Override
-        public boolean equals(Object o) {
-                if (this == o) return true;
-                if (o == null || getClass() != o.getClass()) return false;
-                if (!super.equals(o)) return false;
-                FunctionalRelationView<?> that = (FunctionalRelationView<?>) o;
-                return Objects.equals(defaultValue, that.defaultValue);
-        }
-
-        @Override
-        public int hashCode() {
-                return Objects.hash(super.hashCode(), defaultValue);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/KeyOnlyRelationView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/KeyOnlyView.java
index e1b2e45b..7e86f6e4 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/KeyOnlyRelationView.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/KeyOnlyView.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.view;
 
 import tools.refinery.store.representation.Symbol;
@@ -5,12 +10,12 @@ import tools.refinery.store.tuple.Tuple;
 
 import java.util.Objects;
 
-public final class KeyOnlyRelationView<T> extends TuplePreservingRelationView<T> {
+public final class KeyOnlyView<T> extends TuplePreservingView<T> {
         public static final String VIEW_NAME = "key";
 
         private final T defaultValue;
 
-        public KeyOnlyRelationView(Symbol<T> symbol) {
+        public KeyOnlyView(Symbol<T> symbol) {
                 super(symbol, VIEW_NAME);
                 defaultValue = symbol.defaultValue();
         }
@@ -25,7 +30,7 @@ public final class KeyOnlyRelationView<T> extends TuplePreservingRelationView<T>
                 if (this == o) return true;
                 if (o == null || getClass() != o.getClass()) return false;
                 if (!super.equals(o)) return false;
-                KeyOnlyRelationView<?> that = (KeyOnlyRelationView<?>) o;
+                KeyOnlyView<?> that = (KeyOnlyView<?>) o;
                 return Objects.equals(defaultValue, that.defaultValue);
         }
 
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/MayRelationView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/MayView.java
index a2a84b3c..e75a8171 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/MayRelationView.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/MayView.java
@@ -1,11 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.view;
 
 import tools.refinery.store.representation.Symbol;
 import tools.refinery.store.representation.TruthValue;
 import tools.refinery.store.tuple.Tuple;
 
-public class MayRelationView extends TuplePreservingRelationView<TruthValue> {
-        public MayRelationView(Symbol<TruthValue> symbol) {
+public class MayView extends TuplePreservingView<TruthValue> {
+        public MayView(Symbol<TruthValue> symbol) {
                 super(symbol, "may");
         }
 
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/MustRelationView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/MustView.java
index 72ac0ca3..a48f8045 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/MustRelationView.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/MustView.java
@@ -1,11 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.view;
 
 import tools.refinery.store.representation.Symbol;
 import tools.refinery.store.representation.TruthValue;
 import tools.refinery.store.tuple.Tuple;
 
-public class MustRelationView extends TuplePreservingRelationView<TruthValue> {
-        public MustRelationView(Symbol<TruthValue> symbol) {
+public class MustView extends TuplePreservingView<TruthValue> {
+        public MustView(Symbol<TruthValue> symbol) {
                 super(symbol, "must");
         }
 
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/NodeFunctionView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/NodeFunctionView.java
new file mode 100644
index 00000000..fcf11506
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/NodeFunctionView.java
@@ -0,0 +1,20 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.view;
+
+import tools.refinery.store.query.term.Parameter;
+import tools.refinery.store.representation.Symbol;
+import tools.refinery.store.tuple.Tuple1;
+
+public final class NodeFunctionView extends AbstractFunctionView<Tuple1> {
+        public NodeFunctionView(Symbol<Tuple1> symbol, String name) {
+                super(symbol, name, Parameter.NODE_OUT);
+        }
+
+        public NodeFunctionView(Symbol<Tuple1> symbol) {
+                this(symbol, "function");
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/RelationViewImplication.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/RelationViewImplication.java
deleted file mode 100644
index 2ba1fcc4..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/RelationViewImplication.java
+++ /dev/null
@@ -1,19 +0,0 @@
-package tools.refinery.store.query.view;
-
-import java.util.List;
-
-public record RelationViewImplication(AnyRelationView implyingRelationView, AnyRelationView impliedRelationView,
-                                                                          List<Integer> impliedIndices) {
-        public RelationViewImplication {
-                if (impliedIndices.size() != impliedRelationView.arity()) {
-                        throw new IllegalArgumentException("Expected %d implied indices for %s, but %d are provided"
-                                        .formatted(impliedRelationView.arity(), impliedRelationView, impliedIndices.size()));
-                }
-                for (var index : impliedIndices) {
-                        if (impliedRelationView.invalidIndex(index)) {
-                                throw new IllegalArgumentException("%d is not a valid index for %s".formatted(index,
-                                                implyingRelationView));
-                        }
-                }
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/RelationView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/SymbolView.java
index d7164b3b..267a99d3 100644
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/RelationView.java
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/SymbolView.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.view;
 
 import tools.refinery.store.map.CursorAsIterator;
@@ -14,17 +19,17 @@ import java.util.UUID;
  * @param <T>
  * @author Oszkar Semerath
  */
-public abstract non-sealed class RelationView<T> implements AnyRelationView {
+public abstract non-sealed class SymbolView<T> implements AnySymbolView {
         private final Symbol<T> symbol;
 
         private final String viewName;
 
-        protected RelationView(Symbol<T> symbol, String viewName) {
+        protected SymbolView(Symbol<T> symbol, String viewName) {
                 this.symbol = symbol;
                 this.viewName = viewName;
         }
 
-        protected RelationView(Symbol<T> representation) {
+        protected SymbolView(Symbol<T> representation) {
                 this(representation, UUID.randomUUID().toString());
         }
 
@@ -66,7 +71,7 @@ public abstract non-sealed class RelationView<T> implements AnyRelationView {
         public boolean equals(Object o) {
                 if (this == o) return true;
                 if (o == null || getClass() != o.getClass()) return false;
-                RelationView<?> that = (RelationView<?>) o;
+                SymbolView<?> that = (SymbolView<?>) o;
                 return Objects.equals(symbol, that.symbol) && Objects.equals(viewName, that.viewName);
         }
 
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/TuplePreservingRelationView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/TuplePreservingRelationView.java
deleted file mode 100644
index 234b3a9a..00000000
--- a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/TuplePreservingRelationView.java
+++ /dev/null
@@ -1,57 +0,0 @@
-package tools.refinery.store.query.view;
-
-import tools.refinery.store.model.Model;
-import tools.refinery.store.query.term.NodeSort;
-import tools.refinery.store.query.term.Sort;
-import tools.refinery.store.tuple.Tuple;
-import tools.refinery.store.tuple.Tuple1;
-import tools.refinery.store.representation.Symbol;
-
-import java.util.Arrays;
-import java.util.List;
-
-public abstract class TuplePreservingRelationView<T> extends RelationView<T> {
-        protected TuplePreservingRelationView(Symbol<T> symbol, String name) {
-                super(symbol, name);
-        }
-
-        protected TuplePreservingRelationView(Symbol<T> symbol) {
-                super(symbol);
-        }
-
-        public Object[] forwardMap(Tuple key) {
-                Object[] result = new Object[key.getSize()];
-                for (int i = 0; i < key.getSize(); i++) {
-                        result[i] = Tuple.of(key.get(i));
-                }
-                return result;
-        }
-
-        @Override
-        public Object[] forwardMap(Tuple key, T value) {
-                return forwardMap(key);
-        }
-
-        @Override
-        public boolean get(Model model, Object[] tuple) {
-                int[] content = new int[tuple.length];
-                for (int i = 0; i < tuple.length; i++) {
-                        content[i] = ((Tuple1) tuple[i]).value0();
-                }
-                Tuple key = Tuple.of(content);
-                T value = model.getInterpretation(getSymbol()).get(key);
-                return filter(key, value);
-        }
-
-        @Override
-        public int arity() {
-                return this.getSymbol().arity();
-        }
-
-        @Override
-        public List<Sort> getSorts() {
-                var sorts = new Sort[arity()];
-                Arrays.fill(sorts, NodeSort.INSTANCE);
-                return List.of(sorts);
-        }
-}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/TuplePreservingView.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/TuplePreservingView.java
new file mode 100644
index 00000000..6bc5a708
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/TuplePreservingView.java
@@ -0,0 +1,82 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.view;
+
+import tools.refinery.store.model.Model;
+import tools.refinery.store.query.term.Parameter;
+import tools.refinery.store.representation.Symbol;
+import tools.refinery.store.tuple.Tuple;
+import tools.refinery.store.tuple.Tuple1;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Objects;
+
+public abstract class TuplePreservingView<T> extends SymbolView<T> {
+        private final List<Parameter> parameters;
+
+        protected TuplePreservingView(Symbol<T> symbol, String name) {
+                super(symbol, name);
+                this.parameters = createParameters(symbol.arity());
+        }
+
+        protected TuplePreservingView(Symbol<T> symbol) {
+                super(symbol);
+                this.parameters = createParameters(symbol.arity());
+        }
+
+        public Object[] forwardMap(Tuple key) {
+                Object[] result = new Object[key.getSize()];
+                for (int i = 0; i < key.getSize(); i++) {
+                        result[i] = Tuple.of(key.get(i));
+                }
+                return result;
+        }
+
+        @Override
+        public Object[] forwardMap(Tuple key, T value) {
+                return forwardMap(key);
+        }
+
+        @Override
+        public boolean get(Model model, Object[] tuple) {
+                int[] content = new int[tuple.length];
+                for (int i = 0; i < tuple.length; i++) {
+                        if (!(tuple[i] instanceof Tuple1 wrapper)) {
+                                return false;
+                        }
+                        content[i] = wrapper.value0();
+                }
+                Tuple key = Tuple.of(content);
+                T value = model.getInterpretation(getSymbol()).get(key);
+                return filter(key, value);
+        }
+
+        @Override
+        public List<Parameter> getParameters() {
+                return parameters;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                if (!super.equals(o)) return false;
+                TuplePreservingView<?> that = (TuplePreservingView<?>) o;
+                return Objects.equals(parameters, that.parameters);
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(super.hashCode(), parameters);
+        }
+
+        private static List<Parameter> createParameters(int arity) {
+                var parameters = new Parameter[arity];
+                Arrays.fill(parameters, Parameter.NODE_OUT);
+                return List.of(parameters);
+        }
+}
diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/view/ViewImplication.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/ViewImplication.java
new file mode 100644
index 00000000..fc2db9f2
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/view/ViewImplication.java
@@ -0,0 +1,23 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.view;
+
+import java.util.List;
+
+public record ViewImplication(AnySymbolView implyingView, AnySymbolView impliedView, List<Integer> impliedIndices) {
+        public ViewImplication {
+                if (impliedIndices.size() != impliedView.arity()) {
+                        throw new IllegalArgumentException("Expected %d implied indices for %s, but %d are provided"
+                                        .formatted(impliedView.arity(), impliedView, impliedIndices.size()));
+                }
+                for (var index : impliedIndices) {
+                        if (impliedView.invalidIndex(index)) {
+                                throw new IllegalArgumentException("%d is not a valid index for %s".formatted(index,
+                                                implyingView));
+                        }
+                }
+        }
+}
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/DnfBuilderTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/DnfBuilderLiteralEliminationTest.java
index ceb46d6f..e17496e3 100644
--- a/subprojects/store-query/src/test/java/tools/refinery/store/query/DnfBuilderTest.java
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/DnfBuilderLiteralEliminationTest.java
@@ -1,24 +1,39 @@
-package tools.refinery.store.query;
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf;
 
 import org.junit.jupiter.api.Test;
-import tools.refinery.store.query.dnf.Dnf;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
 import tools.refinery.store.query.literal.BooleanLiteral;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.ParameterDirection;
 import tools.refinery.store.query.term.Variable;
-import tools.refinery.store.query.view.KeyOnlyRelationView;
+import tools.refinery.store.query.term.bool.BoolTerms;
+import tools.refinery.store.query.view.KeyOnlyView;
+import tools.refinery.store.query.view.SymbolView;
 import tools.refinery.store.representation.Symbol;
 
+import java.util.List;
+
 import static org.hamcrest.MatcherAssert.assertThat;
+import static tools.refinery.store.query.literal.Literals.assume;
 import static tools.refinery.store.query.literal.Literals.not;
 import static tools.refinery.store.query.tests.QueryMatchers.structurallyEqualTo;
 
-class DnfBuilderTest {
+class DnfBuilderLiteralEliminationTest {
+        private final Symbol<Boolean> friend = Symbol.of("friend", 2);
+        private final SymbolView<Boolean> friendView = new KeyOnlyView<>(friend);
+        private final NodeVariable p = Variable.of("p");
+        private final NodeVariable q = Variable.of("q");
+        private final Dnf trueDnf = Dnf.builder().parameter(p, ParameterDirection.IN).clause().build();
+        private final Dnf falseDnf = Dnf.builder().parameter(p).build();
+
         @Test
         void eliminateTrueTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
-
                 var actual = Dnf.builder()
                                 .parameters(p, q)
                                 .clause(BooleanLiteral.TRUE, friendView.call(p, q))
@@ -29,12 +44,18 @@ class DnfBuilderTest {
         }
 
         @Test
-        void eliminateFalseTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
+        void eliminateTrueAssumptionTest() {
+                var actual = Dnf.builder()
+                                .parameters(p, q)
+                                .clause(assume(BoolTerms.constant(true)), friendView.call(p, q))
+                                .build();
+                var expected = Dnf.builder().parameters(p, q).clause(friendView.call(p, q)).build();
+
+                assertThat(actual, structurallyEqualTo(expected));
+        }
 
+        @Test
+        void eliminateFalseTest() {
                 var actual = Dnf.builder()
                                 .parameters(p, q)
                                 .clause(friendView.call(p, q))
@@ -45,30 +66,36 @@ class DnfBuilderTest {
                 assertThat(actual, structurallyEqualTo(expected));
         }
 
+        @ParameterizedTest
+        @CsvSource(value = {
+                        "false",
+                        "null"
+        }, nullValues = "null")
+        void eliminateFalseAssumptionTest(Boolean value) {
+                var actual = Dnf.builder()
+                                .parameters(p, q)
+                                .clause(friendView.call(p, q))
+                                .clause(friendView.call(q, p), assume(BoolTerms.constant(value)))
+                                .build();
+                var expected = Dnf.builder().parameters(p, q).clause(friendView.call(p, q)).build();
+
+                assertThat(actual, structurallyEqualTo(expected));
+        }
+
         @Test
         void alwaysTrueTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
-
                 var actual = Dnf.builder()
-                                .parameters(p, q)
+                                .parameters(List.of(p, q), ParameterDirection.IN)
                                 .clause(friendView.call(p, q))
                                 .clause(BooleanLiteral.TRUE)
                                 .build();
-                var expected = Dnf.builder().parameters(p, q).clause().build();
+                var expected = Dnf.builder().parameters(List.of(p, q), ParameterDirection.IN).clause().build();
 
                 assertThat(actual, structurallyEqualTo(expected));
         }
 
         @Test
         void alwaysFalseTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
-
                 var actual = Dnf.builder()
                                 .parameters(p, q)
                                 .clause(friendView.call(p, q), BooleanLiteral.FALSE)
@@ -80,12 +107,6 @@ class DnfBuilderTest {
 
         @Test
         void eliminateTrueDnfTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
-                var trueDnf = Dnf.builder().parameter(p).clause().build();
-
                 var actual = Dnf.builder()
                                 .parameters(p, q)
                                 .clause(trueDnf.call(q), friendView.call(p, q))
@@ -97,12 +118,6 @@ class DnfBuilderTest {
 
         @Test
         void eliminateFalseDnfTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
-                var falseDnf = Dnf.builder().parameter(p).build();
-
                 var actual = Dnf.builder()
                                 .parameters(p, q)
                                 .clause(friendView.call(p, q))
@@ -115,30 +130,18 @@ class DnfBuilderTest {
 
         @Test
         void alwaysTrueDnfTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
-                var trueDnf = Dnf.builder().parameter(p).clause().build();
-
                 var actual = Dnf.builder()
-                                .parameters(p, q)
+                                .parameters(List.of(p, q), ParameterDirection.IN)
                                 .clause(friendView.call(p, q))
                                 .clause(trueDnf.call(q))
                                 .build();
-                var expected = Dnf.builder().parameters(p, q).clause().build();
+                var expected = Dnf.builder().parameters(List.of(p, q), ParameterDirection.IN).clause().build();
 
                 assertThat(actual, structurallyEqualTo(expected));
         }
 
         @Test
         void alwaysFalseDnfTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
-                var falseDnf = Dnf.builder().parameter(p).build();
-
                 var actual = Dnf.builder()
                                 .parameters(p, q)
                                 .clause(friendView.call(p, q), falseDnf.call(q))
@@ -150,12 +153,6 @@ class DnfBuilderTest {
 
         @Test
         void eliminateNotFalseDnfTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
-                var falseDnf = Dnf.builder().parameter(p).build();
-
                 var actual = Dnf.builder()
                                 .parameters(p, q)
                                 .clause(not(falseDnf.call(q)), friendView.call(p, q))
@@ -167,12 +164,6 @@ class DnfBuilderTest {
 
         @Test
         void eliminateNotTrueDnfTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
-                var trueDnf = Dnf.builder().parameter(p).clause().build();
-
                 var actual = Dnf.builder()
                                 .parameters(p, q)
                                 .clause(friendView.call(p, q))
@@ -185,30 +176,18 @@ class DnfBuilderTest {
 
         @Test
         void alwaysNotFalseDnfTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
-                var falseDnf = Dnf.builder().parameter(p).build();
-
                 var actual = Dnf.builder()
-                                .parameters(p, q)
+                                .parameters(List.of(p, q), ParameterDirection.IN)
                                 .clause(friendView.call(p, q))
                                 .clause(not(falseDnf.call(q)))
                                 .build();
-                var expected = Dnf.builder().parameters(p, q).clause().build();
+                var expected = Dnf.builder().parameters(List.of(p, q), ParameterDirection.IN).clause().build();
 
                 assertThat(actual, structurallyEqualTo(expected));
         }
 
         @Test
         void alwaysNotTrueDnfTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
-                var trueDnf = Dnf.builder().parameter(p).clause().build();
-
                 var actual = Dnf.builder()
                                 .parameters(p, q)
                                 .clause(friendView.call(p, q), not(trueDnf.call(q)))
@@ -217,4 +196,15 @@ class DnfBuilderTest {
 
                 assertThat(actual, structurallyEqualTo(expected));
         }
+
+        @Test
+        void removeDuplicateTest() {
+                var actual = Dnf.of(builder -> builder.clause((p, q) -> List.of(
+                                friendView.call(p, q),
+                                friendView.call(p, q)
+                )));
+                var expected = Dnf.of(builder -> builder.clause((p, q) -> List.of(friendView.call(p, q))));
+
+                assertThat(actual, structurallyEqualTo(expected));
+        }
 }
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/DnfBuilderVariableUnificationTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/DnfBuilderVariableUnificationTest.java
new file mode 100644
index 00000000..fc40c7b3
--- /dev/null
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/DnfBuilderVariableUnificationTest.java
@@ -0,0 +1,325 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf;
+
+import org.junit.jupiter.api.Test;
+import tools.refinery.store.query.term.ParameterDirection;
+import tools.refinery.store.query.term.Variable;
+import tools.refinery.store.query.view.KeyOnlyView;
+import tools.refinery.store.query.view.SymbolView;
+import tools.refinery.store.representation.Symbol;
+
+import java.util.List;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static tools.refinery.store.query.tests.QueryMatchers.structurallyEqualTo;
+
+class DnfBuilderVariableUnificationTest {
+        private final Symbol<Boolean> friend = Symbol.of("friend", 2);
+        private final Symbol<Boolean> children = Symbol.of("children", 2);
+        private final SymbolView<Boolean> friendView = new KeyOnlyView<>(friend);
+        private final SymbolView<Boolean> childrenView = new KeyOnlyView<>(children);
+
+        @Test
+        void equalToParameterTest() {
+                var actual = Dnf.of(builder -> {
+                        var p = builder.parameter("p");
+                        builder.clause(q -> List.of(
+                                        friendView.call(p, q),
+                                        p.isEquivalent(q)
+                        ));
+                });
+
+                var expectedP = Variable.of("p");
+                assertThat(actual, structurallyEqualTo(
+                                List.of(new SymbolicParameter(expectedP, ParameterDirection.OUT)),
+                                List.of(
+                                                List.of(friendView.call(expectedP, expectedP))
+                                )
+                ));
+        }
+
+        @Test
+        void equalToParameterReverseTest() {
+                var actual = Dnf.of(builder -> {
+                        var p = builder.parameter("p");
+                        builder.clause(q -> List.of(
+                                        friendView.call(p, q),
+                                        q.isEquivalent(p)
+                        ));
+                });
+
+                var expectedP = Variable.of("p");
+                assertThat(actual, structurallyEqualTo(
+                                List.of(new SymbolicParameter(expectedP, ParameterDirection.OUT)),
+                                List.of(
+                                                List.of(friendView.call(expectedP, expectedP))
+                                )
+                ));
+        }
+
+        @Test
+        void equalQuantifiedTest() {
+                var actual = Dnf.of(builder -> builder.clause((p, q) -> List.of(
+                                friendView.call(p, q),
+                                p.isEquivalent(q)
+                )));
+
+                var expectedP = Variable.of("p");
+                assertThat(actual, structurallyEqualTo(
+                                List.of(),
+                                List.of(
+                                                List.of(friendView.call(expectedP, expectedP))
+                                )
+                ));
+        }
+
+        @Test
+        void equalQuantifiedTransitiveTest() {
+                var actual = Dnf.of(builder -> builder.clause((p, q, r) -> List.of(
+                                friendView.call(p, q),
+                                p.isEquivalent(q),
+                                childrenView.call(p, r),
+                                q.isEquivalent(r)
+                )));
+
+                var expectedP = Variable.of("p");
+                assertThat(actual, structurallyEqualTo(
+                                List.of(),
+                                List.of(
+                                                List.of(friendView.call(expectedP, expectedP), childrenView.call(expectedP, expectedP))
+                                )
+                ));
+        }
+
+        @Test
+        void equalQuantifiedTransitiveRemoveDuplicateTest() {
+                var actual = Dnf.of(builder -> builder.clause((p, q, r) -> List.of(
+                                friendView.call(p, q),
+                                p.isEquivalent(q),
+                                friendView.call(p, r),
+                                q.isEquivalent(r)
+                )));
+
+                var expectedP = Variable.of("p");
+                assertThat(actual, structurallyEqualTo(
+                                List.of(),
+                                List.of(
+                                                List.of(friendView.call(expectedP, expectedP))
+                                )
+                ));
+        }
+
+        @Test
+        void parametersEqualTest() {
+                var actual = Dnf.of(builder -> {
+                        var p = builder.parameter("p");
+                        var q = builder.parameter("q");
+                        builder.clause(
+                                        friendView.call(p, q),
+                                        p.isEquivalent(q)
+                        );
+                });
+
+                var expectedP = Variable.of("p");
+                var expectedQ = Variable.of("q");
+                assertThat(actual, structurallyEqualTo(
+                                List.of(
+                                                new SymbolicParameter(expectedP, ParameterDirection.OUT),
+                                                new SymbolicParameter(expectedQ, ParameterDirection.OUT)
+                                ),
+                                List.of(
+                                                List.of(friendView.call(expectedP, expectedP), expectedQ.isEquivalent(expectedP))
+                                )
+                ));
+        }
+
+        @Test
+        void parametersEqualTransitiveTest() {
+                var actual = Dnf.of(builder -> {
+                        var p = builder.parameter("p");
+                        var q = builder.parameter("q");
+                        var r = builder.parameter("r");
+                        builder.clause(
+                                        friendView.call(p, q),
+                                        childrenView.call(p, r),
+                                        p.isEquivalent(q),
+                                        r.isEquivalent(q)
+                        );
+                });
+
+                var expectedP = Variable.of("p");
+                var expectedQ = Variable.of("q");
+                var expectedR = Variable.of("r");
+                assertThat(actual, structurallyEqualTo(
+                                List.of(
+                                                new SymbolicParameter(expectedP, ParameterDirection.OUT),
+                                                new SymbolicParameter(expectedQ, ParameterDirection.OUT),
+                                                new SymbolicParameter(expectedR, ParameterDirection.OUT)
+                                ),
+                                List.of(
+                                                List.of(
+                                                                friendView.call(expectedP, expectedP),
+                                                                expectedQ.isEquivalent(expectedP),
+                                                                expectedR.isEquivalent(expectedP),
+                                                                childrenView.call(expectedP, expectedP)
+                                                )
+                                )
+                ));
+        }
+
+        @Test
+        void parameterAndQuantifiedEqualsTest() {
+                var actual = Dnf.of(builder -> {
+                        var p = builder.parameter("p");
+                        var q = builder.parameter("q");
+                        builder.clause((r) -> List.of(
+                                        friendView.call(p, r),
+                                        p.isEquivalent(r),
+                                        childrenView.call(q, r),
+                                        q.isEquivalent(r)
+                        ));
+                });
+
+
+                var expectedP = Variable.of("p");
+                var expectedQ = Variable.of("q");
+                assertThat(actual, structurallyEqualTo(
+                                List.of(
+                                                new SymbolicParameter(expectedP, ParameterDirection.OUT),
+                                                new SymbolicParameter(expectedQ, ParameterDirection.OUT)
+                                ),
+                                List.of(
+                                                List.of(
+                                                                friendView.call(expectedP, expectedP),
+                                                                expectedQ.isEquivalent(expectedP),
+                                                                childrenView.call(expectedP, expectedP)
+                                                )
+                                )
+                ));
+        }
+
+        @Test
+        void parameterAndQuantifiedEqualsReverseFirstTest() {
+                var actual = Dnf.of(builder -> {
+                        var p = builder.parameter("p");
+                        var q = builder.parameter("q");
+                        builder.clause((r) -> List.of(
+                                        friendView.call(p, r),
+                                        r.isEquivalent(p),
+                                        childrenView.call(q, r),
+                                        q.isEquivalent(r)
+                        ));
+                });
+
+                var expectedP = Variable.of("p");
+                var expectedQ = Variable.of("q");
+                assertThat(actual, structurallyEqualTo(
+                                List.of(
+                                                new SymbolicParameter(expectedP, ParameterDirection.OUT),
+                                                new SymbolicParameter(expectedQ, ParameterDirection.OUT)
+                                ),
+                                List.of(
+                                                List.of(
+                                                                friendView.call(expectedP, expectedP),
+                                                                expectedQ.isEquivalent(expectedP),
+                                                                childrenView.call(expectedP, expectedP)
+                                                )
+                                )
+                ));
+        }
+
+        @Test
+        void parameterAndQuantifiedEqualsReverseSecondTest() {
+                var actual = Dnf.of(builder -> {
+                        var p = builder.parameter("p");
+                        var q = builder.parameter("q");
+                        builder.clause((r) -> List.of(
+                                        friendView.call(p, r),
+                                        p.isEquivalent(r),
+                                        childrenView.call(q, r),
+                                        r.isEquivalent(q)
+                        ));
+                });
+
+                var expectedP = Variable.of("p");
+                var expectedQ = Variable.of("q");
+                assertThat(actual, structurallyEqualTo(
+                                List.of(
+                                                new SymbolicParameter(expectedP, ParameterDirection.OUT),
+                                                new SymbolicParameter(expectedQ, ParameterDirection.OUT)
+                                ),
+                                List.of(
+                                                List.of(
+                                                                friendView.call(expectedP, expectedP),
+                                                                expectedQ.isEquivalent(expectedP),
+                                                                childrenView.call(expectedP, expectedP)
+                                                )
+                                )
+                ));
+        }
+
+        @Test
+        void parameterAndQuantifiedEqualsReverseBoth() {
+                var actual = Dnf.of(builder -> {
+                        var p = builder.parameter("p");
+                        var q = builder.parameter("q");
+                        builder.clause((r) -> List.of(
+                                        friendView.call(p, r),
+                                        p.isEquivalent(r),
+                                        childrenView.call(q, r),
+                                        r.isEquivalent(q)
+                        ));
+                });
+
+                var expectedP = Variable.of("p");
+                var expectedQ = Variable.of("q");
+                assertThat(actual, structurallyEqualTo(
+                                List.of(
+                                                new SymbolicParameter(expectedP, ParameterDirection.OUT),
+                                                new SymbolicParameter(expectedQ, ParameterDirection.OUT)
+                                ),
+                                List.of(
+                                                List.of(
+                                                                friendView.call(expectedP, expectedP),
+                                                                expectedQ.isEquivalent(expectedP),
+                                                                childrenView.call(expectedP, expectedP)
+                                                )
+                                )
+                ));
+        }
+
+        @Test
+        void parameterAndTwoQuantifiedEqualsTest() {
+                var actual = Dnf.of(builder -> {
+                        var p = builder.parameter("p");
+                        var q = builder.parameter("q");
+                        builder.clause((r, s) -> List.of(
+                                        r.isEquivalent(s),
+                                        friendView.call(p, r),
+                                        p.isEquivalent(r),
+                                        childrenView.call(q, s),
+                                        q.isEquivalent(s)
+                        ));
+                });
+
+                var expectedP = Variable.of("p");
+                var expectedQ = Variable.of("q");
+                assertThat(actual, structurallyEqualTo(
+                                List.of(
+                                                new SymbolicParameter(expectedP, ParameterDirection.OUT),
+                                                new SymbolicParameter(expectedQ, ParameterDirection.OUT)
+                                ),
+                                List.of(
+                                                List.of(
+                                                                friendView.call(expectedP, expectedP),
+                                                                expectedQ.isEquivalent(expectedP),
+                                                                childrenView.call(expectedP, expectedP)
+                                                )
+                                )
+                ));
+        }
+}
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/DnfToDefinitionStringTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/DnfToDefinitionStringTest.java
index 9b469bb0..d75d7f17 100644
--- a/subprojects/store-query/src/test/java/tools/refinery/store/query/DnfToDefinitionStringTest.java
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/DnfToDefinitionStringTest.java
@@ -1,9 +1,16 @@
-package tools.refinery.store.query;
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf;
 
 import org.junit.jupiter.api.Test;
-import tools.refinery.store.query.dnf.Dnf;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.ParameterDirection;
 import tools.refinery.store.query.term.Variable;
-import tools.refinery.store.query.view.KeyOnlyRelationView;
+import tools.refinery.store.query.view.AnySymbolView;
+import tools.refinery.store.query.view.KeyOnlyView;
 import tools.refinery.store.representation.Symbol;
 
 import static org.hamcrest.MatcherAssert.assertThat;
@@ -11,9 +18,15 @@ import static org.hamcrest.Matchers.is;
 import static tools.refinery.store.query.literal.Literals.not;
 
 class DnfToDefinitionStringTest {
+        private static final Symbol<Boolean> person = Symbol.of("person", 1);
+        private static final Symbol<Boolean> friend = Symbol.of("friend", 2);
+        private static final AnySymbolView personView = new KeyOnlyView<>(person);
+        private static final AnySymbolView friendView = new KeyOnlyView<>(friend);
+        private static final NodeVariable p = Variable.of("p");
+        private static final NodeVariable q = Variable.of("q");
+
         @Test
         void noClausesTest() {
-                var p = Variable.of("p");
                 var dnf = Dnf.builder("Example").parameter(p).build();
 
                 assertThat(dnf.toDefinitionString(), is("""
@@ -34,21 +47,16 @@ class DnfToDefinitionStringTest {
 
         @Test
         void emptyClauseTest() {
-                var p = Variable.of("p");
-                var dnf = Dnf.builder("Example").parameter(p).clause().build();
+                var dnf = Dnf.builder("Example").parameter(p, ParameterDirection.IN).clause().build();
 
                 assertThat(dnf.toDefinitionString(), is("""
-                                pred Example(p) <->
+                                pred Example(@In p) <->
                                     <empty>.
                                 """));
         }
 
         @Test
         void relationViewPositiveTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
                 var dnf = Dnf.builder("Example").parameter(p).clause(friendView.call(p, q)).build();
 
                 assertThat(dnf.toDefinitionString(), is("""
@@ -59,24 +67,19 @@ class DnfToDefinitionStringTest {
 
         @Test
         void relationViewNegativeTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
-                var dnf = Dnf.builder("Example").parameter(p).clause(not(friendView.call(p, q))).build();
+                var dnf = Dnf.builder("Example")
+                                .parameter(p, ParameterDirection.IN)
+                                .clause(not(friendView.call(p, q)))
+                                .build();
 
                 assertThat(dnf.toDefinitionString(), is("""
-                                pred Example(p) <->
+                                pred Example(@In p) <->
                                     !(@RelationView("key") friend(p, q)).
                                 """));
         }
 
         @Test
         void relationViewTransitiveTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
                 var dnf = Dnf.builder("Example").parameter(p).clause(friendView.callTransitive(p, q)).build();
 
                 assertThat(dnf.toDefinitionString(), is("""
@@ -87,10 +90,6 @@ class DnfToDefinitionStringTest {
 
         @Test
         void multipleParametersTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
                 var dnf = Dnf.builder("Example").parameters(p, q).clause(friendView.call(p, q)).build();
 
                 assertThat(dnf.toDefinitionString(), is("""
@@ -101,12 +100,6 @@ class DnfToDefinitionStringTest {
 
         @Test
         void multipleLiteralsTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var person = new Symbol<>("person", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
                 var dnf = Dnf.builder("Example")
                                 .parameter(p)
                                 .clause(
@@ -126,10 +119,6 @@ class DnfToDefinitionStringTest {
 
         @Test
         void multipleClausesTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
                 var dnf = Dnf.builder("Example")
                                 .parameter(p)
                                 .clause(friendView.call(p, q))
@@ -146,14 +135,8 @@ class DnfToDefinitionStringTest {
 
         @Test
         void dnfTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
                 var r = Variable.of("r");
                 var s = Variable.of("s");
-                var person = new Symbol<>("person", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-                var friendView = new KeyOnlyRelationView<>(friend);
                 var called  = Dnf.builder("Called").parameters(r, s).clause(friendView.call(r, s)).build();
                 var dnf = Dnf.builder("Example")
                                 .parameter(p)
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/TopologicalSortTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/TopologicalSortTest.java
new file mode 100644
index 00000000..e22dbb21
--- /dev/null
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/TopologicalSortTest.java
@@ -0,0 +1,112 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf;
+
+import org.junit.jupiter.api.Test;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.ParameterDirection;
+import tools.refinery.store.query.term.Variable;
+import tools.refinery.store.query.view.AnySymbolView;
+import tools.refinery.store.query.view.KeyOnlyView;
+import tools.refinery.store.representation.Symbol;
+
+import java.util.List;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static tools.refinery.store.query.literal.Literals.not;
+import static tools.refinery.store.query.tests.QueryMatchers.structurallyEqualTo;
+
+class TopologicalSortTest {
+        private static final Symbol<Boolean> friend = Symbol.of("friend", 2);
+        private static final AnySymbolView friendView = new KeyOnlyView<>(friend);
+        private static final Dnf example = Dnf.of("example", builder -> {
+                var a = builder.parameter("a", ParameterDirection.IN);
+                var b = builder.parameter("b", ParameterDirection.IN);
+                var c = builder.parameter("c", ParameterDirection.OUT);
+                var d = builder.parameter("d", ParameterDirection.OUT);
+                builder.clause(
+                                friendView.call(a, b),
+                                friendView.call(b, c),
+                                friendView.call(c, d)
+                );
+        });
+        private static final NodeVariable p = Variable.of("p");
+        private static final NodeVariable q = Variable.of("q");
+        private static final NodeVariable r = Variable.of("r");
+        private static final NodeVariable s = Variable.of("s");
+        private static final NodeVariable t = Variable.of("t");
+
+        @Test
+        void topologicalSortTest() {
+                var actual = Dnf.builder("Actual")
+                                .parameter(p, ParameterDirection.IN)
+                                .parameter(q, ParameterDirection.OUT)
+                                .clause(
+                                                not(friendView.call(p, q)),
+                                                example.call(p, q, r, s),
+                                                example.call(r, t, q, s),
+                                                friendView.call(r, t)
+                                )
+                                .build();
+
+                assertThat(actual, structurallyEqualTo(
+                                List.of(
+                                                new SymbolicParameter(p, ParameterDirection.IN),
+                                                new SymbolicParameter(q, ParameterDirection.OUT)
+                                ),
+                                List.of(
+                                                List.of(
+                                                                friendView.call(r, t),
+                                                                example.call(r, t, q, s),
+                                                                not(friendView.call(p, q)),
+                                                                example.call(p, q, r, s)
+                                                )
+                                )
+                ));
+        }
+
+        @Test
+        void missingInputTest() {
+                var builder = Dnf.builder("Actual")
+                                .parameter(p, ParameterDirection.OUT)
+                                .parameter(q, ParameterDirection.OUT)
+                                .clause(
+                                                not(friendView.call(p, q)),
+                                                example.call(p, q, r, s),
+                                                example.call(r, t, q, s),
+                                                friendView.call(r, t)
+                                );
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        @Test
+        void missingVariableTest() {
+                var builder = Dnf.builder("Actual")
+                                .parameter(p, ParameterDirection.IN)
+                                .parameter(q, ParameterDirection.OUT)
+                                .clause(
+                                                not(friendView.call(p, q)),
+                                                example.call(p, q, r, s),
+                                                example.call(r, t, q, s)
+                                );
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        @Test
+        void circularDependencyTest() {
+                var builder = Dnf.builder("Actual")
+                                .parameter(p, ParameterDirection.IN)
+                                .parameter(q, ParameterDirection.OUT)
+                                .clause(
+                                                not(friendView.call(p, q)),
+                                                example.call(p, q, r, s),
+                                                example.call(r, t, q, s),
+                                                example.call(p, q, r, t)
+                                );
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+}
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/VariableDirectionTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/VariableDirectionTest.java
new file mode 100644
index 00000000..c52d26b2
--- /dev/null
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/dnf/VariableDirectionTest.java
@@ -0,0 +1,428 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.dnf;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+import tools.refinery.store.query.literal.BooleanLiteral;
+import tools.refinery.store.query.literal.Literal;
+import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.ParameterDirection;
+import tools.refinery.store.query.term.Variable;
+import tools.refinery.store.query.view.AnySymbolView;
+import tools.refinery.store.query.view.FunctionView;
+import tools.refinery.store.query.view.KeyOnlyView;
+import tools.refinery.store.representation.Symbol;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Stream;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.hasItem;
+import static org.hamcrest.Matchers.not;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static tools.refinery.store.query.literal.Literals.assume;
+import static tools.refinery.store.query.literal.Literals.not;
+import static tools.refinery.store.query.term.int_.IntTerms.*;
+
+class VariableDirectionTest {
+        private static final Symbol<Boolean> person = Symbol.of("Person", 1);
+        private static final Symbol<Boolean> friend = Symbol.of("friend", 2);
+        private static final Symbol<Integer> age = Symbol.of("age", 1, Integer.class);
+        private static final AnySymbolView personView = new KeyOnlyView<>(person);
+        private static final AnySymbolView friendView = new KeyOnlyView<>(friend);
+        private static final FunctionView<Integer> ageView = new FunctionView<>(age);
+        private static final NodeVariable p = Variable.of("p");
+        private static final NodeVariable q = Variable.of("q");
+        private static final DataVariable<Integer> x = Variable.of("x", Integer.class);
+        private static final DataVariable<Integer> y = Variable.of("y", Integer.class);
+        private static final DataVariable<Integer> z = Variable.of("z", Integer.class);
+
+        @ParameterizedTest
+        @MethodSource("clausesWithVariableInput")
+        void unboundOutVariableTest(List<? extends Literal> clause) {
+                var builder = Dnf.builder().parameter(p, ParameterDirection.OUT).clause(clause);
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        @ParameterizedTest
+        @MethodSource("clausesWithVariableInput")
+        void unboundInVariableTest(List<? extends Literal> clause) {
+                var builder = Dnf.builder().parameter(p, ParameterDirection.IN).clause(clause);
+                var dnf = assertDoesNotThrow(builder::build);
+                var clauses = dnf.getClauses();
+                if (clauses.size() > 0) {
+                        assertThat(clauses.get(0).positiveVariables(), hasItem(p));
+                }
+        }
+
+        @ParameterizedTest
+        @MethodSource("clausesWithVariableInput")
+        void boundPrivateVariableTest(List<? extends Literal> clause) {
+                var clauseWithBinding = new ArrayList<Literal>(clause);
+                clauseWithBinding.add(personView.call(p));
+                var builder = Dnf.builder().clause(clauseWithBinding);
+                var dnf = assertDoesNotThrow(builder::build);
+                var clauses = dnf.getClauses();
+                if (clauses.size() > 0) {
+                        assertThat(clauses.get(0).positiveVariables(), hasItem(p));
+                }
+        }
+
+        static Stream<Arguments> clausesWithVariableInput() {
+                return Stream.concat(
+                                clausesNotBindingVariable(),
+                                literalToClauseArgumentStream(literalsWithRequiredVariableInput())
+                );
+        }
+
+        @ParameterizedTest
+        @MethodSource("clausesNotBindingVariable")
+        void unboundPrivateVariableTest(List<? extends Literal> clause) {
+                var builder = Dnf.builder().clause(clause);
+                var dnf = assertDoesNotThrow(builder::build);
+                var clauses = dnf.getClauses();
+                if (clauses.size() > 0) {
+                        assertThat(clauses.get(0).positiveVariables(), not(hasItem(p)));
+                }
+        }
+
+        @ParameterizedTest
+        @MethodSource("clausesNotBindingVariable")
+        void unboundByEquivalencePrivateVariableTest(List<? extends Literal> clause) {
+                var r = Variable.of("r");
+                var clauseWithEquivalence = new ArrayList<Literal>(clause);
+                clauseWithEquivalence.add(r.isEquivalent(p));
+                var builder = Dnf.builder().clause(clauseWithEquivalence);
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        static Stream<Arguments> clausesNotBindingVariable() {
+                return Stream.concat(
+                                Stream.of(
+                                        Arguments.of(List.of()),
+                                        Arguments.of(List.of(BooleanLiteral.TRUE)),
+                                        Arguments.of(List.of(BooleanLiteral.FALSE))
+                                ),
+                                literalToClauseArgumentStream(literalsWithPrivateVariable())
+                );
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithPrivateVariable")
+        void unboundTwicePrivateVariableTest(Literal literal) {
+                var builder = Dnf.builder().clause(not(personView.call(p)), literal);
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithPrivateVariable")
+        void unboundTwiceByEquivalencePrivateVariableTest(Literal literal) {
+                var r = Variable.of("r");
+                var builder = Dnf.builder().clause(not(personView.call(r)), r.isEquivalent(p), literal);
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        static Stream<Arguments> literalsWithPrivateVariable() {
+                var dnfWithOutput = Dnf.builder("WithOutput")
+                                .parameter(p, ParameterDirection.OUT)
+                                .parameter(q, ParameterDirection.OUT)
+                                .clause(friendView.call(p, q))
+                                .build();
+                var dnfWithOutputToAggregate = Dnf.builder("WithOutputToAggregate")
+                                .parameter(p, ParameterDirection.OUT)
+                                .parameter(q, ParameterDirection.OUT)
+                                .parameter(x, ParameterDirection.OUT)
+                                .clause(
+                                                friendView.call(p, q),
+                                                ageView.call(q, x)
+                                )
+                                .build();
+
+                return Stream.of(
+                                Arguments.of(not(friendView.call(p, q))),
+                                Arguments.of(y.assign(friendView.count(p, q))),
+                                Arguments.of(y.assign(ageView.aggregate(INT_SUM, p))),
+                                Arguments.of(not(dnfWithOutput.call(p, q))),
+                                Arguments.of(y.assign(dnfWithOutput.count(p, q))),
+                                Arguments.of(y.assign(dnfWithOutputToAggregate.aggregateBy(z, INT_SUM, p, q, z)))
+                );
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithRequiredVariableInput")
+        void unboundPrivateVariableTest(Literal literal) {
+                var builder = Dnf.builder().clause(literal);
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithRequiredVariableInput")
+        void boundPrivateVariableInputTest(Literal literal) {
+                var builder = Dnf.builder().clause(personView.call(p), literal);
+                var dnf = assertDoesNotThrow(builder::build);
+                assertThat(dnf.getClauses().get(0).positiveVariables(), hasItem(p));
+        }
+
+        static Stream<Arguments> literalsWithRequiredVariableInput() {
+                var dnfWithInput = Dnf.builder("WithInput")
+                                .parameter(p, ParameterDirection.IN)
+                                .parameter(q, ParameterDirection.OUT)
+                                .clause(friendView.call(p, q)).build();
+                var dnfWithInputToAggregate = Dnf.builder("WithInputToAggregate")
+                                .parameter(p, ParameterDirection.IN)
+                                .parameter(q, ParameterDirection.OUT)
+                                .parameter(x, ParameterDirection.OUT)
+                                .clause(
+                                                friendView.call(p, q),
+                                                ageView.call(q, x)
+                                ).build();
+
+                return Stream.of(
+                                Arguments.of(dnfWithInput.call(p, q)),
+                                Arguments.of(dnfWithInput.call(p, p)),
+                                Arguments.of(not(dnfWithInput.call(p, q))),
+                                Arguments.of(not(dnfWithInput.call(p, p))),
+                                Arguments.of(y.assign(dnfWithInput.count(p, q))),
+                                Arguments.of(y.assign(dnfWithInput.count(p, p))),
+                                Arguments.of(y.assign(dnfWithInputToAggregate.aggregateBy(z, INT_SUM, p, q, z))),
+                                Arguments.of(y.assign(dnfWithInputToAggregate.aggregateBy(z, INT_SUM, p, p, z)))
+                );
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithVariableOutput")
+        void boundParameterTest(Literal literal) {
+                var builder = Dnf.builder().parameter(p, ParameterDirection.OUT).clause(literal);
+                var dnf = assertDoesNotThrow(builder::build);
+                assertThat(dnf.getClauses().get(0).positiveVariables(), hasItem(p));
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithVariableOutput")
+        void boundTwiceParameterTest(Literal literal) {
+                var builder = Dnf.builder().parameter(p, ParameterDirection.IN).clause(literal);
+                var dnf = assertDoesNotThrow(builder::build);
+                assertThat(dnf.getClauses().get(0).positiveVariables(), hasItem(p));
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithVariableOutput")
+        void boundPrivateVariableOutputTest(Literal literal) {
+                var dnfWithInput = Dnf.builder("WithInput")
+                                .parameter(p, ParameterDirection.IN)
+                                .clause(personView.call(p))
+                                .build();
+                var builder = Dnf.builder().clause(dnfWithInput.call(p), literal);
+                var dnf = assertDoesNotThrow(builder::build);
+                assertThat(dnf.getClauses().get(0).positiveVariables(), hasItem(p));
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithVariableOutput")
+        void boundTwicePrivateVariableOutputTest(Literal literal) {
+                var builder = Dnf.builder().clause(personView.call(p), literal);
+                var dnf = assertDoesNotThrow(builder::build);
+                assertThat(dnf.getClauses().get(0).positiveVariables(), hasItem(p));
+        }
+
+        static Stream<Arguments> literalsWithVariableOutput() {
+                var dnfWithOutput = Dnf.builder("WithOutput")
+                                .parameter(p, ParameterDirection.OUT)
+                                .parameter(q, ParameterDirection.OUT)
+                                .clause(friendView.call(p, q))
+                                .build();
+
+                return Stream.of(
+                                Arguments.of(friendView.call(p, q)),
+                                Arguments.of(dnfWithOutput.call(p, q))
+                );
+        }
+
+        @ParameterizedTest
+        @MethodSource("clausesWithDataVariableInput")
+        void unboundOutDataVariableTest(List<? extends Literal> clause) {
+                var builder = Dnf.builder().parameter(x, ParameterDirection.OUT).clause(clause);
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        @ParameterizedTest
+        @MethodSource("clausesWithDataVariableInput")
+        void unboundInDataVariableTest(List<? extends Literal> clause) {
+                var builder = Dnf.builder().parameter(x, ParameterDirection.IN).clause(clause);
+                var dnf = assertDoesNotThrow(builder::build);
+                var clauses = dnf.getClauses();
+                if (clauses.size() > 0) {
+                        assertThat(clauses.get(0).positiveVariables(), hasItem(x));
+                }
+        }
+
+        @ParameterizedTest
+        @MethodSource("clausesWithDataVariableInput")
+        void boundPrivateDataVariableTest(List<? extends Literal> clause) {
+                var clauseWithBinding = new ArrayList<Literal>(clause);
+                clauseWithBinding.add(x.assign(constant(27)));
+                var builder = Dnf.builder().clause(clauseWithBinding);
+                var dnf = assertDoesNotThrow(builder::build);
+                var clauses = dnf.getClauses();
+                if (clauses.size() > 0) {
+                        assertThat(clauses.get(0).positiveVariables(), hasItem(x));
+                }
+        }
+
+        static Stream<Arguments> clausesWithDataVariableInput() {
+                return Stream.concat(
+                                clausesNotBindingDataVariable(),
+                                literalToClauseArgumentStream(literalsWithRequiredDataVariableInput())
+                );
+        }
+
+        @ParameterizedTest
+        @MethodSource("clausesNotBindingDataVariable")
+        void unboundPrivateDataVariableTest(List<? extends Literal> clause) {
+                var builder = Dnf.builder().clause(clause);
+                var dnf = assertDoesNotThrow(builder::build);
+                var clauses = dnf.getClauses();
+                if (clauses.size() > 0) {
+                        assertThat(clauses.get(0).positiveVariables(), not(hasItem(x)));
+                }
+        }
+
+        static Stream<Arguments> clausesNotBindingDataVariable() {
+                return Stream.concat(
+                                Stream.of(
+                                                Arguments.of(List.of()),
+                                                Arguments.of(List.of(BooleanLiteral.TRUE)),
+                                                Arguments.of(List.of(BooleanLiteral.FALSE))
+                                ),
+                                literalToClauseArgumentStream(literalsWithPrivateDataVariable())
+                );
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithPrivateDataVariable")
+        void unboundTwicePrivateDataVariableTest(Literal literal) {
+                var builder = Dnf.builder().clause(not(ageView.call(p, x)), literal);
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        static Stream<Arguments> literalsWithPrivateDataVariable() {
+                var dnfWithOutput = Dnf.builder("WithDataOutput")
+                                .parameter(y, ParameterDirection.OUT)
+                                .parameter(q, ParameterDirection.OUT)
+                                .clause(ageView.call(q, y))
+                                .build();
+
+                return Stream.of(
+                                Arguments.of(not(ageView.call(q, x))),
+                                Arguments.of(y.assign(ageView.count(q, x))),
+                                Arguments.of(not(dnfWithOutput.call(x, q)))
+                );
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithRequiredDataVariableInput")
+        void unboundPrivateDataVariableTest(Literal literal) {
+                var builder = Dnf.builder().clause(literal);
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        static Stream<Arguments> literalsWithRequiredDataVariableInput() {
+                var dnfWithInput = Dnf.builder("WithDataInput")
+                                .parameter(y, ParameterDirection.IN)
+                                .parameter(q, ParameterDirection.OUT)
+                                .clause(ageView.call(q, x))
+                                .build();
+                // We are passing {@code y} to the parameter named {@code right} of {@code greaterEq}.
+                @SuppressWarnings("SuspiciousNameCombination")
+                var dnfWithInputToAggregate = Dnf.builder("WithDataInputToAggregate")
+                                .parameter(y, ParameterDirection.IN)
+                                .parameter(q, ParameterDirection.OUT)
+                                .parameter(x, ParameterDirection.OUT)
+                                .clause(
+                                                friendView.call(p, q),
+                                                ageView.call(q, x),
+                                                assume(greaterEq(x, y))
+                                )
+                                .build();
+
+                return Stream.of(
+                                Arguments.of(dnfWithInput.call(x, q)),
+                                Arguments.of(not(dnfWithInput.call(x, q))),
+                                Arguments.of(y.assign(dnfWithInput.count(x, q))),
+                                Arguments.of(y.assign(dnfWithInputToAggregate.aggregateBy(z, INT_SUM, x, q, z)))
+                );
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithDataVariableOutput")
+        void boundDataParameterTest(Literal literal) {
+                var builder = Dnf.builder().parameter(x, ParameterDirection.OUT).clause(literal);
+                var dnf = assertDoesNotThrow(builder::build);
+                assertThat(dnf.getClauses().get(0).positiveVariables(), hasItem(x));
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithDataVariableOutput")
+        void boundTwiceDataParameterTest(Literal literal) {
+                var builder = Dnf.builder().parameter(x, ParameterDirection.IN).clause(literal);
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithDataVariableOutput")
+        void boundPrivateDataVariableOutputTest(Literal literal) {
+                var dnfWithInput = Dnf.builder("WithInput")
+                                .parameter(x, ParameterDirection.IN)
+                                .clause(assume(greaterEq(x, constant(24))))
+                                .build();
+                var builder = Dnf.builder().clause(dnfWithInput.call(x), literal);
+                var dnf = assertDoesNotThrow(builder::build);
+                assertThat(dnf.getClauses().get(0).positiveVariables(), hasItem(x));
+        }
+
+        @ParameterizedTest
+        @MethodSource("literalsWithDataVariableOutput")
+        void boundTwicePrivateDataVariableOutputTest(Literal literal) {
+                var builder = Dnf.builder().clause(x.assign(constant(27)), literal);
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        static Stream<Arguments> literalsWithDataVariableOutput() {
+                var dnfWithOutput = Dnf.builder("WithOutput")
+                                .parameter(q, ParameterDirection.OUT)
+                                .clause(personView.call(q))
+                                .build();
+                var dnfWithDataOutput = Dnf.builder("WithDataOutput")
+                                .parameter(y, ParameterDirection.OUT)
+                                .parameter(q, ParameterDirection.OUT)
+                                .clause(ageView.call(q, y))
+                                .build();
+                var dnfWithOutputToAggregate = Dnf.builder("WithDataOutputToAggregate")
+                                .parameter(q, ParameterDirection.OUT)
+                                .parameter(y, ParameterDirection.OUT)
+                                .clause(ageView.call(q, y))
+                                .build();
+
+                return Stream.of(
+                                Arguments.of(x.assign(constant(24))),
+                                Arguments.of(ageView.call(q, x)),
+                                Arguments.of(x.assign(personView.count(q))),
+                                Arguments.of(x.assign(ageView.aggregate(INT_SUM, q))),
+                                Arguments.of(dnfWithDataOutput.call(x, q)),
+                                Arguments.of(x.assign(dnfWithOutput.count(q))),
+                                Arguments.of(x.assign(dnfWithOutputToAggregate.aggregateBy(z, INT_SUM, q, z)))
+                );
+        }
+
+        private static Stream<Arguments> literalToClauseArgumentStream(Stream<Arguments> literalArgumentsStream) {
+                return literalArgumentsStream.map(arguments -> Arguments.of(List.of(arguments.get()[0])));
+        }
+}
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/literal/AggregationLiteralTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/literal/AggregationLiteralTest.java
new file mode 100644
index 00000000..35910e08
--- /dev/null
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/literal/AggregationLiteralTest.java
@@ -0,0 +1,88 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.literal;
+
+import org.junit.jupiter.api.Test;
+import tools.refinery.store.query.Constraint;
+import tools.refinery.store.query.dnf.Dnf;
+import tools.refinery.store.query.term.*;
+
+import java.util.List;
+import java.util.Set;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.containsInAnyOrder;
+import static org.hamcrest.Matchers.empty;
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static tools.refinery.store.query.literal.Literals.not;
+import static tools.refinery.store.query.term.int_.IntTerms.INT_SUM;
+import static tools.refinery.store.query.term.int_.IntTerms.constant;
+
+class AggregationLiteralTest {
+        private static final NodeVariable p = Variable.of("p");
+        private static final DataVariable<Integer> x = Variable.of("x", Integer.class);
+        private static final DataVariable<Integer> y = Variable.of("y", Integer.class);
+        private static final DataVariable<Integer> z = Variable.of("z", Integer.class);
+        private static final Constraint fakeConstraint = new Constraint() {
+                @Override
+                public String name() {
+                        return getClass().getName();
+                }
+
+                @Override
+                public List<Parameter> getParameters() {
+                        return List.of(
+                                        new Parameter(null, ParameterDirection.OUT),
+                                        new Parameter(Integer.class, ParameterDirection.OUT)
+                        );
+                }
+        };
+
+        @Test
+        void parameterDirectionTest() {
+                var literal = x.assign(fakeConstraint.aggregateBy(y, INT_SUM, p, y));
+                assertAll(
+                                () -> assertThat(literal.getOutputVariables(), containsInAnyOrder(x)),
+                                () -> assertThat(literal.getInputVariables(Set.of()), empty()),
+                                () -> assertThat(literal.getInputVariables(Set.of(p)), containsInAnyOrder(p)),
+                                () -> assertThat(literal.getPrivateVariables(Set.of()), containsInAnyOrder(p, y)),
+                                () -> assertThat(literal.getPrivateVariables(Set.of(p)), containsInAnyOrder(y))
+                );
+        }
+
+        @Test
+        void missingAggregationVariableTest() {
+                var aggregation = fakeConstraint.aggregateBy(y, INT_SUM, p, z);
+                assertThrows(IllegalArgumentException.class, () -> x.assign(aggregation));
+        }
+
+        @Test
+        void circularAggregationVariableTest() {
+                var aggregation = fakeConstraint.aggregateBy(x, INT_SUM, p, x);
+                assertThrows(IllegalArgumentException.class, () -> x.assign(aggregation));
+        }
+
+        @Test
+        void unboundTwiceVariableTest() {
+                var builder = Dnf.builder()
+                                .clause(
+                                                not(fakeConstraint.call(p, y)),
+                                                x.assign(fakeConstraint.aggregateBy(y, INT_SUM, p, y))
+                                );
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+
+        @Test
+        void unboundBoundVariableTest() {
+                var builder = Dnf.builder()
+                                .clause(
+                                                y.assign(constant(27)),
+                                                x.assign(fakeConstraint.aggregateBy(y, INT_SUM, p, y))
+                                );
+                assertThrows(IllegalArgumentException.class, builder::build);
+        }
+}
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/literal/CallLiteralTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/literal/CallLiteralTest.java
new file mode 100644
index 00000000..a01c6586
--- /dev/null
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/literal/CallLiteralTest.java
@@ -0,0 +1,94 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.literal;
+
+import org.junit.jupiter.api.Test;
+import tools.refinery.store.query.Constraint;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.Parameter;
+import tools.refinery.store.query.term.ParameterDirection;
+import tools.refinery.store.query.term.Variable;
+
+import java.util.List;
+import java.util.Set;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.containsInAnyOrder;
+import static org.hamcrest.Matchers.empty;
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static tools.refinery.store.query.literal.Literals.not;
+
+class CallLiteralTest {
+        private static final NodeVariable p = Variable.of("p");
+        private static final NodeVariable q = Variable.of("q");
+        private static final NodeVariable r = Variable.of("r");
+        private static final NodeVariable s = Variable.of("s");
+
+        private static final Constraint fakeConstraint = new Constraint() {
+                @Override
+                public String name() {
+                        return getClass().getName();
+                }
+
+                @Override
+                public List<Parameter> getParameters() {
+                        return List.of(
+                                        new Parameter(null, ParameterDirection.IN),
+                                        new Parameter(null, ParameterDirection.IN),
+                                        new Parameter(null, ParameterDirection.OUT),
+                                        new Parameter(null, ParameterDirection.OUT)
+                        );
+                }
+        };
+
+        @Test
+        void notRepeatedPositiveDirectionTest() {
+                var literal = fakeConstraint.call(p, q, r, s);
+                assertAll(
+                                () -> assertThat(literal.getOutputVariables(), containsInAnyOrder(r, s)),
+                                () -> assertThat(literal.getInputVariables(Set.of()), containsInAnyOrder(p, q)),
+                                () -> assertThat(literal.getInputVariables(Set.of(p, q, r)), containsInAnyOrder(p, q)),
+                                () -> assertThat(literal.getPrivateVariables(Set.of()), empty()),
+                                () -> assertThat(literal.getPrivateVariables(Set.of(p, q, r)), empty())
+                );
+        }
+
+        @Test
+        void notRepeatedNegativeDirectionTest() {
+                var literal = not(fakeConstraint.call(p, q, r, s));
+                assertAll(
+                                () -> assertThat(literal.getOutputVariables(), empty()),
+                                () -> assertThat(literal.getInputVariables(Set.of()), containsInAnyOrder(p, q)),
+                                () -> assertThat(literal.getInputVariables(Set.of(p, q, r)), containsInAnyOrder(p, q, r)),
+                                () -> assertThat(literal.getPrivateVariables(Set.of()), containsInAnyOrder(r, s)),
+                                () -> assertThat(literal.getPrivateVariables(Set.of(p, q, r)), containsInAnyOrder(s))
+                );
+        }
+
+        @Test
+        void repeatedPositiveDirectionTest() {
+                var literal = fakeConstraint.call(p, p, q, q);
+                assertAll(
+                                () -> assertThat(literal.getOutputVariables(), containsInAnyOrder(q)),
+                                () -> assertThat(literal.getInputVariables(Set.of()), containsInAnyOrder(p)),
+                                () -> assertThat(literal.getInputVariables(Set.of(p, q)), containsInAnyOrder(p)),
+                                () -> assertThat(literal.getPrivateVariables(Set.of()), empty()),
+                                () -> assertThat(literal.getPrivateVariables(Set.of(p, q)), empty())
+                );
+        }
+
+        @Test
+        void repeatedNegativeDirectionTest() {
+                var literal = not(fakeConstraint.call(p, p, q, q));
+                assertAll(
+                                () -> assertThat(literal.getOutputVariables(), empty()),
+                                () -> assertThat(literal.getInputVariables(Set.of()), containsInAnyOrder(p)),
+                                () -> assertThat(literal.getInputVariables(Set.of(p, q)), containsInAnyOrder(p, q)),
+                                () -> assertThat(literal.getPrivateVariables(Set.of()), containsInAnyOrder(q)),
+                                () -> assertThat(literal.getPrivateVariables(Set.of(p, q)), empty())
+                );
+        }
+}
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/term/TermSubstitutionTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/TermSubstitutionTest.java
new file mode 100644
index 00000000..1cbc101a
--- /dev/null
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/TermSubstitutionTest.java
@@ -0,0 +1,97 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+import tools.refinery.store.query.dnf.Dnf;
+import tools.refinery.store.query.equality.LiteralEqualityHelper;
+import tools.refinery.store.query.substitution.Substitution;
+import tools.refinery.store.query.term.bool.BoolTerms;
+import tools.refinery.store.query.term.int_.IntTerms;
+import tools.refinery.store.query.term.real.RealTerms;
+import tools.refinery.store.query.term.uppercardinality.UpperCardinalityTerms;
+import tools.refinery.store.representation.cardinality.UpperCardinality;
+
+import java.util.List;
+import java.util.stream.Stream;
+
+class TermSubstitutionTest {
+        private final static DataVariable<Integer> intA = Variable.of("intA", Integer.class);
+        private final static DataVariable<Integer> intB = Variable.of("intB", Integer.class);
+        private final static DataVariable<Double> realA = Variable.of("realA", Double.class);
+        private final static DataVariable<Double> realB = Variable.of("realB", Double.class);
+        private final static DataVariable<Boolean> boolA = Variable.of("boolA", Boolean.class);
+        private final static DataVariable<Boolean> boolB = Variable.of("boolB", Boolean.class);
+        private final static DataVariable<UpperCardinality> upperCardinalityA = Variable.of("upperCardinalityA",
+                        UpperCardinality.class);
+        private final static DataVariable<UpperCardinality> upperCardinalityB = Variable.of("upperCardinalityB",
+                        UpperCardinality.class);
+        private final static Substitution substitution = Substitution.builder()
+                        .put(intA, intB)
+                        .put(intB, intA)
+                        .put(realA, realB)
+                        .put(realB, realA)
+                        .put(boolA, boolB)
+                        .put(boolB, boolA)
+                        .put(upperCardinalityA, upperCardinalityB)
+                        .put(upperCardinalityB, upperCardinalityA)
+                        .build();
+
+        @ParameterizedTest
+        @MethodSource
+        void substitutionTest(AnyTerm term) {
+                var substitutedTerm1 = term.substitute(substitution);
+                Assertions.assertNotEquals(term, substitutedTerm1, "Original term is not equal to substituted term");
+                var helper = new LiteralEqualityHelper(Dnf::equals, List.of(), List.of());
+                Assertions.assertTrue(term.equalsWithSubstitution(helper, substitutedTerm1), "Terms are equal by helper");
+                // The {@link #substitution} is its own inverse.
+                var substitutedTerm2 = substitutedTerm1.substitute(substitution);
+                Assertions.assertEquals(term, substitutedTerm2, "Original term is not equal to back-substituted term");
+        }
+
+        static Stream<Arguments> substitutionTest() {
+                return Stream.of(
+                                Arguments.of(IntTerms.plus(intA)),
+                                Arguments.of(IntTerms.minus(intA)),
+                                Arguments.of(IntTerms.add(intA, intB)),
+                                Arguments.of(IntTerms.sub(intA, intB)),
+                                Arguments.of(IntTerms.mul(intA, intB)),
+                                Arguments.of(IntTerms.div(intA, intB)),
+                                Arguments.of(IntTerms.pow(intA, intB)),
+                                Arguments.of(IntTerms.min(intA, intB)),
+                                Arguments.of(IntTerms.max(intA, intB)),
+                                Arguments.of(IntTerms.eq(intA, intB)),
+                                Arguments.of(IntTerms.notEq(intA, intB)),
+                                Arguments.of(IntTerms.less(intA, intB)),
+                                Arguments.of(IntTerms.lessEq(intA, intB)),
+                                Arguments.of(IntTerms.greater(intA, intB)),
+                                Arguments.of(IntTerms.greaterEq(intA, intB)),
+                                Arguments.of(IntTerms.asInt(realA)),
+                                Arguments.of(RealTerms.plus(realA)),
+                                Arguments.of(RealTerms.minus(realA)),
+                                Arguments.of(RealTerms.add(realA, realB)),
+                                Arguments.of(RealTerms.sub(realA, realB)),
+                                Arguments.of(RealTerms.mul(realA, realB)),
+                                Arguments.of(RealTerms.div(realA, realB)),
+                                Arguments.of(RealTerms.pow(realA, realB)),
+                                Arguments.of(RealTerms.min(realA, realB)),
+                                Arguments.of(RealTerms.max(realA, realB)),
+                                Arguments.of(RealTerms.asReal(intA)),
+                                Arguments.of(BoolTerms.not(boolA)),
+                                Arguments.of(BoolTerms.and(boolA, boolB)),
+                                Arguments.of(BoolTerms.or(boolA, boolB)),
+                                Arguments.of(BoolTerms.xor(boolA, boolB)),
+                                Arguments.of(RealTerms.eq(realA, realB)),
+                                Arguments.of(UpperCardinalityTerms.add(upperCardinalityA, upperCardinalityB)),
+                                Arguments.of(UpperCardinalityTerms.mul(upperCardinalityA, upperCardinalityB)),
+                                Arguments.of(UpperCardinalityTerms.min(upperCardinalityA, upperCardinalityB)),
+                                Arguments.of(UpperCardinalityTerms.max(upperCardinalityA, upperCardinalityB))
+                );
+        }
+}
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/term/bool/BoolTermsEvaluateTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/bool/BoolTermsEvaluateTest.java
new file mode 100644
index 00000000..beff705e
--- /dev/null
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/bool/BoolTermsEvaluateTest.java
@@ -0,0 +1,75 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.bool;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+import tools.refinery.store.query.valuation.Valuation;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+
+class BoolTermsEvaluateTest {
+        @ParameterizedTest(name = "!{0} == {1}")
+        @CsvSource(value = {
+                        "false, true",
+                        "true, false",
+                        "null, null"
+        }, nullValues = "null")
+        void notTest(Boolean a, Boolean result) {
+                var term = BoolTerms.not(BoolTerms.constant(a));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "{0} && {1} == {2}")
+        @CsvSource(value = {
+                        "false, false, false",
+                        "false, true, false",
+                        "true, false, false",
+                        "true, true, true",
+                        "false, null, null",
+                        "null, false, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void andTest(Boolean a, Boolean b, Boolean result) {
+                var term = BoolTerms.and(BoolTerms.constant(a), BoolTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "{0} || {1} == {2}")
+        @CsvSource(value = {
+                        "false, false, false",
+                        "false, true, true",
+                        "true, false, true",
+                        "true, true, true",
+                        "true, null, null",
+                        "null, true, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void orTest(Boolean a, Boolean b, Boolean result) {
+                var term = BoolTerms.or(BoolTerms.constant(a), BoolTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "{0} ^^ {1} == {2}")
+        @CsvSource(value = {
+                        "false, false, false",
+                        "false, true, true",
+                        "true, false, true",
+                        "true, true, false",
+                        "false, null, null",
+                        "null, false, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void xorTest(Boolean a, Boolean b, Boolean result) {
+                var term = BoolTerms.xor(BoolTerms.constant(a), BoolTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+}
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/term/int_/IntTermsEvaluateTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/int_/IntTermsEvaluateTest.java
new file mode 100644
index 00000000..abe50d75
--- /dev/null
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/int_/IntTermsEvaluateTest.java
@@ -0,0 +1,259 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.int_;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.CsvSource;
+import org.junit.jupiter.params.provider.MethodSource;
+import tools.refinery.store.query.term.real.RealTerms;
+import tools.refinery.store.query.valuation.Valuation;
+
+import java.util.stream.Stream;
+
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+class IntTermsEvaluateTest {
+        @ParameterizedTest(name = "+{0} == {1}")
+        @CsvSource(value = {
+                        "2, 2",
+                        "null, null"
+        }, nullValues = "null")
+        void plusTest(Integer a, Integer result) {
+                var term = IntTerms.plus(IntTerms.constant(a));
+                assertThat(term.getType(), is(Integer.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "-{0} == {1}")
+        @CsvSource(value = {
+                        "2, -2",
+                        "null, null"
+        }, nullValues = "null")
+        void minusTest(Integer a, Integer result) {
+                var term = IntTerms.minus(IntTerms.constant(a));
+                assertThat(term.getType(), is(Integer.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "{0} + {1} == {2}")
+        @CsvSource(value = {
+                        "1, 2, 3",
+                        "null, 2, null",
+                        "1, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void addTest(Integer a, Integer b, Integer result) {
+                var term = IntTerms.add(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Integer.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "{0} - {1} == {2}")
+        @CsvSource(value = {
+                        "1, 3, -2",
+                        "null, 3, null",
+                        "1, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void subTest(Integer a, Integer b, Integer result) {
+                var term = IntTerms.sub(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Integer.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "{0} * {1} == {2}")
+        @CsvSource(value = {
+                        "2, 3, 6",
+                        "null, 3, null",
+                        "2, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void mulTest(Integer a, Integer b, Integer result) {
+                var term = IntTerms.mul(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Integer.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "{0} * {1} == {2}")
+        @CsvSource(value = {
+                        "6, 3, 2",
+                        "7, 3, 2",
+                        "6, 0, null",
+                        "null, 3, null",
+                        "6, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void divTest(Integer a, Integer b, Integer result) {
+                var term = IntTerms.div(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Integer.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "{0} ** {1} == {2}")
+        @CsvSource(value = {
+                        "1, 0, 1",
+                        "1, 3, 1",
+                        "1, -3, null",
+                        "2, 0, 1",
+                        "2, 2, 4",
+                        "2, 3, 8",
+                        "2, 4, 16",
+                        "2, 5, 32",
+                        "2, 6, 64",
+                        "2, -3, null",
+                        "null, 3, null",
+                        "2, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void powTest(Integer a, Integer b, Integer result) {
+                var term = IntTerms.pow(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Integer.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "min({0}, {1}) == {2}")
+        @CsvSource(value = {
+                        "1, 2, 1",
+                        "2, 1, 1",
+                        "null, 2, null",
+                        "1, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void minTest(Integer a, Integer b, Integer result) {
+                var term = IntTerms.min(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Integer.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "max({0}, {1}) == {2}")
+        @CsvSource(value = {
+                        "1, 2, 2",
+                        "2, 1, 2",
+                        "null, 2, null",
+                        "1, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void maxTest(Integer a, Integer b, Integer result) {
+                var term = IntTerms.max(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Integer.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "({0} == {1}) == {2}")
+        @CsvSource(value = {
+                        "1, 1, true",
+                        "1, 2, false",
+                        "null, 1, null",
+                        "1, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void eqTest(Integer a, Integer b, Boolean result) {
+                var term = IntTerms.eq(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "({0} != {1}) == {2}")
+        @CsvSource(value = {
+                        "1, 1, false",
+                        "1, 2, true",
+                        "null, 1, null",
+                        "1, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void notEqTest(Integer a, Integer b, Boolean result) {
+                var term = IntTerms.notEq(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "({0} < {1}) == {2}")
+        @CsvSource(value = {
+                        "1, -2, false",
+                        "1, 1, false",
+                        "1, 2, true",
+                        "null, 1, null",
+                        "1, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void lessTest(Integer a, Integer b, Boolean result) {
+                var term = IntTerms.less(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "({0} <= {1}) == {2}")
+        @CsvSource(value = {
+                        "1, -2, false",
+                        "1, 1, true",
+                        "1, 2, true",
+                        "null, 1, null",
+                        "1, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void lessEqTest(Integer a, Integer b, Boolean result) {
+                var term = IntTerms.lessEq(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "({0} > {1}) == {2}")
+        @CsvSource(value = {
+                        "1, -2, true",
+                        "1, 1, false",
+                        "1, 2, false",
+                        "null, 1, null",
+                        "1, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void greaterTest(Integer a, Integer b, Boolean result) {
+                var term = IntTerms.greater(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "({0} >= {1}) == {2}")
+        @CsvSource(value = {
+                        "1, -2, true",
+                        "1, 1, true",
+                        "1, 2, false",
+                        "null, 1, null",
+                        "1, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void greaterEqTest(Integer a, Integer b, Boolean result) {
+                var term = IntTerms.greaterEq(IntTerms.constant(a), IntTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "{0} as int == {1}")
+        @MethodSource
+        void asIntTest(Double a, Integer result) {
+                var term = IntTerms.asInt(RealTerms.constant(a));
+                assertThat(term.getType(), is(Integer.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        static Stream<Arguments> asIntTest() {
+                return Stream.of(
+                                Arguments.of(2.0, 2),
+                                Arguments.of(2.1, 2),
+                                Arguments.of(2.9, 2),
+                                Arguments.of(-2.0, -2),
+                                Arguments.of(-2.1, -2),
+                                Arguments.of(-2.9, -2),
+                                Arguments.of(0.0, 0),
+                                Arguments.of(-0.0, 0),
+                                Arguments.of(Double.POSITIVE_INFINITY, Integer.MAX_VALUE),
+                                Arguments.of(Double.NEGATIVE_INFINITY, Integer.MIN_VALUE),
+                                Arguments.of(Double.NaN, null),
+                                Arguments.of(null, null)
+                );
+        }
+}
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/term/real/RealTermEvaluateTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/real/RealTermEvaluateTest.java
new file mode 100644
index 00000000..6a8eebf1
--- /dev/null
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/real/RealTermEvaluateTest.java
@@ -0,0 +1,238 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.real;
+
+import org.hamcrest.Matcher;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+import tools.refinery.store.query.term.int_.IntTerms;
+import tools.refinery.store.query.valuation.Valuation;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.*;
+
+class RealTermEvaluateTest {
+        public static final double TOLERANCE = 1e-6;
+
+        private static Matcher<Double> closeToOrNull(Double expected) {
+                return expected == null ? nullValue(Double.class) : closeTo(expected, TOLERANCE);
+        }
+
+        @ParameterizedTest(name = "+{0} == {1}")
+        @CsvSource(value = {
+                        "2.5, 2.5",
+                        "null, null"
+        }, nullValues = "null")
+        void plusTest(Double a, Double result) {
+                var term = RealTerms.plus(RealTerms.constant(a));
+                assertThat(term.getType(), is(Double.class));
+                assertThat(term.evaluate(Valuation.empty()), closeToOrNull(result));
+        }
+
+        @ParameterizedTest(name = "-{0} == {1}")
+        @CsvSource(value = {
+                        "2.5, -2.5",
+                        "null, null"
+        }, nullValues = "null")
+        void minusTest(Double a, Double result) {
+                var term = RealTerms.minus(RealTerms.constant(a));
+                assertThat(term.getType(), is(Double.class));
+                assertThat(term.evaluate(Valuation.empty()), closeToOrNull(result));
+        }
+
+        @ParameterizedTest(name = "{0} + {1} == {2}")
+        @CsvSource(value = {
+                        "1.2, 2.3, 3.5",
+                        "null, 2.3, null",
+                        "1.2, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void addTest(Double a, Double b, Double result) {
+                var term = RealTerms.add(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Double.class));
+                assertThat(term.evaluate(Valuation.empty()), closeToOrNull(result));
+        }
+
+        @ParameterizedTest(name = "{0} - {1} == {2}")
+        @CsvSource(value = {
+                        "1.2, 3.4, -2.2",
+                        "null, 3.4, null",
+                        "1.2, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void subTest(Double a, Double b, Double result) {
+                var term = RealTerms.sub(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Double.class));
+                assertThat(term.evaluate(Valuation.empty()), closeToOrNull(result));
+        }
+
+        @ParameterizedTest(name = "{0} * {1} == {2}")
+        @CsvSource(value = {
+                        "2.3, 3.4, 7.82",
+                        "null, 3.4, null",
+                        "2.3, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void mulTest(Double a, Double b, Double result) {
+                var term = RealTerms.mul(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Double.class));
+                assertThat(term.evaluate(Valuation.empty()), closeToOrNull(result));
+        }
+
+        @ParameterizedTest(name = "{0} * {1} == {2}")
+        @CsvSource(value = {
+                        "7.82, 3.4, 2.3",
+                        "null, 3.4, null",
+                        "7.82, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void divTest(Double a, Double b, Double result) {
+                var term = RealTerms.div(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Double.class));
+                assertThat(term.evaluate(Valuation.empty()), closeToOrNull(result));
+        }
+
+        @ParameterizedTest(name = "{0} ** {1} == {2}")
+        @CsvSource(value = {
+                        "2.0, 6.0, 64.0",
+                        "null, 6.0, null",
+                        "2.0, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void powTest(Double a, Double b, Double result) {
+                var term = RealTerms.pow(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Double.class));
+                assertThat(term.evaluate(Valuation.empty()), closeToOrNull(result));
+        }
+
+        @ParameterizedTest(name = "min({0}, {1}) == {2}")
+        @CsvSource(value = {
+                        "1.5, 2.7, 1.5",
+                        "2.7, 1.5, 1.5",
+                        "null, 2.7, null",
+                        "1.5, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void minTest(Double a, Double b, Double result) {
+                var term = RealTerms.min(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Double.class));
+                assertThat(term.evaluate(Valuation.empty()), closeToOrNull(result));
+        }
+
+        @ParameterizedTest(name = "max({0}, {1}) == {2}")
+        @CsvSource(value = {
+                        "1.5, 2.7, 2.7",
+                        "2.7, 1.7, 2.7",
+                        "null, 2.7, null",
+                        "1.5, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void maxTest(Double a, Double b, Double result) {
+                var term = RealTerms.max(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Double.class));
+                assertThat(term.evaluate(Valuation.empty()), closeToOrNull(result));
+        }
+
+        @ParameterizedTest(name = "({0} == {1}) == {2}")
+        @CsvSource(value = {
+                        "1.5, 1.5, true",
+                        "1.5, 2.7, false",
+                        "null, 1.5, null",
+                        "1.5, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void eqTest(Double a, Double b, Boolean result) {
+                var term = RealTerms.eq(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "({0} != {1}) == {2}")
+        @CsvSource(value = {
+                        "1.5, 1.5, false",
+                        "1.5, 2.7, true",
+                        "null, 1.5, null",
+                        "1.5, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void notEqTest(Double a, Double b, Boolean result) {
+                var term = RealTerms.notEq(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "({0} < {1}) == {2}")
+        @CsvSource(value = {
+                        "1.5, -2.7, false",
+                        "1.5, 1.5, false",
+                        "1.5, 2.7, true",
+                        "null, 1.5, null",
+                        "1.5, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void lessTest(Double a, Double b, Boolean result) {
+                var term = RealTerms.less(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "({0} <= {1}) == {2}")
+        @CsvSource(value = {
+                        "1.5, -2.7, false",
+                        "1.5, 1.5, true",
+                        "1.5, 2.7, true",
+                        "null, 1.5, null",
+                        "1.5, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void lessEqTest(Double a, Double b, Boolean result) {
+                var term = RealTerms.lessEq(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "({0} > {1}) == {2}")
+        @CsvSource(value = {
+                        "1.5, -2.7, true",
+                        "1.5, 1.5, false",
+                        "1.5, 2.7, false",
+                        "null, 1.5, null",
+                        "1.5, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void greaterTest(Double a, Double b, Boolean result) {
+                var term = RealTerms.greater(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "({0} >= {1}) == {2}")
+        @CsvSource(value = {
+                        "1.5, -2.7, true",
+                        "1.5, 1.5, true",
+                        "1.5, 2.7, false",
+                        "null, 1.5, null",
+                        "1.5, null, null",
+                        "null, null, null"
+        }, nullValues = "null")
+        void greaterEqTest(Double a, Double b, Boolean result) {
+                var term = RealTerms.greaterEq(RealTerms.constant(a), RealTerms.constant(b));
+                assertThat(term.getType(), is(Boolean.class));
+                assertThat(term.evaluate(Valuation.empty()), is(result));
+        }
+
+        @ParameterizedTest(name = "{0} as real == {1}")
+        @CsvSource(value = {
+                        "0, 0.0",
+                        "5, 5.0",
+                        "null, null"
+        }, nullValues = "null")
+        void asRealTest(Integer a, Double result) {
+                var term = RealTerms.asReal(IntTerms.constant(a));
+                assertThat(term.getType(), is(Double.class));
+                assertThat(term.evaluate(Valuation.empty()), closeToOrNull(result));
+        }
+}
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/internal/cardinality/UpperCardinalitySumAggregationOperatorStreamTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalitySumAggregatorStreamTest.java
index c529117e..31baf36e 100644
--- a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/internal/cardinality/UpperCardinalitySumAggregationOperatorStreamTest.java
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalitySumAggregatorStreamTest.java
@@ -1,4 +1,9 @@
-package tools.refinery.store.query.viatra.internal.cardinality;
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.uppercardinality;
 
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.Arguments;
@@ -10,14 +15,14 @@ import java.util.List;
 import java.util.stream.Stream;
 
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.is;
 
-class UpperCardinalitySumAggregationOperatorStreamTest {
+class UpperCardinalitySumAggregatorStreamTest {
         @ParameterizedTest
         @MethodSource
         void testStream(List<UpperCardinality> list, UpperCardinality expected) {
-                var result = UpperCardinalitySumAggregationOperator.INSTANCE.aggregateStream(list.stream());
-                assertThat(result, equalTo(expected));
+                var result = UpperCardinalitySumAggregator.INSTANCE.aggregateStream(list.stream());
+                assertThat(result, is(expected));
         }
 
         static Stream<Arguments> testStream() {
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalitySumAggregatorTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalitySumAggregatorTest.java
new file mode 100644
index 00000000..780cd0ab
--- /dev/null
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalitySumAggregatorTest.java
@@ -0,0 +1,80 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.uppercardinality;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import tools.refinery.store.query.term.StatefulAggregate;
+import tools.refinery.store.representation.cardinality.UpperCardinalities;
+import tools.refinery.store.representation.cardinality.UpperCardinality;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+
+class UpperCardinalitySumAggregatorTest {
+        private StatefulAggregate<UpperCardinality, UpperCardinality> accumulator;
+
+        @BeforeEach
+        void beforeEach() {
+                accumulator = UpperCardinalitySumAggregator.INSTANCE.createEmptyAggregate();
+        }
+
+        @Test
+        void emptyAggregationTest() {
+                assertThat(accumulator.getResult(), is(UpperCardinality.of(0)));
+        }
+
+        @Test
+        void singleBoundedTest() {
+                accumulator.add(UpperCardinality.of(3));
+                assertThat(accumulator.getResult(), is(UpperCardinality.of(3)));
+        }
+
+        @Test
+        void multipleBoundedTest() {
+                accumulator.add(UpperCardinality.of(2));
+                accumulator.add(UpperCardinality.of(3));
+                assertThat(accumulator.getResult(), is(UpperCardinality.of(5)));
+        }
+
+        @Test
+        void singleUnboundedTest() {
+                accumulator.add(UpperCardinalities.UNBOUNDED);
+                assertThat(accumulator.getResult(), is(UpperCardinalities.UNBOUNDED));
+        }
+
+        @Test
+        void multipleUnboundedTest() {
+                accumulator.add(UpperCardinalities.UNBOUNDED);
+                accumulator.add(UpperCardinalities.UNBOUNDED);
+                assertThat(accumulator.getResult(), is(UpperCardinalities.UNBOUNDED));
+        }
+
+        @Test
+        void removeBoundedTest() {
+                accumulator.add(UpperCardinality.of(2));
+                accumulator.add(UpperCardinality.of(3));
+                accumulator.remove(UpperCardinality.of(2));
+                assertThat(accumulator.getResult(), is(UpperCardinality.of(3)));
+        }
+
+        @Test
+        void removeAllUnboundedTest() {
+                accumulator.add(UpperCardinalities.UNBOUNDED);
+                accumulator.add(UpperCardinality.of(3));
+                accumulator.remove(UpperCardinalities.UNBOUNDED);
+                assertThat(accumulator.getResult(), is(UpperCardinality.of(3)));
+        }
+
+        @Test
+        void removeSomeUnboundedTest() {
+                accumulator.add(UpperCardinalities.UNBOUNDED);
+                accumulator.add(UpperCardinalities.UNBOUNDED);
+                accumulator.add(UpperCardinality.of(3));
+                accumulator.remove(UpperCardinalities.UNBOUNDED);
+                assertThat(accumulator.getResult(), is(UpperCardinalities.UNBOUNDED));
+        }
+}
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityTermsEvaluateTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityTermsEvaluateTest.java
new file mode 100644
index 00000000..9d0f3bde
--- /dev/null
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/term/uppercardinality/UpperCardinalityTermsEvaluateTest.java
@@ -0,0 +1,104 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.term.uppercardinality;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+import tools.refinery.store.query.valuation.Valuation;
+import tools.refinery.store.representation.cardinality.UpperCardinalities;
+import tools.refinery.store.representation.cardinality.UpperCardinality;
+
+import java.util.stream.Stream;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+
+class UpperCardinalityTermsEvaluateTest {
+        @ParameterizedTest(name = "min({0}, {1}) == {2}")
+        @MethodSource
+        void minTest(UpperCardinality a, UpperCardinality b, UpperCardinality expected) {
+                var term = UpperCardinalityTerms.min(UpperCardinalityTerms.constant(a), UpperCardinalityTerms.constant(b));
+                assertThat(term.getType(), is(UpperCardinality.class));
+                assertThat(term.evaluate(Valuation.empty()), is(expected));
+        }
+
+        static Stream<Arguments> minTest() {
+                return Stream.of(
+                                Arguments.of(UpperCardinality.of(0), UpperCardinality.of(0), UpperCardinality.of(0)),
+                                Arguments.of(UpperCardinality.of(0), UpperCardinality.of(1), UpperCardinality.of(0)),
+                                Arguments.of(UpperCardinality.of(1), UpperCardinality.of(0), UpperCardinality.of(0)),
+                                Arguments.of(UpperCardinality.of(0), UpperCardinalities.UNBOUNDED, UpperCardinality.of(0)),
+                                Arguments.of(UpperCardinalities.UNBOUNDED, UpperCardinality.of(0), UpperCardinality.of(0)),
+                                Arguments.of(UpperCardinalities.UNBOUNDED, UpperCardinalities.UNBOUNDED, UpperCardinalities.UNBOUNDED),
+                                Arguments.of(UpperCardinality.of(1), null, null),
+                                Arguments.of(null, UpperCardinality.of(1), null),
+                                Arguments.of(null, null, null)
+                );
+        }
+
+        @ParameterizedTest(name = "max({0}, {1}) == {2}")
+        @MethodSource
+        void maxTest(UpperCardinality a, UpperCardinality b, UpperCardinality expected) {
+                var term = UpperCardinalityTerms.max(UpperCardinalityTerms.constant(a), UpperCardinalityTerms.constant(b));
+                assertThat(term.getType(), is(UpperCardinality.class));
+                assertThat(term.evaluate(Valuation.empty()), is(expected));
+        }
+
+        static Stream<Arguments> maxTest() {
+                return Stream.of(
+                                Arguments.of(UpperCardinality.of(0), UpperCardinality.of(0), UpperCardinality.of(0)),
+                                Arguments.of(UpperCardinality.of(0), UpperCardinality.of(1), UpperCardinality.of(1)),
+                                Arguments.of(UpperCardinality.of(1), UpperCardinality.of(0), UpperCardinality.of(1)),
+                                Arguments.of(UpperCardinality.of(0), UpperCardinalities.UNBOUNDED, UpperCardinalities.UNBOUNDED),
+                                Arguments.of(UpperCardinalities.UNBOUNDED, UpperCardinality.of(0), UpperCardinalities.UNBOUNDED),
+                                Arguments.of(UpperCardinalities.UNBOUNDED, UpperCardinalities.UNBOUNDED, UpperCardinalities.UNBOUNDED),
+                                Arguments.of(UpperCardinality.of(1), null, null),
+                                Arguments.of(null, UpperCardinality.of(1), null),
+                                Arguments.of(null, null, null)
+                );
+        }
+
+        @ParameterizedTest(name = "{0} + {1} == {2}")
+        @MethodSource
+        void addTest(UpperCardinality a, UpperCardinality b, UpperCardinality expected) {
+                var term = UpperCardinalityTerms.add(UpperCardinalityTerms.constant(a), UpperCardinalityTerms.constant(b));
+                assertThat(term.getType(), is(UpperCardinality.class));
+                assertThat(term.evaluate(Valuation.empty()), is(expected));
+        }
+
+        static Stream<Arguments> addTest() {
+                return Stream.of(
+                                Arguments.of(UpperCardinality.of(2), UpperCardinality.of(3), UpperCardinality.of(5)),
+                                Arguments.of(UpperCardinality.of(2), UpperCardinalities.UNBOUNDED, UpperCardinalities.UNBOUNDED),
+                                Arguments.of(UpperCardinalities.UNBOUNDED, UpperCardinality.of(2), UpperCardinalities.UNBOUNDED),
+                                Arguments.of(UpperCardinalities.UNBOUNDED, UpperCardinalities.UNBOUNDED, UpperCardinalities.UNBOUNDED),
+                                Arguments.of(UpperCardinality.of(1), null, null),
+                                Arguments.of(null, UpperCardinality.of(1), null),
+                                Arguments.of(null, null, null)
+                );
+        }
+
+        @ParameterizedTest(name = "{0} * {1} == {2}")
+        @MethodSource
+        void mulTest(UpperCardinality a, UpperCardinality b, UpperCardinality expected) {
+                var term = UpperCardinalityTerms.mul(UpperCardinalityTerms.constant(a), UpperCardinalityTerms.constant(b));
+                assertThat(term.getType(), is(UpperCardinality.class));
+                assertThat(term.evaluate(Valuation.empty()), is(expected));
+        }
+
+        static Stream<Arguments> mulTest() {
+                return Stream.of(
+                                Arguments.of(UpperCardinality.of(2), UpperCardinality.of(3), UpperCardinality.of(6)),
+                                Arguments.of(UpperCardinality.of(2), UpperCardinalities.UNBOUNDED, UpperCardinalities.UNBOUNDED),
+                                Arguments.of(UpperCardinalities.UNBOUNDED, UpperCardinality.of(2), UpperCardinalities.UNBOUNDED),
+                                Arguments.of(UpperCardinalities.UNBOUNDED, UpperCardinalities.UNBOUNDED, UpperCardinalities.UNBOUNDED),
+                                Arguments.of(UpperCardinality.of(1), null, null),
+                                Arguments.of(null, UpperCardinality.of(1), null),
+                                Arguments.of(null, null, null)
+                );
+        }
+}
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/tests/StructurallyEqualToRawTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/tests/StructurallyEqualToRawTest.java
new file mode 100644
index 00000000..d447e99c
--- /dev/null
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/tests/StructurallyEqualToRawTest.java
@@ -0,0 +1,159 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.tests;
+
+import org.junit.jupiter.api.Test;
+import tools.refinery.store.query.dnf.Dnf;
+import tools.refinery.store.query.dnf.SymbolicParameter;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.ParameterDirection;
+import tools.refinery.store.query.term.Variable;
+import tools.refinery.store.query.view.AnySymbolView;
+import tools.refinery.store.query.view.KeyOnlyView;
+import tools.refinery.store.representation.Symbol;
+
+import java.util.List;
+
+import static org.hamcrest.CoreMatchers.containsString;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.allOf;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static tools.refinery.store.query.tests.QueryMatchers.structurallyEqualTo;
+
+class StructurallyEqualToRawTest {
+        private static final Symbol<Boolean> person = Symbol.of("Person", 1);
+        private static final Symbol<Boolean> friend = Symbol.of("friend", 2);
+        private static final AnySymbolView personView = new KeyOnlyView<>(person);
+        private static final AnySymbolView friendView = new KeyOnlyView<>(friend);
+        private static final NodeVariable p = Variable.of("p");
+        private static final NodeVariable q = Variable.of("q");
+
+        @Test
+        void flatEqualsTest() {
+                var actual = Dnf.builder("Actual").parameters(p).clause(personView.call(p)).build();
+
+                assertThat(actual, structurallyEqualTo(
+                                List.of(new SymbolicParameter(q, ParameterDirection.OUT)),
+                                List.of(List.of(personView.call(q)))
+                ));
+        }
+
+        @Test
+        void flatNotEqualsTest() {
+                var actual = Dnf.builder("Actual").parameters(p).clause(friendView.call(p, q)).build();
+
+                var assertion = structurallyEqualTo(
+                                List.of(new SymbolicParameter(q, ParameterDirection.OUT)),
+                                List.of(List.of(friendView.call(q, q)))
+                );
+                assertThrows(AssertionError.class, () -> assertThat(actual, assertion));
+        }
+
+        @Test
+        void deepEqualsTest() {
+                var actual = Dnf.builder("Actual").parameters(q).clause(
+                                Dnf.builder("Actual2").parameters(p).clause(personView.call(p)).build().call(q)
+                ).build();
+
+                assertThat(actual, structurallyEqualTo(
+                                List.of(new SymbolicParameter(q, ParameterDirection.OUT)),
+                                List.of(
+                                                List.of(
+                                                                Dnf.builder("Expected2").parameters(p).clause(personView.call(p)).build().call(q)
+                                                )
+                                )
+                ));
+        }
+
+        @Test
+        void deepNotEqualsTest() {
+                var actual = Dnf.builder("Actual").parameter(q).clause(
+                                Dnf.builder("Actual2").parameters(p).clause(friendView.call(p, q)).build().call(q)
+                ).build();
+
+                var assertion = structurallyEqualTo(
+                                List.of(new SymbolicParameter(q, ParameterDirection.OUT)),
+                                List.of(
+                                                List.of(
+                                                                Dnf.builder("Expected2")
+                                                                                .parameters(p)
+                                                                                .clause(friendView.call(p, p))
+                                                                                .build()
+                                                                                .call(q)
+                                                )
+                                )
+                );
+                var error = assertThrows(AssertionError.class, () -> assertThat(actual, assertion));
+                assertThat(error.getMessage(), allOf(containsString("Expected2"), containsString("Actual2")));
+        }
+
+        @Test
+        void parameterListLengthMismatchTest() {
+                var actual = Dnf.builder("Actual").parameters(p, q).clause(
+                                friendView.call(p, q)
+                ).build();
+
+                var assertion = structurallyEqualTo(
+                                List.of(new SymbolicParameter(p, ParameterDirection.OUT)),
+                                List.of(List.of(friendView.call(p, p)))
+                );
+
+                assertThrows(AssertionError.class, () -> assertThat(actual, assertion));
+        }
+
+        @Test
+        void parameterDirectionMismatchTest() {
+                var actual = Dnf.builder("Actual").parameter(p, ParameterDirection.IN).clause(
+                                personView.call(p)
+                ).build();
+
+                var assertion = structurallyEqualTo(
+                                List.of(new SymbolicParameter(p, ParameterDirection.OUT)),
+                                List.of(List.of(personView.call(p)))
+                );
+
+                assertThrows(AssertionError.class, () -> assertThat(actual, assertion));
+        }
+
+        @Test
+        void clauseCountMismatchTest() {
+                var actual = Dnf.builder("Actual").parameters(p, q).clause(
+                                friendView.call(p, q)
+                ).build();
+
+                var assertion = structurallyEqualTo(
+                                List.of(
+                                                new SymbolicParameter(p, ParameterDirection.OUT),
+                                                new SymbolicParameter(q, ParameterDirection.OUT)
+                                ),
+                                List.of(
+                                                List.of(friendView.call(p, q)),
+                                                List.of(friendView.call(q, p))
+                                )
+                );
+
+                assertThrows(AssertionError.class, () -> assertThat(actual, assertion));
+        }
+
+        @Test
+        void literalCountMismatchTest() {
+                var actual = Dnf.builder("Actual").parameters(p, q).clause(
+                                friendView.call(p, q)
+                ).build();
+
+                var assertion = structurallyEqualTo(
+                                List.of(
+                                                new SymbolicParameter(p, ParameterDirection.OUT),
+                                                new SymbolicParameter(q, ParameterDirection.OUT)
+                                ),
+                                List.of(
+                                                List.of(friendView.call(p, q), friendView.call(q, p))
+                                )
+                );
+
+                assertThrows(AssertionError.class, () -> assertThat(actual, assertion));
+        }
+}
diff --git a/subprojects/store-query/src/test/java/tools/refinery/store/query/tests/StructurallyEqualToTest.java b/subprojects/store-query/src/test/java/tools/refinery/store/query/tests/StructurallyEqualToTest.java
index a61e2b65..f716b805 100644
--- a/subprojects/store-query/src/test/java/tools/refinery/store/query/tests/StructurallyEqualToTest.java
+++ b/subprojects/store-query/src/test/java/tools/refinery/store/query/tests/StructurallyEqualToTest.java
@@ -1,9 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.tests;
 
 import org.junit.jupiter.api.Test;
 import tools.refinery.store.query.dnf.Dnf;
+import tools.refinery.store.query.term.NodeVariable;
+import tools.refinery.store.query.term.ParameterDirection;
 import tools.refinery.store.query.term.Variable;
-import tools.refinery.store.query.view.KeyOnlyRelationView;
+import tools.refinery.store.query.view.AnySymbolView;
+import tools.refinery.store.query.view.KeyOnlyView;
 import tools.refinery.store.representation.Symbol;
 
 import static org.hamcrest.CoreMatchers.containsString;
@@ -12,13 +20,15 @@ import static org.junit.jupiter.api.Assertions.assertThrows;
 import static tools.refinery.store.query.tests.QueryMatchers.structurallyEqualTo;
 
 class StructurallyEqualToTest {
+        private static final Symbol<Boolean> person = Symbol.of("Person", 1);
+        private static final Symbol<Boolean> friend = Symbol.of("friend", 2);
+        private static final AnySymbolView personView = new KeyOnlyView<>(person);
+        private static final AnySymbolView friendView = new KeyOnlyView<>(friend);
+        private static final NodeVariable p = Variable.of("p");
+        private static final NodeVariable q = Variable.of("q");
+
         @Test
         void flatEqualsTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-
                 var expected = Dnf.builder("Expected").parameters(q).clause(personView.call(q)).build();
                 var actual = Dnf.builder("Actual").parameters(p).clause(personView.call(p)).build();
 
@@ -27,13 +37,8 @@ class StructurallyEqualToTest {
 
         @Test
         void flatNotEqualsTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-
-                var expected = Dnf.builder("Expected").parameters(q).clause(personView.call(q)).build();
-                var actual = Dnf.builder("Actual").parameters(p).clause(personView.call(q)).build();
+                var expected = Dnf.builder("Expected").parameters(q).clause(friendView.call(q, q)).build();
+                var actual = Dnf.builder("Actual").parameters(p).clause(friendView.call(p, q)).build();
 
                 var assertion = structurallyEqualTo(expected);
                 assertThrows(AssertionError.class, () -> assertThat(actual, assertion));
@@ -41,11 +46,6 @@ class StructurallyEqualToTest {
 
         @Test
         void deepEqualsTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-
                 var expected = Dnf.builder("Expected").parameters(q).clause(
                                 Dnf.builder("Expected2").parameters(p).clause(personView.call(p)).build().call(q)
                 ).build();
@@ -58,20 +58,70 @@ class StructurallyEqualToTest {
 
         @Test
         void deepNotEqualsTest() {
-                var p = Variable.of("p");
-                var q = Variable.of("q");
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var personView = new KeyOnlyRelationView<>(person);
-
                 var expected = Dnf.builder("Expected").parameters(q).clause(
-                                Dnf.builder("Expected2").parameters(p).clause(personView.call(p)).build().call(q)
+                                Dnf.builder("Expected2").parameters(p).clause(friendView.call(p, p)).build().call(q)
                 ).build();
-                var actual = Dnf.builder("Actual").parameters(q).clause(
-                                Dnf.builder("Actual2").parameters(p).clause(personView.call(q)).build().call(q)
+                var actual = Dnf.builder("Actual").parameter(q).clause(
+                                Dnf.builder("Actual2").parameters(p).clause(friendView.call(p, q)).build().call(q)
                 ).build();
 
                 var assertion = structurallyEqualTo(expected);
                 var error = assertThrows(AssertionError.class, () -> assertThat(actual, assertion));
                 assertThat(error.getMessage(), containsString(" called from Expected/1 "));
         }
+
+        @Test
+        void parameterListLengthMismatchTest() {
+                var expected = Dnf.builder("Expected").parameter(p).clause(
+                                friendView.call(p, p)
+                ).build();
+                var actual = Dnf.builder("Actual").parameters(p, q).clause(
+                                friendView.call(p, q)
+                ).build();
+
+                var assertion = structurallyEqualTo(expected);
+                assertThrows(AssertionError.class, () -> assertThat(actual, assertion));
+        }
+
+        @Test
+        void parameterDirectionMismatchTest() {
+                var expected = Dnf.builder("Expected").parameter(p, ParameterDirection.OUT).clause(
+                                personView.call(p)
+                ).build();
+                var actual = Dnf.builder("Actual").parameter(p, ParameterDirection.IN).clause(
+                                personView.call(p)
+                ).build();
+
+                var assertion = structurallyEqualTo(expected);
+                assertThrows(AssertionError.class, () -> assertThat(actual, assertion));
+        }
+
+        @Test
+        void clauseCountMismatchTest() {
+                var expected = Dnf.builder("Expected")
+                                .parameters(p, q)
+                                .clause(friendView.call(p, q))
+                                .clause(friendView.call(q, p))
+                                .build();
+                var actual = Dnf.builder("Actual").parameters(p, q).clause(
+                                friendView.call(p, q)
+                ).build();
+
+                var assertion = structurallyEqualTo(expected);
+                assertThrows(AssertionError.class, () -> assertThat(actual, assertion));
+        }
+
+        @Test
+        void literalCountMismatchTest() {
+                var expected = Dnf.builder("Expected").parameters(p, q).clause(
+                                friendView.call(p, q),
+                                friendView.call(q, p)
+                ).build();
+                var actual = Dnf.builder("Actual").parameters(p, q).clause(
+                                friendView.call(p, q)
+                ).build();
+
+                var assertion = structurallyEqualTo(expected);
+                assertThrows(AssertionError.class, () -> assertThat(actual, assertion));
+        }
 }
diff --git a/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/MismatchDescribingDnfEqualityChecker.java b/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/MismatchDescribingDnfEqualityChecker.java
index 685957c9..6a3301b3 100644
--- a/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/MismatchDescribingDnfEqualityChecker.java
+++ b/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/MismatchDescribingDnfEqualityChecker.java
@@ -1,27 +1,52 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.tests;
 
 import org.hamcrest.Description;
+import tools.refinery.store.query.dnf.Dnf;
+import tools.refinery.store.query.dnf.SymbolicParameter;
 import tools.refinery.store.query.equality.DeepDnfEqualityChecker;
+import tools.refinery.store.query.literal.Literal;
+
+import java.util.List;
 
 class MismatchDescribingDnfEqualityChecker extends DeepDnfEqualityChecker {
         private final Description description;
-        private boolean described;
+        private boolean raw;
+        private boolean needsDescription = true;
 
         MismatchDescribingDnfEqualityChecker(Description description) {
                 this.description = description;
         }
 
-        public boolean isDescribed() {
-                return described;
+        public boolean needsDescription() {
+                return needsDescription;
+        }
+
+        @Override
+        public boolean dnfEqualRaw(List<SymbolicParameter> symbolicParameters, List<? extends List<? extends Literal>> clauses, Dnf other) {
+                try {
+                        raw = true;
+                        boolean result = super.dnfEqualRaw(symbolicParameters, clauses, other);
+                        if (!result && needsDescription) {
+                                description.appendText("was ").appendText(other.toDefinitionString());
+                        }
+                        return false;
+                } finally {
+                        raw = false;
+                }
         }
 
         @Override
         protected boolean doCheckEqual(Pair pair) {
                 boolean result = super.doCheckEqual(pair);
-                if (!result && !described) {
+                if (!result && needsDescription) {
                         describeMismatch(pair);
                         // Only describe the first found (innermost) mismatch.
-                        described = true;
+                        needsDescription = false;
                 }
                 return result;
         }
@@ -29,12 +54,12 @@ class MismatchDescribingDnfEqualityChecker extends DeepDnfEqualityChecker {
         private void describeMismatch(Pair pair) {
                 var inProgress = getInProgress();
                 int size = inProgress.size();
-                if (size <= 1) {
-                        description.appendText("was ").appendText(pair.left().toDefinitionString());
+                if (size <= 1 && !raw) {
+                        description.appendText("was ").appendText(pair.right().toDefinitionString());
                         return;
                 }
                 var last = inProgress.get(size - 1);
-                description.appendText("expected ").appendText(last.right().toDefinitionString());
+                description.appendText("expected ").appendText(last.left().toDefinitionString());
                 for (int i = size - 2; i >= 0; i--) {
                         description.appendText(" called from ").appendText(inProgress.get(i).left().toString());
                 }
diff --git a/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/QueryMatchers.java b/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/QueryMatchers.java
index bf1c1b74..cd449a6a 100644
--- a/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/QueryMatchers.java
+++ b/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/QueryMatchers.java
@@ -1,14 +1,46 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.tests;
 
 import org.hamcrest.Matcher;
 import tools.refinery.store.query.dnf.Dnf;
+import tools.refinery.store.query.dnf.SymbolicParameter;
+import tools.refinery.store.query.literal.Literal;
+
+import java.util.List;
 
 public final class QueryMatchers {
         private QueryMatchers() {
                 throw new IllegalStateException("This is a static utility class and should not be instantiated directly");
         }
 
+        /**
+         * Compare two {@link Dnf} instances up to renaming of variables.
+         *
+         * @param expected The expected {@link Dnf} instance.
+         * @return A Hamcrest matcher for equality up to renaming of variables.
+         */
         public static Matcher<Dnf> structurallyEqualTo(Dnf expected) {
                 return new StructurallyEqualTo(expected);
         }
+
+        /**
+         * Compare a {@link Dnf} instance to another predicate in DNF form without constructing it.
+         * <p>
+         * This matcher should be used instead of {@link #structurallyEqualTo(Dnf)} when the validation and
+         * pre-processing associated with the {@link Dnf} constructor, i.e., validation of parameter directions,
+         * topological sorting of literals, and the reduction of trivial predicates is not desired. In particular, this
+         * matcher can be used to test for exact order of literal after pre-processing.
+         *
+         * @param expectedSymbolicParameters The expected list of symbolic parameters.
+         * @param expectedLiterals The expected clauses. Each clause is represented by a list of literals.
+         * @return A Hamcrest matcher for equality up to renaming of variables.
+         */
+        public static Matcher<Dnf> structurallyEqualTo(List<SymbolicParameter> expectedSymbolicParameters,
+                                                                                                   List<? extends List<? extends Literal>> expectedLiterals) {
+                return new StructurallyEqualToRaw(expectedSymbolicParameters, expectedLiterals);
+        }
 }
diff --git a/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/StructurallyEqualTo.java b/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/StructurallyEqualTo.java
index a9a78f88..86149141 100644
--- a/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/StructurallyEqualTo.java
+++ b/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/StructurallyEqualTo.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.query.tests;
 
 import org.hamcrest.Description;
@@ -24,7 +29,7 @@ public class StructurallyEqualTo extends TypeSafeMatcher<Dnf> {
                 if (describingChecker.dnfEqual(expected, item)) {
                         throw new IllegalStateException("Mismatched Dnf was matching on repeated comparison");
                 }
-                if (!describingChecker.isDescribed()) {
+                if (describingChecker.needsDescription()) {
                         super.describeMismatchSafely(item, mismatchDescription);
                 }
         }
diff --git a/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/StructurallyEqualToRaw.java b/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/StructurallyEqualToRaw.java
new file mode 100644
index 00000000..2f8c2944
--- /dev/null
+++ b/subprojects/store-query/src/testFixtures/java/tools/refinery/store/query/tests/StructurallyEqualToRaw.java
@@ -0,0 +1,51 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.query.tests;
+
+import org.hamcrest.Description;
+import org.hamcrest.TypeSafeMatcher;
+import tools.refinery.store.query.dnf.Dnf;
+import tools.refinery.store.query.dnf.SymbolicParameter;
+import tools.refinery.store.query.equality.DeepDnfEqualityChecker;
+import tools.refinery.store.query.literal.Literal;
+
+import java.util.List;
+
+public class StructurallyEqualToRaw extends TypeSafeMatcher<Dnf> {
+        private final List<SymbolicParameter> expectedSymbolicParameters;
+        private final List<? extends List<? extends Literal>> expectedClauses;
+
+        public StructurallyEqualToRaw(List<SymbolicParameter> expectedSymbolicParameters,
+                                                                  List<? extends List<? extends Literal>> expectedClauses) {
+                this.expectedSymbolicParameters = expectedSymbolicParameters;
+                this.expectedClauses = expectedClauses;
+        }
+
+        @Override
+        protected boolean matchesSafely(Dnf item) {
+                var checker = new DeepDnfEqualityChecker();
+                return checker.dnfEqualRaw(expectedSymbolicParameters, expectedClauses, item);
+        }
+
+        @Override
+        protected void describeMismatchSafely(Dnf item, Description mismatchDescription) {
+                var describingChecker = new MismatchDescribingDnfEqualityChecker(mismatchDescription);
+                if (describingChecker.dnfEqualRaw(expectedSymbolicParameters, expectedClauses, item)) {
+                        throw new IllegalStateException("Mismatched Dnf was matching on repeated comparison");
+                }
+                if (describingChecker.needsDescription()) {
+                        super.describeMismatchSafely(item, mismatchDescription);
+                }
+        }
+
+        @Override
+        public void describeTo(Description description) {
+                description.appendText("structurally equal to ")
+                                .appendValueList("(", ", ", ")", expectedSymbolicParameters)
+                                .appendText(" <-> ")
+                                .appendValueList("", ", ", ".", expectedClauses);
+        }
+}
diff --git a/subprojects/store-reasoning/build.gradle b/subprojects/store-reasoning/build.gradle
deleted file mode 100644
index cb440d9f..00000000
--- a/subprojects/store-reasoning/build.gradle
+++ /dev/null
@@ -1,7 +0,0 @@
-plugins {
-        id 'refinery-java-library'
-}
-
-dependencies {
-        api project(':refinery-store-query')
-}
diff --git a/subprojects/store-reasoning/build.gradle.kts b/subprojects/store-reasoning/build.gradle.kts
new file mode 100644
index 00000000..abad0491
--- /dev/null
+++ b/subprojects/store-reasoning/build.gradle.kts
@@ -0,0 +1,13 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+plugins {
+        id("tools.refinery.gradle.java-library")
+}
+
+dependencies {
+        api(project(":refinery-store-query"))
+}
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/AnyPartialInterpretation.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/AnyPartialInterpretation.java
index ebe82c8b..000171a1 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/AnyPartialInterpretation.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/AnyPartialInterpretation.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning;
 
 import tools.refinery.store.reasoning.representation.AnyPartialSymbol;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/MergeResult.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/MergeResult.java
index 0d51598b..d3a216d8 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/MergeResult.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/MergeResult.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning;
 
 public enum MergeResult {
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/PartialInterpretation.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/PartialInterpretation.java
index 4f195e97..4140d640 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/PartialInterpretation.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/PartialInterpretation.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning;
 
 import tools.refinery.store.reasoning.representation.PartialSymbol;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/Reasoning.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/Reasoning.java
deleted file mode 100644
index d7d0a999..00000000
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/Reasoning.java
+++ /dev/null
@@ -1,24 +0,0 @@
-package tools.refinery.store.reasoning;
-
-import tools.refinery.store.reasoning.internal.ReasoningBuilderImpl;
-import tools.refinery.store.adapter.ModelAdapterBuilderFactory;
-import tools.refinery.store.model.ModelStoreBuilder;
-import tools.refinery.store.reasoning.representation.PartialRelation;
-
-public final class Reasoning extends ModelAdapterBuilderFactory<ReasoningAdapter,
-                ReasoningStoreAdapter, ReasoningBuilder> {
-        public static final Reasoning ADAPTER = new Reasoning();
-
-        public static final PartialRelation EXISTS = new PartialRelation("exists", 1);
-
-        public static final PartialRelation EQUALS = new PartialRelation("equals", 1);
-
-        private Reasoning() {
-                super(ReasoningAdapter.class, ReasoningStoreAdapter.class, ReasoningBuilder.class);
-        }
-
-        @Override
-        public ReasoningBuilder createBuilder(ModelStoreBuilder storeBuilder) {
-                return new ReasoningBuilderImpl(storeBuilder);
-        }
-}
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/ReasoningAdapter.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/ReasoningAdapter.java
index de039dd9..8f319242 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/ReasoningAdapter.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/ReasoningAdapter.java
@@ -1,12 +1,20 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning;
 
 import tools.refinery.store.adapter.ModelAdapter;
+import tools.refinery.store.query.ResultSet;
+import tools.refinery.store.query.dnf.Dnf;
 import tools.refinery.store.reasoning.representation.AnyPartialSymbol;
+import tools.refinery.store.reasoning.representation.PartialRelation;
 import tools.refinery.store.reasoning.representation.PartialSymbol;
-import tools.refinery.store.query.dnf.Dnf;
-import tools.refinery.store.query.ResultSet;
 
 public interface ReasoningAdapter extends ModelAdapter {
+        PartialRelation EXISTS = new PartialRelation("exists", 1);
+
         @Override
         ReasoningStoreAdapter getStoreAdapter();
 
@@ -18,5 +26,5 @@ public interface ReasoningAdapter extends ModelAdapter {
 
         <A, C> PartialInterpretation<A, C> getPartialInterpretation(PartialSymbol<A, C> partialSymbol);
 
-        ResultSet getLiftedResultSet(Dnf query);
+        ResultSet<Boolean> getLiftedResultSet(Dnf query);
 }
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/ReasoningBuilder.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/ReasoningBuilder.java
index 4030d296..d3a337e8 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/ReasoningBuilder.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/ReasoningBuilder.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning;
 
 import tools.refinery.store.adapter.ModelAdapterBuilder;
@@ -24,5 +29,5 @@ public interface ReasoningBuilder extends ModelAdapterBuilder {
         Dnf lift(Modality modality, Dnf query);
 
         @Override
-        ReasoningStoreAdapter createStoreAdapter(ModelStore store);
+        ReasoningStoreAdapter build(ModelStore store);
 }
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/ReasoningStoreAdapter.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/ReasoningStoreAdapter.java
index f6a6e414..c9795255 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/ReasoningStoreAdapter.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/ReasoningStoreAdapter.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning;
 
 import tools.refinery.store.adapter.ModelStoreAdapter;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/internal/ReasoningAdapterImpl.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/internal/ReasoningAdapterImpl.java
index 0acf0d49..33b6f3c6 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/internal/ReasoningAdapterImpl.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/internal/ReasoningAdapterImpl.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.internal;
 
 import tools.refinery.store.model.Model;
@@ -32,7 +37,7 @@ public class ReasoningAdapterImpl implements ReasoningAdapter {
         }
 
         @Override
-        public ResultSet getLiftedResultSet(Dnf query) {
+        public ResultSet<Boolean> getLiftedResultSet(Dnf query) {
                 return null;
         }
 }
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/internal/ReasoningBuilderImpl.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/internal/ReasoningBuilderImpl.java
index e11b14bf..aa71496c 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/internal/ReasoningBuilderImpl.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/internal/ReasoningBuilderImpl.java
@@ -1,17 +1,18 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.internal;
 
 import tools.refinery.store.adapter.AbstractModelAdapterBuilder;
 import tools.refinery.store.model.ModelStore;
-import tools.refinery.store.model.ModelStoreBuilder;
+import tools.refinery.store.query.dnf.Dnf;
 import tools.refinery.store.reasoning.ReasoningBuilder;
 import tools.refinery.store.reasoning.literal.Modality;
-import tools.refinery.store.query.dnf.Dnf;
-
-public class ReasoningBuilderImpl extends AbstractModelAdapterBuilder implements ReasoningBuilder {
-        public ReasoningBuilderImpl(ModelStoreBuilder storeBuilder) {
-                super(storeBuilder);
-        }
 
+public class ReasoningBuilderImpl extends AbstractModelAdapterBuilder<ReasoningStoreAdapterImpl>
+                implements ReasoningBuilder {
         @Override
         public ReasoningBuilder liftedQuery(Dnf liftedQuery) {
                 return null;
@@ -19,11 +20,12 @@ public class ReasoningBuilderImpl extends AbstractModelAdapterBuilder implements
 
         @Override
         public Dnf lift(Modality modality, Dnf query) {
+                checkNotConfigured();
                 return null;
         }
 
         @Override
-        public ReasoningStoreAdapterImpl createStoreAdapter(ModelStore store) {
+        public ReasoningStoreAdapterImpl doBuild(ModelStore store) {
                 return null;
         }
 }
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/internal/ReasoningStoreAdapterImpl.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/internal/ReasoningStoreAdapterImpl.java
index ac06e68b..cdddd8d6 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/internal/ReasoningStoreAdapterImpl.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/internal/ReasoningStoreAdapterImpl.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.internal;
 
 import tools.refinery.store.reasoning.ReasoningStoreAdapter;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/lifting/DnfLifter.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/lifting/DnfLifter.java
index 2b0e0f08..ac41d170 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/lifting/DnfLifter.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/lifting/DnfLifter.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.lifting;
 
 import org.jetbrains.annotations.Nullable;
@@ -7,16 +12,16 @@ import tools.refinery.store.query.dnf.DnfClause;
 import tools.refinery.store.query.literal.CallLiteral;
 import tools.refinery.store.query.literal.CallPolarity;
 import tools.refinery.store.query.literal.Literal;
-import tools.refinery.store.query.term.DataVariable;
+import tools.refinery.store.query.term.NodeVariable;
 import tools.refinery.store.query.term.Variable;
-import tools.refinery.store.reasoning.Reasoning;
+import tools.refinery.store.reasoning.ReasoningAdapter;
 import tools.refinery.store.reasoning.literal.ModalConstraint;
 import tools.refinery.store.reasoning.literal.Modality;
 import tools.refinery.store.reasoning.literal.PartialLiterals;
 import tools.refinery.store.util.CycleDetectingMapper;
 
 import java.util.ArrayList;
-import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.List;
 
 public class DnfLifter {
@@ -31,10 +36,10 @@ public class DnfLifter {
                 var modality = modalDnf.modality();
                 var dnf = modalDnf.dnf();
                 var builder = Dnf.builder();
-                builder.parameters(dnf.getParameters());
+                builder.symbolicParameters(dnf.getSymbolicParameters());
                 boolean changed = false;
                 for (var clause : dnf.getClauses()) {
-                        if (liftClause(modality, clause, builder)) {
+                        if (liftClause(modality, dnf, clause, builder)) {
                                 changed = true;
                         }
                 }
@@ -44,12 +49,9 @@ public class DnfLifter {
                 return dnf;
         }
 
-        private boolean liftClause(Modality modality, DnfClause clause, DnfBuilder builder) {
+        private boolean liftClause(Modality modality, Dnf originalDnf, DnfClause clause, DnfBuilder builder) {
                 boolean changed = false;
-                var quantifiedVariables = new HashSet<>(clause.boundVariables()
-                                .stream()
-                                .filter(DataVariable.class::isInstance)
-                                .toList());
+                var quantifiedVariables = getQuantifiedDataVariables(originalDnf, clause);
                 var literals = clause.literals();
                 var liftedLiterals = new ArrayList<Literal>(literals.size());
                 for (var literal : literals) {
@@ -69,20 +71,30 @@ public class DnfLifter {
                 }
                 for (var quantifiedVariable : quantifiedVariables) {
                         // Quantify over data variables that are not already quantified with the expected modality.
-                        liftedLiterals.add(new CallLiteral(CallPolarity.POSITIVE, new ModalConstraint(modality, Reasoning.EXISTS),
-                                        List.of(quantifiedVariable)));
+                        liftedLiterals.add(new CallLiteral(CallPolarity.POSITIVE,
+                                        new ModalConstraint(modality, ReasoningAdapter.EXISTS), List.of(quantifiedVariable)));
                 }
                 builder.clause(liftedLiterals);
                 return changed || !quantifiedVariables.isEmpty();
         }
 
+        private static LinkedHashSet<Variable> getQuantifiedDataVariables(Dnf originalDnf, DnfClause clause) {
+                var quantifiedVariables = new LinkedHashSet<>(clause.positiveVariables());
+                for (var symbolicParameter : originalDnf.getSymbolicParameters()) {
+                        // The existence of parameters will be checked outside this DNF.
+                        quantifiedVariables.remove(symbolicParameter.getVariable());
+                }
+                quantifiedVariables.removeIf(variable -> !(variable instanceof NodeVariable));
+                return quantifiedVariables;
+        }
+
         @Nullable
         private Variable isExistsLiteralForVariable(Modality modality, Literal literal) {
                 if (literal instanceof CallLiteral callLiteral &&
                                 callLiteral.getPolarity() == CallPolarity.POSITIVE &&
                                 callLiteral.getTarget() instanceof ModalConstraint modalConstraint &&
                                 modalConstraint.modality() == modality &&
-                                modalConstraint.constraint().equals(Reasoning.EXISTS)) {
+                                modalConstraint.constraint().equals(ReasoningAdapter.EXISTS)) {
                         return callLiteral.getArguments().get(0);
                 }
                 return null;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/lifting/ModalDnf.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/lifting/ModalDnf.java
index ec381bb8..16fb8fbf 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/lifting/ModalDnf.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/lifting/ModalDnf.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.lifting;
 
 import tools.refinery.store.query.dnf.Dnf;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/literal/ModalConstraint.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/literal/ModalConstraint.java
index 2fbb4607..5ad1d5f8 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/literal/ModalConstraint.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/literal/ModalConstraint.java
@@ -1,9 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.literal;
 
 import tools.refinery.store.query.Constraint;
 import tools.refinery.store.query.equality.LiteralEqualityHelper;
-import tools.refinery.store.query.literal.LiteralReduction;
-import tools.refinery.store.query.term.Sort;
+import tools.refinery.store.query.Reduction;
+import tools.refinery.store.query.term.Parameter;
 
 import java.util.List;
 
@@ -16,12 +21,12 @@ public record ModalConstraint(Modality modality, Constraint constraint) implemen
         }
 
         @Override
-        public List<Sort> getSorts() {
-                return constraint.getSorts();
+        public List<Parameter> getParameters() {
+                return constraint.getParameters();
         }
 
         @Override
-        public LiteralReduction getReduction() {
+        public Reduction getReduction() {
                 return constraint.getReduction();
         }
 
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/literal/Modality.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/literal/Modality.java
index f0cb59de..96466d5c 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/literal/Modality.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/literal/Modality.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.literal;
 
 import tools.refinery.store.query.literal.CallPolarity;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/literal/PartialLiterals.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/literal/PartialLiterals.java
index f991f87f..0e46a795 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/literal/PartialLiterals.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/literal/PartialLiterals.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.literal;
 
 import tools.refinery.store.query.literal.CallLiteral;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/AnyPartialFunction.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/AnyPartialFunction.java
index e74cd58b..8d2cb5cf 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/AnyPartialFunction.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/AnyPartialFunction.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.representation;
 
 public sealed interface AnyPartialFunction extends AnyPartialSymbol permits PartialFunction {
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/AnyPartialSymbol.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/AnyPartialSymbol.java
index 6ff5031b..788eef73 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/AnyPartialSymbol.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/AnyPartialSymbol.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.representation;
 
 import tools.refinery.store.representation.AnyAbstractDomain;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/PartialFunction.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/PartialFunction.java
index 59eeeefe..d58d026f 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/PartialFunction.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/PartialFunction.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.representation;
 
 import tools.refinery.store.representation.AbstractDomain;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/PartialRelation.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/PartialRelation.java
index 9bae53a9..6b2f050b 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/PartialRelation.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/PartialRelation.java
@@ -1,8 +1,12 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.representation;
 
 import tools.refinery.store.query.Constraint;
-import tools.refinery.store.query.term.NodeSort;
-import tools.refinery.store.query.term.Sort;
+import tools.refinery.store.query.term.Parameter;
 import tools.refinery.store.representation.AbstractDomain;
 import tools.refinery.store.representation.TruthValue;
 import tools.refinery.store.representation.TruthValueDomain;
@@ -27,10 +31,10 @@ public record PartialRelation(String name, int arity) implements PartialSymbol<T
         }
 
         @Override
-        public List<Sort> getSorts() {
-                var sorts = new Sort[arity()];
-                Arrays.fill(sorts, NodeSort.INSTANCE);
-                return List.of(sorts);
+        public List<Parameter> getParameters() {
+                var parameters = new Parameter[arity];
+                Arrays.fill(parameters, Parameter.NODE_OUT);
+                return List.of(parameters);
         }
 
         @Override
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/PartialSymbol.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/PartialSymbol.java
index 1af11f2e..3a08bdd8 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/PartialSymbol.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/representation/PartialSymbol.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.representation;
 
 import tools.refinery.store.representation.AbstractDomain;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RelationRefinementAction.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RelationRefinementAction.java
index e8ed05a3..0beee248 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RelationRefinementAction.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RelationRefinementAction.java
@@ -1,6 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.rule;
 
-import tools.refinery.store.reasoning.Reasoning;
+import tools.refinery.store.reasoning.ReasoningAdapter;
 import tools.refinery.store.reasoning.representation.PartialRelation;
 import tools.refinery.store.model.Model;
 import tools.refinery.store.query.term.Variable;
@@ -23,7 +28,7 @@ public record RelationRefinementAction(PartialRelation target, List<Variable> ar
 
         @Override
         public RuleActionExecutor createExecutor(int[] argumentIndices, Model model) {
-                var targetInterpretation = model.getAdapter(Reasoning.ADAPTER).getPartialInterpretation(target);
+                var targetInterpretation = model.getAdapter(ReasoningAdapter.class).getPartialInterpretation(target);
                 return activationTuple -> {
                         int arity = argumentIndices.length;
                         var arguments = new int[arity];
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/Rule.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/Rule.java
index c7b16d47..45b0f02e 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/Rule.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/Rule.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.rule;
 
 import tools.refinery.store.model.Model;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RuleAction.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RuleAction.java
index 4753b8bc..97ea7313 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RuleAction.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RuleAction.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.rule;
 
 import tools.refinery.store.model.Model;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RuleActionExecutor.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RuleActionExecutor.java
index 80bfa6f8..5d743869 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RuleActionExecutor.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RuleActionExecutor.java
@@ -1,9 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.rule;
 
 import tools.refinery.store.reasoning.MergeResult;
-import tools.refinery.store.tuple.TupleLike;
+import tools.refinery.store.tuple.Tuple;
 
 @FunctionalInterface
 public interface RuleActionExecutor {
-        MergeResult execute(TupleLike activationTuple);
+        MergeResult execute(Tuple activationTuple);
 }
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RuleExecutor.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RuleExecutor.java
index 1e5322b4..32cf13ea 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RuleExecutor.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/rule/RuleExecutor.java
@@ -1,8 +1,13 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.rule;
 
-import tools.refinery.store.reasoning.MergeResult;
 import tools.refinery.store.model.Model;
-import tools.refinery.store.tuple.TupleLike;
+import tools.refinery.store.reasoning.MergeResult;
+import tools.refinery.store.tuple.Tuple;
 
 import java.util.List;
 
@@ -24,7 +29,8 @@ public final class RuleExecutor {
         public Model getModel() {
                 return model;
         }
-        public MergeResult execute(TupleLike activationTuple) {
+
+        public MergeResult execute(Tuple activationTuple) {
                 MergeResult mergeResult = MergeResult.UNCHANGED;
                 for (var actionExecutor : actionExecutors) {
                         mergeResult = mergeResult.andAlso(actionExecutor.execute(activationTuple));
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/seed/Seed.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/seed/Seed.java
index 90633495..08079f12 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/seed/Seed.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/seed/Seed.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.seed;
 
 import tools.refinery.store.map.Cursor;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/seed/UniformSeed.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/seed/UniformSeed.java
index a030f6ea..451d1513 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/seed/UniformSeed.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/seed/UniformSeed.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.seed;
 
 import tools.refinery.store.map.Cursor;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/Advice.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/Advice.java
index 5cdfedf7..d6a9e02c 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/Advice.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/Advice.java
@@ -1,10 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator;
 
+import tools.refinery.store.query.substitution.Substitution;
 import tools.refinery.store.reasoning.representation.AnyPartialSymbol;
 import tools.refinery.store.reasoning.representation.PartialRelation;
 import tools.refinery.store.query.term.Variable;
 import tools.refinery.store.query.literal.Literal;
-import tools.refinery.store.query.substitution.Substitutions;
 
 import java.util.*;
 
@@ -61,14 +66,9 @@ public final class Advice {
         public List<Literal> substitute(List<Variable> substituteParameters) {
                 checkArity(substituteParameters);
                 markProcessed();
-                int arity = parameters.size();
-                var variableMap = new HashMap<Variable, Variable>(arity);
-                for (int i = 0; i < arity; i++) {
-                        variableMap.put(parameters.get(i), substituteParameters.get(i));
-                }
                 // Use a renewing substitution to remove any non-parameter variables and avoid clashed between variables
                 // coming from different advice in the same clause.
-                var substitution = Substitutions.renewing(variableMap);
+                var substitution = Substitution.builder().putManyChecked(parameters, substituteParameters).renewing().build();
                 return literals.stream().map(literal -> literal.substitute(substitution)).toList();
         }
 
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/AdviceSlot.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/AdviceSlot.java
index f3bd9c5e..bab20340 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/AdviceSlot.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/AdviceSlot.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator;
 
 import tools.refinery.store.representation.TruthValue;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/TranslatedRelation.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/TranslatedRelation.java
index 9bab80c9..4a5a8843 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/TranslatedRelation.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/TranslatedRelation.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator;
 
 import tools.refinery.store.model.Model;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/TranslationUnit.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/TranslationUnit.java
index 24b93911..6e44a7d7 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/TranslationUnit.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/TranslationUnit.java
@@ -1,7 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator;
 
 import tools.refinery.store.model.Model;
-import tools.refinery.store.model.ModelStoreBuilder;
 import tools.refinery.store.reasoning.ReasoningBuilder;
 
 import java.util.Collection;
@@ -18,10 +22,6 @@ public abstract class TranslationUnit {
                 configureReasoningBuilder();
         }
 
-        protected ModelStoreBuilder getModelStoreBuilder() {
-                return reasoningBuilder.getStoreBuilder();
-        }
-
         protected void configureReasoningBuilder() {
                 // Nothing to configure by default.
         }
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/base/BaseDecisionInterpretation.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/base/BaseDecisionInterpretation.java
index b703f142..e7b67ae4 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/base/BaseDecisionInterpretation.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/base/BaseDecisionInterpretation.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.base;
 
 import tools.refinery.store.map.Cursor;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/base/BaseDecisionTranslationUnit.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/base/BaseDecisionTranslationUnit.java
index 36e2782a..a1e4b816 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/base/BaseDecisionTranslationUnit.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/base/BaseDecisionTranslationUnit.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.base;
 
 import tools.refinery.store.model.Model;
@@ -24,7 +29,7 @@ public class BaseDecisionTranslationUnit extends TranslationUnit {
                 }
                 this.partialRelation = partialRelation;
                 this.seed = seed;
-                symbol = new Symbol<>(partialRelation.name(), partialRelation.arity(), TruthValue.class, TruthValue.UNKNOWN);
+                symbol = Symbol.of(partialRelation.name(), partialRelation.arity(), TruthValue.class, TruthValue.UNKNOWN);
         }
 
         public BaseDecisionTranslationUnit(PartialRelation partialRelation) {
@@ -32,11 +37,6 @@ public class BaseDecisionTranslationUnit extends TranslationUnit {
         }
 
         @Override
-        protected void configureReasoningBuilder() {
-                getModelStoreBuilder().symbol(symbol);
-        }
-
-        @Override
         public Collection<TranslatedRelation> getTranslatedRelations() {
                 return List.of(new TranslatedBaseDecision(getReasoningBuilder(), partialRelation, symbol));
         }
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/base/TranslatedBaseDecision.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/base/TranslatedBaseDecision.java
index 2294b4fd..4782eb46 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/base/TranslatedBaseDecision.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/base/TranslatedBaseDecision.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.base;
 
 import tools.refinery.store.model.Model;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/EliminatedType.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/EliminatedType.java
index 1b8d7cc9..6e4728db 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/EliminatedType.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/EliminatedType.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import tools.refinery.store.reasoning.representation.PartialRelation;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/ExtendedTypeInfo.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/ExtendedTypeInfo.java
index 43b8e1dd..7a917dcf 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/ExtendedTypeInfo.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/ExtendedTypeInfo.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import org.jetbrains.annotations.NotNull;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredMayTypeRelationView.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredMayTypeView.java
index 12c37c86..ce2d6ff3 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredMayTypeRelationView.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredMayTypeView.java
@@ -1,13 +1,18 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import tools.refinery.store.reasoning.representation.PartialRelation;
-import tools.refinery.store.query.view.TuplePreservingRelationView;
+import tools.refinery.store.query.view.TuplePreservingView;
 import tools.refinery.store.tuple.Tuple;
 
-class InferredMayTypeRelationView extends TuplePreservingRelationView<InferredType> {
+class InferredMayTypeView extends TuplePreservingView<InferredType> {
         private final PartialRelation type;
 
-        InferredMayTypeRelationView(PartialRelation type) {
+        InferredMayTypeView(PartialRelation type) {
                 super(TypeHierarchyTranslationUnit.INFERRED_TYPE_SYMBOL, "%s#may".formatted(type));
                 this.type = type;
         }
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredMustTypeRelationView.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredMustTypeView.java
index 975f627e..beda1796 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredMustTypeRelationView.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredMustTypeView.java
@@ -1,13 +1,18 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import tools.refinery.store.reasoning.representation.PartialRelation;
-import tools.refinery.store.query.view.TuplePreservingRelationView;
+import tools.refinery.store.query.view.TuplePreservingView;
 import tools.refinery.store.tuple.Tuple;
 
-class InferredMustTypeRelationView extends TuplePreservingRelationView<InferredType> {
+class InferredMustTypeView extends TuplePreservingView<InferredType> {
         private final PartialRelation type;
 
-        InferredMustTypeRelationView(PartialRelation type) {
+        InferredMustTypeView(PartialRelation type) {
                 super(TypeHierarchyTranslationUnit.INFERRED_TYPE_SYMBOL, "%s#must".formatted(type));
                 this.type = type;
         }
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredType.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredType.java
index a366e262..fd05158b 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredType.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredType.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import tools.refinery.store.reasoning.representation.PartialRelation;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/PreservedType.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/PreservedType.java
index 63dba964..0696f4c3 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/PreservedType.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/PreservedType.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import tools.refinery.store.reasoning.representation.PartialRelation;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalysisResult.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalysisResult.java
index 4f915108..fbf8a7c9 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalysisResult.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalysisResult.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 sealed interface TypeAnalysisResult permits EliminatedType, PreservedType {
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzer.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzer.java
index 62f8e750..e97ce954 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzer.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzer.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import tools.refinery.store.reasoning.representation.PartialRelation;
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeHierarchyTranslationUnit.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeHierarchyTranslationUnit.java
index 4b0761f2..06e3c05f 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeHierarchyTranslationUnit.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeHierarchyTranslationUnit.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import tools.refinery.store.model.Model;
@@ -11,8 +16,8 @@ import java.util.List;
 import java.util.Map;
 
 public class TypeHierarchyTranslationUnit extends TranslationUnit {
-        static final Symbol<InferredType> INFERRED_TYPE_SYMBOL = new Symbol<>("inferredType", 1,
-                        InferredType.class, InferredType.UNTYPED);
+        static final Symbol<InferredType> INFERRED_TYPE_SYMBOL = Symbol.of(
+                        "inferredType", 1, InferredType.class, InferredType.UNTYPED);
 
         private final TypeAnalyzer typeAnalyzer;
 
diff --git a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeInfo.java b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeInfo.java
index 313df4df..9f897e46 100644
--- a/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeInfo.java
+++ b/subprojects/store-reasoning/src/main/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeInfo.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import tools.refinery.store.reasoning.representation.PartialRelation;
diff --git a/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredTypeTest.java b/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredTypeTest.java
index a8df2312..1d76855c 100644
--- a/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredTypeTest.java
+++ b/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/InferredTypeTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import org.junit.jupiter.api.Test;
diff --git a/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzerExampleHierarchyTest.java b/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzerExampleHierarchyTest.java
index b2c1ef1b..05a476c6 100644
--- a/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzerExampleHierarchyTest.java
+++ b/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzerExampleHierarchyTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import org.junit.jupiter.api.BeforeEach;
diff --git a/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzerTest.java b/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzerTest.java
index b7b69ed8..d0ef9d57 100644
--- a/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzerTest.java
+++ b/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzerTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import org.junit.jupiter.api.Test;
diff --git a/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzerTester.java b/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzerTester.java
index 56407730..2924816e 100644
--- a/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzerTester.java
+++ b/subprojects/store-reasoning/src/test/java/tools/refinery/store/reasoning/translator/typehierarchy/TypeAnalyzerTester.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.reasoning.translator.typehierarchy;
 
 import tools.refinery.store.reasoning.representation.PartialRelation;
diff --git a/subprojects/store/build.gradle b/subprojects/store/build.gradle
deleted file mode 100644
index 370d094b..00000000
--- a/subprojects/store/build.gradle
+++ /dev/null
@@ -1,4 +0,0 @@
-plugins {
-        id 'refinery-java-library'
-        id 'refinery-jmh'
-}
diff --git a/subprojects/store/build.gradle.kts b/subprojects/store/build.gradle.kts
new file mode 100644
index 00000000..2c485020
--- /dev/null
+++ b/subprojects/store/build.gradle.kts
@@ -0,0 +1,10 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+
+plugins {
+        id("tools.refinery.gradle.java-library")
+        id("tools.refinery.gradle.jmh")
+}
diff --git a/subprojects/store/src/jmh/java/tools/refinery/store/map/benchmarks/ImmutablePutBenchmark.java b/subprojects/store/src/jmh/java/tools/refinery/store/map/benchmarks/ImmutablePutBenchmark.java
index cdf3d3c8..485fda3d 100644
--- a/subprojects/store/src/jmh/java/tools/refinery/store/map/benchmarks/ImmutablePutBenchmark.java
+++ b/subprojects/store/src/jmh/java/tools/refinery/store/map/benchmarks/ImmutablePutBenchmark.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.benchmarks;
 
 import java.util.ArrayList;
diff --git a/subprojects/store/src/jmh/java/tools/refinery/store/map/benchmarks/ImmutablePutExecutionPlan.java b/subprojects/store/src/jmh/java/tools/refinery/store/map/benchmarks/ImmutablePutExecutionPlan.java
index 756d504e..edd4f53e 100644
--- a/subprojects/store/src/jmh/java/tools/refinery/store/map/benchmarks/ImmutablePutExecutionPlan.java
+++ b/subprojects/store/src/jmh/java/tools/refinery/store/map/benchmarks/ImmutablePutExecutionPlan.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.benchmarks;
 
 import java.util.Random;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/adapter/AbstractModelAdapterBuilder.java b/subprojects/store/src/main/java/tools/refinery/store/adapter/AbstractModelAdapterBuilder.java
index 4c142217..8d3e998e 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/adapter/AbstractModelAdapterBuilder.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/adapter/AbstractModelAdapterBuilder.java
@@ -1,27 +1,48 @@
 package tools.refinery.store.adapter;
-
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 import tools.refinery.store.model.ModelStore;
 import tools.refinery.store.model.ModelStoreBuilder;
 
-public abstract class AbstractModelAdapterBuilder implements ModelAdapterBuilder {
-        private final ModelStoreBuilder storeBuilder;
+public abstract class AbstractModelAdapterBuilder<T extends ModelStoreAdapter> implements ModelAdapterBuilder {
+        private boolean configured;
 
-        protected AbstractModelAdapterBuilder(ModelStoreBuilder storeBuilder) {
-                this.storeBuilder = storeBuilder;
+        @Override
+        public boolean isConfigured() {
+                return configured;
         }
 
-        @Override
-        public <T extends ModelAdapterBuilder> T with(ModelAdapterBuilderFactory<?, ?, T> adapterBuilderFactory) {
-                return storeBuilder.with(adapterBuilderFactory);
+        protected void checkConfigured() {
+                if (!configured) {
+                        throw new IllegalStateException("Model adapter builder was not configured");
+                }
+        }
+
+        protected void checkNotConfigured() {
+                if (configured) {
+                        throw new IllegalStateException("Model adapter builder was already configured");
+                }
+        }
+
+        protected void doConfigure(ModelStoreBuilder storeBuilder) {
+                // Nothing to configure by default.
         }
 
         @Override
-        public ModelStoreBuilder getStoreBuilder() {
-                return storeBuilder;
+        public final void configure(ModelStoreBuilder storeBuilder) {
+                checkNotConfigured();
+                doConfigure(storeBuilder);
+                configured = true;
         }
 
+        protected abstract T doBuild(ModelStore store);
+
         @Override
-        public ModelStore build() {
-                return storeBuilder.build();
+        public final T build(ModelStore store) {
+                checkConfigured();
+                return doBuild(store);
         }
 }
diff --git a/subprojects/store/src/main/java/tools/refinery/store/adapter/AdapterList.java b/subprojects/store/src/main/java/tools/refinery/store/adapter/AdapterList.java
deleted file mode 100644
index 74bae6f0..00000000
--- a/subprojects/store/src/main/java/tools/refinery/store/adapter/AdapterList.java
+++ /dev/null
@@ -1,97 +0,0 @@
-package tools.refinery.store.adapter;
-
-import org.jetbrains.annotations.NotNull;
-
-import java.util.*;
-import java.util.function.Consumer;
-
-public class AdapterList<T> implements Iterable<T> {
-        private final List<AnyModelAdapterType> adapterTypes;
-        private final List<T> adapters;
-
-        public AdapterList() {
-                adapterTypes = new ArrayList<>();
-                adapters = new ArrayList<>();
-        }
-
-        public AdapterList(int adapterCount) {
-                adapterTypes = new ArrayList<>(adapterCount);
-                adapters = new ArrayList<>(adapterCount);
-        }
-
-        public int size() {
-                return adapters.size();
-        }
-
-        public void add(AnyModelAdapterType adapterType, T adapter) {
-                adapterTypes.add(adapterType);
-                adapters.add(adapter);
-        }
-
-        public <U extends T> Optional<U> tryGet(AnyModelAdapterType adapterType, Class<? extends U> adapterClass) {
-                int size = size();
-                for (int i = 0; i < size; i++) {
-                        if (getType(i).supports(adapterType)) {
-                                return Optional.of(adapterClass.cast(get(i)));
-                        }
-                }
-                return Optional.empty();
-        }
-
-        public <U extends T> U get(AnyModelAdapterType adapterType, Class<U> adapterClass) {
-                return tryGet(adapterType, adapterClass).orElseThrow(() -> new IllegalArgumentException(
-                                "No %s was configured".formatted(adapterType)));
-        }
-
-        public AnyModelAdapterType getType(int i) {
-                return adapterTypes.get(i);
-        }
-
-        public T get(int i) {
-                return adapters.get(i);
-        }
-
-        public Collection<AnyModelAdapterType> getAdapterTypes() {
-                return Collections.unmodifiableCollection(adapterTypes);
-        }
-
-        public Iterable<Entry<T>> withAdapterTypes() {
-                return () -> new Iterator<>() {
-                        private int i = 0;
-
-                        @Override
-                        public boolean hasNext() {
-                                return i < size();
-                        }
-
-                        @Override
-                        public Entry<T> next() {
-                                if (i >= size()) {
-                                        throw new NoSuchElementException();
-                                }
-                                var entry = new Entry<>(getType(i), get(i));
-                                i++;
-                                return entry;
-                        }
-                };
-        }
-
-        @NotNull
-        @Override
-        public Iterator<T> iterator() {
-                return adapters.iterator();
-        }
-
-        @Override
-        public void forEach(Consumer<? super T> action) {
-                adapters.forEach(action);
-        }
-
-        @Override
-        public Spliterator<T> spliterator() {
-                return adapters.spliterator();
-        }
-
-        public record Entry<T>(AnyModelAdapterType adapterType, T adapter) {
-        }
-}
diff --git a/subprojects/store/src/main/java/tools/refinery/store/adapter/AdapterUtils.java b/subprojects/store/src/main/java/tools/refinery/store/adapter/AdapterUtils.java
new file mode 100644
index 00000000..556e99f0
--- /dev/null
+++ b/subprojects/store/src/main/java/tools/refinery/store/adapter/AdapterUtils.java
@@ -0,0 +1,33 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.adapter;
+
+import java.util.Collection;
+import java.util.Optional;
+
+public class AdapterUtils {
+        private AdapterUtils() {
+                throw new IllegalStateException("This is a static utility class and should not be instantiated directly");
+        }
+
+        public static <T, U extends T> Optional<U> tryGetAdapter(Collection<T> adapters, Class<? extends U> type) {
+                var iterator = adapters.stream().filter(type::isInstance).iterator();
+                if (!iterator.hasNext()) {
+                        return Optional.empty();
+                }
+                var adapter = type.cast(iterator.next());
+                if (iterator.hasNext()) {
+                        throw new IllegalArgumentException("Ambiguous adapter: both %s and %s match %s"
+                                        .formatted(adapter.getClass().getName(), iterator.next().getClass().getName(), type.getName()));
+                }
+                return Optional.of(adapter);
+        }
+
+        public static <T> T getAdapter(Collection<? super T> adapters, Class<T> type) {
+                return tryGetAdapter(adapters, type).orElseThrow(() -> new IllegalArgumentException(
+                                "No %s adapter was configured".formatted(type.getName())));
+        }
+}
diff --git a/subprojects/store/src/main/java/tools/refinery/store/adapter/AnyModelAdapterType.java b/subprojects/store/src/main/java/tools/refinery/store/adapter/AnyModelAdapterType.java
deleted file mode 100644
index 37a247fe..00000000
--- a/subprojects/store/src/main/java/tools/refinery/store/adapter/AnyModelAdapterType.java
+++ /dev/null
@@ -1,19 +0,0 @@
-package tools.refinery.store.adapter;
-
-import java.util.Collection;
-
-public sealed interface AnyModelAdapterType permits ModelAdapterType {
-        Class<? extends ModelAdapter> getModelAdapterClass();
-
-        Class<? extends ModelStoreAdapter> getModelStoreAdapterClass();
-
-        Class<? extends ModelAdapterBuilder> getModelAdapterBuilderClass();
-
-        Collection<AnyModelAdapterType> getSupportedAdapterTypes();
-
-        default boolean supports(AnyModelAdapterType targetAdapter) {
-                return getSupportedAdapterTypes().contains(targetAdapter);
-        }
-
-        String getName();
-}
diff --git a/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapter.java b/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapter.java
index aa079e01..672007aa 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapter.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapter.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.adapter;
 
 import tools.refinery.store.model.Model;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapterBuilder.java b/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapterBuilder.java
index 64b3e59f..75e5e07d 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapterBuilder.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapterBuilder.java
@@ -1,17 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.adapter;
 
 import tools.refinery.store.model.ModelStore;
 import tools.refinery.store.model.ModelStoreBuilder;
 
 public interface ModelAdapterBuilder {
-        ModelStoreAdapter createStoreAdapter(ModelStore store);
+        boolean isConfigured();
 
-        <T extends ModelAdapterBuilder> T with(ModelAdapterBuilderFactory<?, ?, T> adapterBuilderFactory);
+        void configure(ModelStoreBuilder storeBuilder);
 
-        ModelStoreBuilder getStoreBuilder();
-
-        default void configure() {
-        }
-
-        ModelStore build();
+        ModelStoreAdapter build(ModelStore store);
 }
diff --git a/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapterBuilderFactory.java b/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapterBuilderFactory.java
deleted file mode 100644
index 7c9b01bc..00000000
--- a/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapterBuilderFactory.java
+++ /dev/null
@@ -1,14 +0,0 @@
-package tools.refinery.store.adapter;
-
-import tools.refinery.store.model.ModelStoreBuilder;
-
-public abstract class ModelAdapterBuilderFactory<T1 extends ModelAdapter, T2 extends ModelStoreAdapter,
-                T3 extends ModelAdapterBuilder> extends ModelAdapterType<T1, T2, T3> {
-
-        protected ModelAdapterBuilderFactory(Class<T1> modelAdapterClass, Class<T2> modelStoreAdapterClass,
-                                                                                 Class<T3> modelAdapterBuilderClass) {
-                super(modelAdapterClass, modelStoreAdapterClass, modelAdapterBuilderClass);
-        }
-
-        public abstract T3 createBuilder(ModelStoreBuilder storeBuilder);
-}
diff --git a/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapterType.java b/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapterType.java
deleted file mode 100644
index 82ddeb12..00000000
--- a/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelAdapterType.java
+++ /dev/null
@@ -1,79 +0,0 @@
-package tools.refinery.store.adapter;
-
-import tools.refinery.store.model.Model;
-import tools.refinery.store.model.ModelStore;
-
-import java.lang.reflect.Method;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.HashSet;
-import java.util.Set;
-
-public abstract non-sealed class ModelAdapterType<T1 extends ModelAdapter, T2 extends ModelStoreAdapter,
-                T3 extends ModelAdapterBuilder> implements AnyModelAdapterType {
-        private final Class<? extends T1> modelAdapterClass;
-        private final Class<? extends T2> modelStoreAdapterClass;
-        private final Class<? extends T3> modelAdapterBuilderClass;
-        private final Set<AnyModelAdapterType> supportedAdapters = new HashSet<>();
-
-        protected ModelAdapterType(Class<T1> modelAdapterClass, Class<T2> modelStoreAdapterClass,
-                                                           Class<T3> modelAdapterBuilderClass) {
-                checkReturnType(modelAdapterClass, modelStoreAdapterClass, "createModelAdapter", Model.class);
-                checkReturnType(modelStoreAdapterClass, modelAdapterBuilderClass, "createStoreAdapter", ModelStore.class);
-                this.modelAdapterClass = modelAdapterClass;
-                this.modelStoreAdapterClass = modelStoreAdapterClass;
-                this.modelAdapterBuilderClass = modelAdapterBuilderClass;
-                supportedAdapters.add(this);
-        }
-
-        private void checkReturnType(Class<?> expectedReturnType, Class<?> ownerClass, String methodName,
-                                                                 Class<?>... argumentTypes) {
-                Method method;
-                try {
-                        method = ownerClass.getMethod(methodName, argumentTypes);
-                } catch (NoSuchMethodException e) {
-                        throw new IllegalStateException("Invalid %s: %s#%s method is required"
-                                        .formatted(this, ownerClass.getName(), methodName), e);
-                }
-                var returnType = method.getReturnType();
-                if (!expectedReturnType.isAssignableFrom(returnType)) {
-                        throw new IllegalStateException("Invalid %s: %s is not assignable from the return type %s of %s#%s"
-                                        .formatted(this, expectedReturnType.getName(), returnType.getCanonicalName(),
-                                                        ownerClass.getName(), methodName));
-                }
-        }
-
-        protected void extendsAdapter(ModelAdapterType<? super T1, ? super T2, ? super T3> superAdapter) {
-                supportedAdapters.addAll(superAdapter.supportedAdapters);
-        }
-
-        @Override
-        public final Class<? extends T1> getModelAdapterClass() {
-                return modelAdapterClass;
-        }
-
-        @Override
-        public final Class<? extends T2> getModelStoreAdapterClass() {
-                return modelStoreAdapterClass;
-        }
-
-        @Override
-        public final Class<? extends T3> getModelAdapterBuilderClass() {
-                return modelAdapterBuilderClass;
-        }
-
-        @Override
-        public Collection<AnyModelAdapterType> getSupportedAdapterTypes() {
-                return Collections.unmodifiableCollection(supportedAdapters);
-        }
-
-        @Override
-        public String getName() {
-                return "%s.ADAPTER".formatted(this.getClass().getName());
-        }
-
-        @Override
-        public String toString() {
-                return getName();
-        }
-}
diff --git a/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelStoreAdapter.java b/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelStoreAdapter.java
index 1eb40ada..bc5f7b6b 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelStoreAdapter.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/adapter/ModelStoreAdapter.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.adapter;
 
 import tools.refinery.store.model.Model;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/AnyVersionedMap.java b/subprojects/store/src/main/java/tools/refinery/store/map/AnyVersionedMap.java
index f82a8bb1..25fc91e6 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/AnyVersionedMap.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/AnyVersionedMap.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 public sealed interface AnyVersionedMap extends Versioned permits VersionedMap {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/ContentHashCode.java b/subprojects/store/src/main/java/tools/refinery/store/map/ContentHashCode.java
index 8deeab23..cbea05e1 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/ContentHashCode.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/ContentHashCode.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 public enum ContentHashCode {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/ContinousHashProvider.java b/subprojects/store/src/main/java/tools/refinery/store/map/ContinousHashProvider.java
index 75f1e2ab..8e451230 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/ContinousHashProvider.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/ContinousHashProvider.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 import tools.refinery.store.map.internal.Node;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/Cursor.java b/subprojects/store/src/main/java/tools/refinery/store/map/Cursor.java
index b420585c..3bdca104 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/Cursor.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/Cursor.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 import java.util.Set;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/CursorAsIterator.java b/subprojects/store/src/main/java/tools/refinery/store/map/CursorAsIterator.java
index 65ae6648..c7e4d279 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/CursorAsIterator.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/CursorAsIterator.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 import java.util.Iterator;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/Cursors.java b/subprojects/store/src/main/java/tools/refinery/store/map/Cursors.java
index fc8e628b..0a94d449 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/Cursors.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/Cursors.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 public final class Cursors {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/DiffCursor.java b/subprojects/store/src/main/java/tools/refinery/store/map/DiffCursor.java
index 701f3ec8..4322e041 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/DiffCursor.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/DiffCursor.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 public interface DiffCursor<K, V> extends Cursor<K,V> {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/MapAsIterable.java b/subprojects/store/src/main/java/tools/refinery/store/map/MapAsIterable.java
index 6b986732..199b548f 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/MapAsIterable.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/MapAsIterable.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 import java.util.Iterator;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/Versioned.java b/subprojects/store/src/main/java/tools/refinery/store/map/Versioned.java
index 6a23e9d5..55720db3 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/Versioned.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/Versioned.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 public interface Versioned {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMap.java b/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMap.java
index 31985e94..9bbde24d 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMap.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMap.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 public non-sealed interface VersionedMap<K, V> extends AnyVersionedMap {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMapStore.java b/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMapStore.java
index a8d7fb1a..5aafa338 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMapStore.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMapStore.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 import java.util.Set;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMapStoreConfiguration.java b/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMapStoreConfiguration.java
index 3856460d..b00cd961 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMapStoreConfiguration.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMapStoreConfiguration.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 public class VersionedMapStoreConfiguration {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMapStoreImpl.java b/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMapStoreImpl.java
index 113874e7..aade4aeb 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMapStoreImpl.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/VersionedMapStoreImpl.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map;
 
 import tools.refinery.store.map.internal.ImmutableNode;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/internal/HashClash.java b/subprojects/store/src/main/java/tools/refinery/store/map/internal/HashClash.java
index 5402ed4a..61b3d1b8 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/internal/HashClash.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/internal/HashClash.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.internal;
 
 enum HashClash {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/internal/ImmutableNode.java b/subprojects/store/src/main/java/tools/refinery/store/map/internal/ImmutableNode.java
index 9397dede..03dffc15 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/internal/ImmutableNode.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/internal/ImmutableNode.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.internal;
 
 import java.util.Arrays;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/internal/MapCursor.java b/subprojects/store/src/main/java/tools/refinery/store/map/internal/MapCursor.java
index 91a71e3d..f34ec7bb 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/internal/MapCursor.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/internal/MapCursor.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.internal;
 
 import tools.refinery.store.map.AnyVersionedMap;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/internal/MapDiffCursor.java b/subprojects/store/src/main/java/tools/refinery/store/map/internal/MapDiffCursor.java
index 9cd78113..d31f1a05 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/internal/MapDiffCursor.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/internal/MapDiffCursor.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.internal;
 
 import tools.refinery.store.map.AnyVersionedMap;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/internal/MutableNode.java b/subprojects/store/src/main/java/tools/refinery/store/map/internal/MutableNode.java
index 7c3cf7e8..1129ee5a 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/internal/MutableNode.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/internal/MutableNode.java
@@ -1,10 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.internal;
 
+import tools.refinery.store.map.ContinousHashProvider;
+
 import java.util.Arrays;
 import java.util.Map;
 
-import tools.refinery.store.map.ContinousHashProvider;
-
 public class MutableNode<K, V> extends Node<K, V> {
         int cachedHash;
         protected Object[] content;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/internal/Node.java b/subprojects/store/src/main/java/tools/refinery/store/map/internal/Node.java
index 2260cd5b..958d645f 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/internal/Node.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/internal/Node.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.internal;
 
 import java.util.Map;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/internal/OldValueBox.java b/subprojects/store/src/main/java/tools/refinery/store/map/internal/OldValueBox.java
index 5534c703..354af51d 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/internal/OldValueBox.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/internal/OldValueBox.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.internal;
 
 public class OldValueBox<V>{
diff --git a/subprojects/store/src/main/java/tools/refinery/store/map/internal/VersionedMapImpl.java b/subprojects/store/src/main/java/tools/refinery/store/map/internal/VersionedMapImpl.java
index 301bcb95..7abece0d 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/map/internal/VersionedMapImpl.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/map/internal/VersionedMapImpl.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.internal;
 
 import tools.refinery.store.map.*;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/AnyInterpretation.java b/subprojects/store/src/main/java/tools/refinery/store/model/AnyInterpretation.java
index d18ba71d..f906b48a 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/AnyInterpretation.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/AnyInterpretation.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model;
 
 import tools.refinery.store.representation.AnySymbol;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/Interpretation.java b/subprojects/store/src/main/java/tools/refinery/store/model/Interpretation.java
index 55949d0c..26ad9a69 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/Interpretation.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/Interpretation.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model;
 
 import tools.refinery.store.map.Cursor;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/InterpretationListener.java b/subprojects/store/src/main/java/tools/refinery/store/model/InterpretationListener.java
index 73950779..6f7b24c1 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/InterpretationListener.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/InterpretationListener.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model;
 
 import tools.refinery.store.tuple.Tuple;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/Model.java b/subprojects/store/src/main/java/tools/refinery/store/model/Model.java
index 6ca1ac7b..d58d91c3 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/Model.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/Model.java
@@ -1,7 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model;
 
 import tools.refinery.store.adapter.ModelAdapter;
-import tools.refinery.store.adapter.ModelAdapterType;
 import tools.refinery.store.map.Versioned;
 import tools.refinery.store.representation.AnySymbol;
 import tools.refinery.store.representation.Symbol;
@@ -25,9 +29,9 @@ public interface Model extends Versioned {
 
         ModelDiffCursor getDiffCursor(long to);
 
-        <T extends ModelAdapter> Optional<T> tryGetAdapter(ModelAdapterType<? extends T, ?, ?> adapterType);
+        <T extends ModelAdapter> Optional<T> tryGetAdapter(Class<? extends T> adapterType);
 
-        <T extends ModelAdapter> T getAdapter(ModelAdapterType<T, ?, ?> adapterType);
+        <T extends ModelAdapter> T getAdapter(Class<T> adapterType);
 
         void addListener(ModelListener listener);
 
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/ModelDiffCursor.java b/subprojects/store/src/main/java/tools/refinery/store/model/ModelDiffCursor.java
index 97bf2039..7b236891 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/ModelDiffCursor.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/ModelDiffCursor.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model;
 
 import tools.refinery.store.map.DiffCursor;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/ModelListener.java b/subprojects/store/src/main/java/tools/refinery/store/model/ModelListener.java
index f67540bb..a9ad8cfd 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/ModelListener.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/ModelListener.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model;
 
 public interface ModelListener {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/ModelStore.java b/subprojects/store/src/main/java/tools/refinery/store/model/ModelStore.java
index 2e7e62c3..b10eb8a4 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/ModelStore.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/ModelStore.java
@@ -1,6 +1,10 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model;
 
-import tools.refinery.store.adapter.ModelAdapterType;
 import tools.refinery.store.adapter.ModelStoreAdapter;
 import tools.refinery.store.model.internal.ModelStoreBuilderImpl;
 import tools.refinery.store.representation.AnySymbol;
@@ -20,9 +24,9 @@ public interface ModelStore {
 
         ModelDiffCursor getDiffCursor(long from, long to);
 
-        <T extends ModelStoreAdapter> Optional<T> tryGetAdapter(ModelAdapterType<?, ? extends T, ?> adapterType);
+        <T extends ModelStoreAdapter> Optional<T> tryGetAdapter(Class<? extends T> adapterType);
 
-        <T extends ModelStoreAdapter> T getAdapter(ModelAdapterType<?, T, ?> adapterType);
+        <T extends ModelStoreAdapter> T getAdapter(Class<T> adapterType);
 
         static ModelStoreBuilder builder() {
                 return new ModelStoreBuilderImpl();
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/ModelStoreBuilder.java b/subprojects/store/src/main/java/tools/refinery/store/model/ModelStoreBuilder.java
index 289099da..3a4024b5 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/ModelStoreBuilder.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/ModelStoreBuilder.java
@@ -1,8 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model;
 
 import tools.refinery.store.adapter.ModelAdapterBuilder;
-import tools.refinery.store.adapter.ModelAdapterBuilderFactory;
-import tools.refinery.store.adapter.ModelAdapterType;
 import tools.refinery.store.representation.AnySymbol;
 import tools.refinery.store.representation.Symbol;
 
@@ -26,11 +29,11 @@ public interface ModelStoreBuilder {
 
         <T> ModelStoreBuilder symbol(Symbol<T> symbol);
 
-        <T extends ModelAdapterBuilder> T with(ModelAdapterBuilderFactory<?, ?, T> adapterBuilderFactory);
+        <T extends ModelAdapterBuilder> ModelStoreBuilder with(T adapterBuilder);
 
-        <T extends ModelAdapterBuilder> Optional<T> tryGetAdapter(ModelAdapterType<?, ?, ? extends T> adapterType);
+        <T extends ModelAdapterBuilder> Optional<T> tryGetAdapter(Class<? extends T> adapterType);
 
-        <T extends ModelAdapterBuilder> T getAdapter(ModelAdapterType<?, ?, T> adapterType);
+        <T extends ModelAdapterBuilder> T getAdapter(Class<T> adapterType);
 
         ModelStore build();
 }
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/TupleHashProvider.java b/subprojects/store/src/main/java/tools/refinery/store/model/TupleHashProvider.java
index 4bcf9ff4..fe1c2ab5 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/TupleHashProvider.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/TupleHashProvider.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model;
 
 import tools.refinery.store.map.ContinousHashProvider;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/TupleHashProviderBitMagic.java b/subprojects/store/src/main/java/tools/refinery/store/model/TupleHashProviderBitMagic.java
index 33059a1b..14116a90 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/TupleHashProviderBitMagic.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/TupleHashProviderBitMagic.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model;
 
 import tools.refinery.store.map.ContinousHashProvider;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelAction.java b/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelAction.java
index f68859db..dbd95d80 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelAction.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelAction.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model.internal;
 
 public enum ModelAction {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelImpl.java b/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelImpl.java
index 9eb438c4..c5475a1a 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelImpl.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelImpl.java
@@ -1,9 +1,12 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model.internal;
 
-import tools.refinery.store.adapter.AdapterList;
-import tools.refinery.store.adapter.AnyModelAdapterType;
+import tools.refinery.store.adapter.AdapterUtils;
 import tools.refinery.store.adapter.ModelAdapter;
-import tools.refinery.store.adapter.ModelAdapterType;
 import tools.refinery.store.map.DiffCursor;
 import tools.refinery.store.model.*;
 import tools.refinery.store.representation.AnySymbol;
@@ -16,7 +19,7 @@ public class ModelImpl implements Model {
         private final ModelStore store;
         private long state;
         private Map<? extends AnySymbol, ? extends VersionedInterpretation<?>> interpretations;
-        private final AdapterList<ModelAdapter> adapters;
+        private final List<ModelAdapter> adapters;
         private final List<ModelListener> listeners = new ArrayList<>();
         private boolean uncommittedChanges;
         private ModelAction pendingAction = ModelAction.NONE;
@@ -25,7 +28,7 @@ public class ModelImpl implements Model {
         ModelImpl(ModelStore store, long state, int adapterCount) {
                 this.store = store;
                 this.state = state;
-                adapters = new AdapterList<>(adapterCount);
+                adapters = new ArrayList<>(adapterCount);
         }
 
         void setInterpretations(Map<? extends AnySymbol, ? extends VersionedInterpretation<?>> interpretations) {
@@ -162,17 +165,17 @@ public class ModelImpl implements Model {
         }
 
         @Override
-        public <T extends ModelAdapter> Optional<T> tryGetAdapter(ModelAdapterType<? extends T, ?, ?> adapterType) {
-                return adapters.tryGet(adapterType, adapterType.getModelAdapterClass());
+        public <T extends ModelAdapter> Optional<T> tryGetAdapter(Class<? extends T> adapterType) {
+                return AdapterUtils.tryGetAdapter(adapters, adapterType);
         }
 
         @Override
-        public <T extends ModelAdapter> T getAdapter(ModelAdapterType<T, ?, ?> adapterType) {
-                return adapters.get(adapterType, adapterType.getModelAdapterClass());
+        public <T extends ModelAdapter> T getAdapter(Class<T> adapterType) {
+                return AdapterUtils.getAdapter(adapters, adapterType);
         }
 
-        void addAdapter(AnyModelAdapterType adapterType, ModelAdapter adapter) {
-                adapters.add(adapterType, adapter);
+        void addAdapter(ModelAdapter adapter) {
+                adapters.add(adapter);
         }
 
         @Override
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelStoreBuilderImpl.java b/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelStoreBuilderImpl.java
index 79f7195d..aafbe130 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelStoreBuilderImpl.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelStoreBuilderImpl.java
@@ -1,9 +1,12 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model.internal;
 
-import tools.refinery.store.adapter.AdapterList;
+import tools.refinery.store.adapter.AdapterUtils;
 import tools.refinery.store.adapter.ModelAdapterBuilder;
-import tools.refinery.store.adapter.ModelAdapterBuilderFactory;
-import tools.refinery.store.adapter.ModelAdapterType;
 import tools.refinery.store.map.VersionedMapStore;
 import tools.refinery.store.map.VersionedMapStoreImpl;
 import tools.refinery.store.model.ModelStore;
@@ -18,7 +21,7 @@ import java.util.*;
 public class ModelStoreBuilderImpl implements ModelStoreBuilder {
         private final Set<AnySymbol> allSymbols = new HashSet<>();
         private final Map<SymbolEquivalenceClass<?>, List<AnySymbol>> equivalenceClasses = new HashMap<>();
-        private final AdapterList<ModelAdapterBuilder> adapters = new AdapterList<>();
+        private final List<ModelAdapterBuilder> adapters = new ArrayList<>();
 
         @Override
         public <T> ModelStoreBuilder symbol(Symbol<T> symbol) {
@@ -33,46 +36,25 @@ public class ModelStoreBuilderImpl implements ModelStoreBuilder {
         }
 
         @Override
-        public <T extends ModelAdapterBuilder> T with(ModelAdapterBuilderFactory<?, ?, T> adapterBuilderFactory) {
-                return adapters.<T>tryGet(adapterBuilderFactory, adapterBuilderFactory.getModelAdapterBuilderClass())
-                                .orElseGet(() -> addAdapter(adapterBuilderFactory));
-        }
-
-        private <T extends ModelAdapterBuilder> T addAdapter(ModelAdapterBuilderFactory<?, ?, T> adapterBuilderFactory) {
-                for (var configuredAdapterType : adapters.getAdapterTypes()) {
-                        var intersection = new HashSet<>(adapterBuilderFactory.getSupportedAdapterTypes());
-                        intersection.retainAll(configuredAdapterType.getSupportedAdapterTypes());
-                        if (!intersection.isEmpty()) {
-                                if (configuredAdapterType.supports(adapterBuilderFactory)) {
-                                        // Impossible to end up here from <code>#with</code>, because we should have returned
-                                        // the existing adapter there instead of adding a new one.
-                                        throw new IllegalArgumentException(
-                                                        "Cannot add %s, because it is already provided by configured adapter %s"
-                                                                        .formatted(adapterBuilderFactory, configuredAdapterType));
-                                } else if (adapterBuilderFactory.supports(configuredAdapterType)) {
-                                        throw new IllegalArgumentException(
-                                                        "Cannot add %s, because it provides already configured adapter %s"
-                                                                        .formatted(adapterBuilderFactory, configuredAdapterType));
-                                } else {
-                                        throw new IllegalArgumentException(
-                                                        "Cannot add %s, because configured adapter %s already provides %s"
-                                                                        .formatted(adapterBuilderFactory, configuredAdapterType, intersection));
-                                }
+        public <T extends ModelAdapterBuilder> ModelStoreBuilder with(T adapterBuilder) {
+                for (var existingAdapter : adapters) {
+                        if (existingAdapter.getClass().equals(adapterBuilder.getClass())) {
+                                throw new IllegalArgumentException("%s adapter was already configured for store builder"
+                                                .formatted(adapterBuilder.getClass().getName()));
                         }
                 }
-                var newAdapter = adapterBuilderFactory.createBuilder(this);
-                adapters.add(adapterBuilderFactory, newAdapter);
-                return newAdapter;
+                adapters.add(adapterBuilder);
+                return this;
         }
 
         @Override
-        public <T extends ModelAdapterBuilder> Optional<T> tryGetAdapter(ModelAdapterType<?, ?, ? extends T> adapterType) {
-                return adapters.tryGet(adapterType, adapterType.getModelAdapterBuilderClass());
+        public <T extends ModelAdapterBuilder> Optional<T> tryGetAdapter(Class<? extends T> adapterType) {
+                return AdapterUtils.tryGetAdapter(adapters, adapterType);
         }
 
         @Override
-        public <T extends ModelAdapterBuilder> T getAdapter(ModelAdapterType<?, ?, T> adapterType) {
-                return adapters.get(adapterType, adapterType.getModelAdapterBuilderClass());
+        public <T extends ModelAdapterBuilder> T getAdapter(Class<T> adapterType) {
+                return AdapterUtils.getAdapter(adapters, adapterType);
         }
 
         @Override
@@ -81,13 +63,13 @@ public class ModelStoreBuilderImpl implements ModelStoreBuilder {
                 for (var entry : equivalenceClasses.entrySet()) {
                         createStores(stores, entry.getKey(), entry.getValue());
                 }
-                var modelStore = new ModelStoreImpl(stores, adapters.size());
                 for (int i = adapters.size() - 1; i >= 0; i--) {
-                        adapters.get(i).configure();
+                        adapters.get(i).configure(this);
                 }
-                for (var entry : adapters.withAdapterTypes()) {
-                        var adapter = entry.adapter().createStoreAdapter(modelStore);
-                        modelStore.addAdapter(entry.adapterType(), adapter);
+                var modelStore = new ModelStoreImpl(stores, adapters.size());
+                for (var adapterBuilder : adapters) {
+                        var storeAdapter = adapterBuilder.build(modelStore);
+                        modelStore.addAdapter(storeAdapter);
                 }
                 return modelStore;
         }
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelStoreImpl.java b/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelStoreImpl.java
index e8c205e4..60b735e6 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelStoreImpl.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/internal/ModelStoreImpl.java
@@ -1,8 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model.internal;
 
-import tools.refinery.store.adapter.AdapterList;
-import tools.refinery.store.adapter.AnyModelAdapterType;
-import tools.refinery.store.adapter.ModelAdapterType;
+import tools.refinery.store.adapter.AdapterUtils;
 import tools.refinery.store.adapter.ModelStoreAdapter;
 import tools.refinery.store.map.DiffCursor;
 import tools.refinery.store.map.VersionedMapStore;
@@ -16,11 +19,11 @@ import java.util.*;
 
 public class ModelStoreImpl implements ModelStore {
         private final Map<? extends AnySymbol, ? extends VersionedMapStore<Tuple, ?>> stores;
-        private final AdapterList<ModelStoreAdapter> adapters;
+        private final List<ModelStoreAdapter> adapters;
 
         ModelStoreImpl(Map<? extends AnySymbol, ? extends VersionedMapStore<Tuple, ?>> stores, int adapterCount) {
                 this.stores = stores;
-                adapters = new AdapterList<>(adapterCount);
+                adapters = new ArrayList<>(adapterCount);
         }
 
         @Override
@@ -59,9 +62,9 @@ public class ModelStoreImpl implements ModelStore {
         }
 
         private void adaptModel(ModelImpl model) {
-                for (var entry : adapters.withAdapterTypes()) {
-                        var adapter = entry.adapter().createModelAdapter(model);
-                        model.addAdapter(entry.adapterType(), adapter);
+                for (var storeAdapter : adapters) {
+                        var adapter = storeAdapter.createModelAdapter(model);
+                        model.addAdapter(adapter);
                 }
         }
 
@@ -86,16 +89,16 @@ public class ModelStoreImpl implements ModelStore {
         }
 
         @Override
-        public <T extends ModelStoreAdapter> Optional<T> tryGetAdapter(ModelAdapterType<?, ? extends T, ?> adapterType) {
-                return adapters.tryGet(adapterType, adapterType.getModelStoreAdapterClass());
+        public <T extends ModelStoreAdapter> Optional<T> tryGetAdapter(Class<? extends T> adapterType) {
+                return AdapterUtils.tryGetAdapter(adapters, adapterType);
         }
 
         @Override
-        public <T extends ModelStoreAdapter> T getAdapter(ModelAdapterType<?, T, ?> adapterType) {
-                return adapters.get(adapterType, adapterType.getModelStoreAdapterClass());
+        public <T extends ModelStoreAdapter> T getAdapter(Class<T> adapterType) {
+                return AdapterUtils.getAdapter(adapters, adapterType);
         }
 
-        void addAdapter(AnyModelAdapterType adapterType, ModelStoreAdapter adapter) {
-                adapters.add(adapterType, adapter);
+        void addAdapter(ModelStoreAdapter adapter) {
+                adapters.add(adapter);
         }
 }
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/internal/SymbolEquivalenceClass.java b/subprojects/store/src/main/java/tools/refinery/store/model/internal/SymbolEquivalenceClass.java
index 5bf1b90d..136f2976 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/internal/SymbolEquivalenceClass.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/internal/SymbolEquivalenceClass.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model.internal;
 
 import tools.refinery.store.representation.Symbol;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/model/internal/VersionedInterpretation.java b/subprojects/store/src/main/java/tools/refinery/store/model/internal/VersionedInterpretation.java
index 6d82f5d7..86101ce3 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/model/internal/VersionedInterpretation.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/model/internal/VersionedInterpretation.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model.internal;
 
 import tools.refinery.store.map.Cursor;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/AbstractDomain.java b/subprojects/store/src/main/java/tools/refinery/store/representation/AbstractDomain.java
index 18903ead..52c740e8 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/AbstractDomain.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/AbstractDomain.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation;
 
 import java.util.Optional;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/AnyAbstractDomain.java b/subprojects/store/src/main/java/tools/refinery/store/representation/AnyAbstractDomain.java
index 4c428a1e..c354fab7 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/AnyAbstractDomain.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/AnyAbstractDomain.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation;
 
 public sealed interface AnyAbstractDomain permits AbstractDomain {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/AnySymbol.java b/subprojects/store/src/main/java/tools/refinery/store/representation/AnySymbol.java
index 20b9eead..b2377905 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/AnySymbol.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/AnySymbol.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation;
 
 public sealed interface AnySymbol permits Symbol {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/Symbol.java b/subprojects/store/src/main/java/tools/refinery/store/representation/Symbol.java
index 30b1c03f..cc748180 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/Symbol.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/Symbol.java
@@ -1,19 +1,25 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation;
 
 public record Symbol<T>(String name, int arity, Class<T> valueType, T defaultValue) implements AnySymbol {
         @Override
-        public boolean equals(Object o) {
-                return this == o;
+        public String toString() {
+                return "%s/%d".formatted(name, arity);
         }
 
-        @Override
-        public int hashCode() {
-                // Compare by identity to make hash table lookups more efficient.
-                return System.identityHashCode(this);
+        public static Symbol<Boolean> of(String name, int arity) {
+                return of(name, arity, Boolean.class, false);
         }
 
-        @Override
-        public String toString() {
-                return "%s/%d".formatted(name, arity);
+        public static <T> Symbol<T> of(String name, int arity, Class<T> valueType) {
+                return of(name, arity, valueType, null);
+        }
+
+        public static <T> Symbol<T> of(String name, int arity, Class<T> valueType, T defaultValue) {
+                return new Symbol<>(name, arity, valueType, defaultValue);
         }
 }
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/TruthValue.java b/subprojects/store/src/main/java/tools/refinery/store/representation/TruthValue.java
index b7893fd3..40baf9a5 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/TruthValue.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/TruthValue.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation;
 
 public enum TruthValue {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/TruthValueDomain.java b/subprojects/store/src/main/java/tools/refinery/store/representation/TruthValueDomain.java
index 29858bce..89f8dd19 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/TruthValueDomain.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/TruthValueDomain.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation;
 
 import java.util.Optional;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/CardinalityInterval.java b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/CardinalityInterval.java
index 273d0de7..704ca2fc 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/CardinalityInterval.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/CardinalityInterval.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 public sealed interface CardinalityInterval permits NonEmptyCardinalityInterval, EmptyCardinalityInterval {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/CardinalityIntervals.java b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/CardinalityIntervals.java
index e1a08bf9..ad16a3e8 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/CardinalityIntervals.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/CardinalityIntervals.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 public final class CardinalityIntervals {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/EmptyCardinalityInterval.java b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/EmptyCardinalityInterval.java
index ab3ad9d1..49911c29 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/EmptyCardinalityInterval.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/EmptyCardinalityInterval.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 public final class EmptyCardinalityInterval implements CardinalityInterval {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/FiniteUpperCardinality.java b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/FiniteUpperCardinality.java
index 381c8a57..82afdbbc 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/FiniteUpperCardinality.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/FiniteUpperCardinality.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 import org.jetbrains.annotations.NotNull;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/NonEmptyCardinalityInterval.java b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/NonEmptyCardinalityInterval.java
index 32b3786f..38bd53bf 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/NonEmptyCardinalityInterval.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/NonEmptyCardinalityInterval.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 import java.util.function.BinaryOperator;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/UnboundedUpperCardinality.java b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/UnboundedUpperCardinality.java
index 593bc322..a5634020 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/UnboundedUpperCardinality.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/UnboundedUpperCardinality.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 import org.jetbrains.annotations.NotNull;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/UpperCardinalities.java b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/UpperCardinalities.java
index d850fdc9..1e18dde0 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/UpperCardinalities.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/UpperCardinalities.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 public final class UpperCardinalities {
diff --git a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/UpperCardinality.java b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/UpperCardinality.java
index c6e31cb7..5dbaa922 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/UpperCardinality.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/representation/cardinality/UpperCardinality.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 public sealed interface UpperCardinality extends Comparable<UpperCardinality> permits FiniteUpperCardinality,
diff --git a/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple.java b/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple.java
index bf844c6d..6700417a 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple.java
@@ -1,28 +1,42 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.tuple;
 
-public sealed interface Tuple extends TupleLike permits Tuple0, Tuple1, Tuple2, TupleN {
-        @Override
-        default Tuple toTuple() {
-                return this;
-        }
+public sealed interface Tuple permits Tuple0, Tuple1, Tuple2, Tuple3, Tuple4, TupleN {
+        int getSize();
+
+        int get(int element);
 
-        static Tuple of() {
+        static Tuple0 of() {
                 return Tuple0.INSTANCE;
         }
 
-        static Tuple of(int value) {
+        static Tuple1 of(int value) {
                 return Tuple1.Cache.INSTANCE.getOrCreate(value);
         }
 
-        static Tuple of(int value1, int value2) {
+        static Tuple2 of(int value1, int value2) {
                 return new Tuple2(value1, value2);
         }
 
+        static Tuple3 of(int value1, int value2, int value3) {
+                return new Tuple3(value1, value2, value3);
+        }
+
+        static Tuple4 of(int value1, int value2, int value3, int value4) {
+                return new Tuple4(value1, value2, value3, value4);
+        }
+
         static Tuple of(int... values) {
                 return switch (values.length) {
                         case 0 -> of();
                         case 1 -> of(values[0]);
                         case 2 -> of(values[0], values[1]);
+                        case 3 -> of(values[0], values[1], values[2]);
+                        case 4 -> of(values[0], values[1], values[2], values[3]);
                         default -> new TupleN(values);
                 };
         }
diff --git a/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple0.java b/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple0.java
index 8eea5c3a..1451099c 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple0.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple0.java
@@ -1,7 +1,18 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.tuple;
 
-public record Tuple0() implements Tuple {
-        public static Tuple0 INSTANCE = new Tuple0();
+import static tools.refinery.store.tuple.TupleConstants.TUPLE_BEGIN;
+import static tools.refinery.store.tuple.TupleConstants.TUPLE_END;
+
+public final class Tuple0 implements Tuple {
+        public static final Tuple0 INSTANCE = new Tuple0();
+
+        private Tuple0() {
+        }
 
         @Override
         public int getSize() {
@@ -14,12 +25,7 @@ public record Tuple0() implements Tuple {
         }
 
         @Override
-        public int[] toArray() {
-                return new int[]{};
-        }
-
-        @Override
         public String toString() {
-                return "[]";
+                return TUPLE_BEGIN + TUPLE_END;
         }
 }
diff --git a/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple1.java b/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple1.java
index 07380966..cda145d7 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple1.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple1.java
@@ -1,10 +1,28 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.tuple;
 
 import tools.refinery.store.model.TupleHashProvider;
 
 import java.util.Arrays;
 
-public record Tuple1(int value0) implements Tuple {
+import static tools.refinery.store.tuple.TupleConstants.TUPLE_BEGIN;
+import static tools.refinery.store.tuple.TupleConstants.TUPLE_END;
+
+public final class Tuple1 implements Tuple {
+        private final int value0;
+
+        private Tuple1(int value0) {
+                this.value0 = value0;
+        }
+
+        public int value0() {
+                return value0;
+        }
+
         @Override
         public int getSize() {
                 return 1;
@@ -19,13 +37,21 @@ public record Tuple1(int value0) implements Tuple {
         }
 
         @Override
-        public int[] toArray() {
-                return new int[]{value0};
+        public String toString() {
+                return TUPLE_BEGIN + value0 + TUPLE_END;
         }
 
         @Override
-        public String toString() {
-                return "[" + value0 + "]";
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                Tuple1 tuple1 = (Tuple1) o;
+                return value0 == tuple1.value0;
+        }
+
+        @Override
+        public int hashCode() {
+                return 31 + value0;
         }
 
         /**
diff --git a/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple2.java b/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple2.java
index 0836a32d..b669674b 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple2.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple2.java
@@ -1,5 +1,12 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.tuple;
 
+import static tools.refinery.store.tuple.TupleConstants.*;
+
 public record Tuple2(int value0, int value1) implements Tuple {
         @Override
         public int getSize() {
@@ -16,12 +23,22 @@ public record Tuple2(int value0, int value1) implements Tuple {
         }
 
         @Override
-        public int[] toArray() {
-                return new int[]{value0, value1};
+        public String toString() {
+                return TUPLE_BEGIN + value0 + TUPLE_SEPARATOR + value1 + TUPLE_END;
         }
 
         @Override
-        public String toString() {
-                return "[" + value0 + ", " + value1 + "]";
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                Tuple2 tuple2 = (Tuple2) o;
+                return value0 == tuple2.value0 && value1 == tuple2.value1;
+        }
+
+        @Override
+        public int hashCode() {
+                int hash = 31 + value0;
+                hash = 31 * hash + value1;
+                return hash;
         }
 }
diff --git a/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple3.java b/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple3.java
new file mode 100644
index 00000000..542ed328
--- /dev/null
+++ b/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple3.java
@@ -0,0 +1,46 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.tuple;
+
+import static tools.refinery.store.tuple.TupleConstants.*;
+
+public record Tuple3(int value0, int value1, int value2) implements Tuple {
+        @Override
+        public int getSize() {
+                return 3;
+        }
+
+        @Override
+        public int get(int element) {
+                return switch (element) {
+                        case 0 -> value0;
+                        case 1 -> value1;
+                        case 2 -> value2;
+                        default -> throw new ArrayIndexOutOfBoundsException(element);
+                };
+        }
+
+        @Override
+        public String toString() {
+                return TUPLE_BEGIN + value0 + TUPLE_SEPARATOR + value1 + TUPLE_SEPARATOR + value2 + TUPLE_END;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                Tuple3 tuple3 = (Tuple3) o;
+                return value0 == tuple3.value0 && value1 == tuple3.value1 && value2 == tuple3.value2;
+        }
+
+        @Override
+        public int hashCode() {
+                int hash = 31 + value0;
+                hash = 31 * hash + value1;
+                hash = 31 * hash + value2;
+                return hash;
+        }
+}
diff --git a/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple4.java b/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple4.java
new file mode 100644
index 00000000..121a15f6
--- /dev/null
+++ b/subprojects/store/src/main/java/tools/refinery/store/tuple/Tuple4.java
@@ -0,0 +1,49 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.tuple;
+
+import static tools.refinery.store.tuple.TupleConstants.*;
+
+public record Tuple4(int value0, int value1, int value2, int value3) implements Tuple {
+        @Override
+        public int getSize() {
+                return 4;
+        }
+
+        @Override
+        public int get(int element) {
+                return switch (element) {
+                        case 0 -> value0;
+                        case 1 -> value1;
+                        case 2 -> value2;
+                        case 3 -> value3;
+                        default -> throw new ArrayIndexOutOfBoundsException(element);
+                };
+        }
+
+        @Override
+        public String toString() {
+                return TUPLE_BEGIN + value0 + TUPLE_SEPARATOR + value1 + TUPLE_SEPARATOR + value2 + TUPLE_SEPARATOR + value3 +
+                                TUPLE_END;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                Tuple4 tuple4 = (Tuple4) o;
+                return value0 == tuple4.value0 && value1 == tuple4.value1 && value2 == tuple4.value2 && value3 == tuple4.value3;
+        }
+
+        @Override
+        public int hashCode() {
+                int hash = 31 + value0;
+                hash = 31 * hash + value1;
+                hash = 31 * hash + value2;
+                hash = 31 * hash + value3;
+                return hash;
+        }
+}
diff --git a/subprojects/store/src/main/java/tools/refinery/store/tuple/TupleConstants.java b/subprojects/store/src/main/java/tools/refinery/store/tuple/TupleConstants.java
new file mode 100644
index 00000000..f7d27848
--- /dev/null
+++ b/subprojects/store/src/main/java/tools/refinery/store/tuple/TupleConstants.java
@@ -0,0 +1,17 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.store.tuple;
+
+final class TupleConstants {
+        public static final int MAX_STATIC_ARITY_TUPLE_SIZE = 4;
+        public static final String TUPLE_BEGIN = "[";
+        public static final String TUPLE_SEPARATOR = ", ";
+        public static final String TUPLE_END = "]";
+
+        private TupleConstants() {
+                throw new IllegalArgumentException("This is a static utility class an should not instantiated directly");
+        }
+}
diff --git a/subprojects/store/src/main/java/tools/refinery/store/tuple/TupleLike.java b/subprojects/store/src/main/java/tools/refinery/store/tuple/TupleLike.java
deleted file mode 100644
index 953ea9f8..00000000
--- a/subprojects/store/src/main/java/tools/refinery/store/tuple/TupleLike.java
+++ /dev/null
@@ -1,35 +0,0 @@
-package tools.refinery.store.tuple;
-
-import java.util.stream.Collectors;
-import java.util.stream.IntStream;
-
-public interface TupleLike {
-        int getSize();
-
-        int get(int element);
-
-        default int[] toArray() {
-                int size = getSize();
-                var array = new int[size];
-                for (int i = 0; i < size; i++) {
-                        array[i] = get(i);
-                }
-                return array;
-        }
-
-        default Tuple toTuple() {
-                return switch (getSize()) {
-                        case 0 -> Tuple.of();
-                        case 1 -> Tuple.of(get(0));
-                        case 2 -> Tuple.of(get(0), get(1));
-                        default -> Tuple.of(toArray());
-                };
-        }
-
-        static String toString(TupleLike tuple) {
-                var valuesString = IntStream.range(0, tuple.getSize())
-                                .mapToObj(i -> Integer.toString(tuple.get(i)))
-                                .collect(Collectors.joining(", "));
-                return "[" + valuesString + "]";
-        }
-}
diff --git a/subprojects/store/src/main/java/tools/refinery/store/tuple/TupleN.java b/subprojects/store/src/main/java/tools/refinery/store/tuple/TupleN.java
index c3aed847..b66af491 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/tuple/TupleN.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/tuple/TupleN.java
@@ -1,13 +1,23 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.tuple;
 
 import java.util.Arrays;
+import java.util.stream.Collectors;
 
-public record TupleN(int[] values) implements Tuple {
-        static final int CUSTOM_TUPLE_SIZE = 2;
+import static tools.refinery.store.tuple.TupleConstants.*;
 
-        public TupleN(int[] values) {
-                if (values.length < CUSTOM_TUPLE_SIZE)
-                        throw new IllegalArgumentException();
+public final class TupleN implements Tuple {
+        private final int[] values;
+
+        TupleN(int[] values) {
+                if (values.length < MAX_STATIC_ARITY_TUPLE_SIZE) {
+                        throw new IllegalArgumentException("Tuples of size at most %d must use static arity Tuple classes"
+                                        .formatted(MAX_STATIC_ARITY_TUPLE_SIZE));
+                }
                 this.values = Arrays.copyOf(values, values.length);
         }
 
@@ -22,18 +32,11 @@ public record TupleN(int[] values) implements Tuple {
         }
 
         @Override
-        public int[] toArray() {
-                return values;
-        }
-
-        @Override
         public String toString() {
-                return TupleLike.toString(this);
-        }
-
-        @Override
-        public int hashCode() {
-                return Arrays.hashCode(values);
+                var valuesString = Arrays.stream(values)
+                                .mapToObj(Integer::toString)
+                                .collect(Collectors.joining(TUPLE_SEPARATOR));
+                return TUPLE_BEGIN + valuesString + TUPLE_END;
         }
 
         @Override
@@ -47,4 +50,9 @@ public record TupleN(int[] values) implements Tuple {
                 TupleN other = (TupleN) obj;
                 return Arrays.equals(values, other.values);
         }
+
+        @Override
+        public int hashCode() {
+                return Arrays.hashCode(values);
+        }
 }
diff --git a/subprojects/store/src/main/java/tools/refinery/store/util/CollectionsUtil.java b/subprojects/store/src/main/java/tools/refinery/store/util/CollectionsUtil.java
index 841d0dfa..adecd79b 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/util/CollectionsUtil.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/util/CollectionsUtil.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.util;
 
 import java.util.Iterator;
diff --git a/subprojects/store/src/main/java/tools/refinery/store/util/CycleDetectingMapper.java b/subprojects/store/src/main/java/tools/refinery/store/util/CycleDetectingMapper.java
index 8a151d01..78ad2ad7 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/util/CycleDetectingMapper.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/util/CycleDetectingMapper.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.util;
 
 import java.util.*;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/MapUnitTests.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/MapUnitTests.java
index 77c62305..153f2e78 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/MapUnitTests.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/MapUnitTests.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests;
 
 import org.junit.jupiter.api.Test;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/CommitFuzzTest.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/CommitFuzzTest.java
index 1f9d022f..eabe5bd1 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/CommitFuzzTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/CommitFuzzTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests.fuzz;
 
 import static org.junit.jupiter.api.Assertions.fail;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/ContentEqualsFuzzTest.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/ContentEqualsFuzzTest.java
index 93ecfec3..b0502a2b 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/ContentEqualsFuzzTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/ContentEqualsFuzzTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests.fuzz;
 
 import org.junit.jupiter.api.Tag;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/DiffCursorFuzzTest.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/DiffCursorFuzzTest.java
index e6334224..8274336e 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/DiffCursorFuzzTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/DiffCursorFuzzTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests.fuzz;
 
 import static org.junit.jupiter.api.Assertions.fail;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MultiThreadFuzzTest.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MultiThreadFuzzTest.java
index 1ab431a8..ab2b9435 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MultiThreadFuzzTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MultiThreadFuzzTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests.fuzz;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MultiThreadTestRunnable.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MultiThreadTestRunnable.java
index f77f9ee5..502c8362 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MultiThreadTestRunnable.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MultiThreadTestRunnable.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests.fuzz;
 
 import java.util.ArrayList;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MutableFuzzTest.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MutableFuzzTest.java
index d40c49c4..32dde0da 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MutableFuzzTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MutableFuzzTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests.fuzz;
 
 import static org.junit.jupiter.api.Assertions.fail;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MutableImmutableCompareFuzzTest.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MutableImmutableCompareFuzzTest.java
index 410705a2..347c49be 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MutableImmutableCompareFuzzTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/MutableImmutableCompareFuzzTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests.fuzz;
 
 import static org.junit.jupiter.api.Assertions.fail;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/RestoreFuzzTest.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/RestoreFuzzTest.java
index 2e29a03f..f7b9d61e 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/RestoreFuzzTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/RestoreFuzzTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests.fuzz;
 
 import static org.junit.jupiter.api.Assertions.fail;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/SharedStoreFuzzTest.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/SharedStoreFuzzTest.java
index 914a0f63..4b4172d0 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/SharedStoreFuzzTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/SharedStoreFuzzTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests.fuzz;
 
 import java.util.HashMap;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/utils/FuzzTestUtils.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/utils/FuzzTestUtils.java
index e75d7f5a..a819d348 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/utils/FuzzTestUtils.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/utils/FuzzTestUtils.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests.fuzz.utils;
 
 import java.util.Arrays;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/utils/FuzzTestUtilsTest.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/utils/FuzzTestUtilsTest.java
index 72f2a46c..dc621574 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/utils/FuzzTestUtilsTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/fuzz/utils/FuzzTestUtilsTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests.fuzz.utils;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/map/tests/utils/MapTestEnvironment.java b/subprojects/store/src/test/java/tools/refinery/store/map/tests/utils/MapTestEnvironment.java
index 2d03ebaf..f861f496 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/map/tests/utils/MapTestEnvironment.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/map/tests/utils/MapTestEnvironment.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.map.tests.utils;
 
 import tools.refinery.store.map.*;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/model/hashtests/HashEfficiencyTest.java b/subprojects/store/src/test/java/tools/refinery/store/model/hashtests/HashEfficiencyTest.java
index bb083805..4d4f5e26 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/model/hashtests/HashEfficiencyTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/model/hashtests/HashEfficiencyTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model.hashtests;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/model/tests/ModelTest.java b/subprojects/store/src/test/java/tools/refinery/store/model/tests/ModelTest.java
index 9536a444..56b75804 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/model/tests/ModelTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/model/tests/ModelTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.model.tests;
 
 import org.junit.jupiter.api.Test;
@@ -9,27 +14,24 @@ import tools.refinery.store.tuple.Tuple;
 import static org.junit.jupiter.api.Assertions.*;
 
 class ModelTest {
+        private static final Symbol<Boolean> person = Symbol.of("Person", 1);
+        private static final Symbol<Integer> age = Symbol.of("age", 1, Integer.class);
+        private static final Symbol<Boolean> friend = Symbol.of("friend", 2);
+
         @Test
         void modelConstructionTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-
                 var store = ModelStore.builder().symbols(person, friend).build();
                 var symbols = store.getSymbols();
 
                 assertTrue(symbols.contains(person));
                 assertTrue(symbols.contains(friend));
 
-                var other = new Symbol<>("other", 2, Integer.class, null);
+                var other = Symbol.of("other", 2, Integer.class);
                 assertFalse(symbols.contains(other));
         }
 
         @Test
         void modelBuildingTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-
                 var store = ModelStore.builder().symbols(person, age, friend).build();
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
@@ -57,8 +59,6 @@ class ModelTest {
 
         @Test
         void modelBuildingArityFailTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-
                 var store = ModelStore.builder().symbols(person).build();
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
@@ -70,8 +70,6 @@ class ModelTest {
 
         @Test
         void modelBuildingNullFailTest() {
-                var age = new Symbol<>("age", 1, Integer.class, null);
-
                 var store = ModelStore.builder().symbols(age).build();
                 var model = store.createEmptyModel();
                 var ageInterpretation = model.getInterpretation(age);
@@ -84,10 +82,6 @@ class ModelTest {
 
         @Test
         void modelUpdateTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var age = new Symbol<>("age", 1, Integer.class, null);
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-
                 var store = ModelStore.builder().symbols(person, age, friend).build();
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
@@ -113,9 +107,6 @@ class ModelTest {
 
         @Test
         void restoreTest() {
-                var person = new Symbol<>("Person", 1, Boolean.class, false);
-                var friend = new Symbol<>("friend", 2, Boolean.class, false);
-
                 var store = ModelStore.builder().symbols(person, friend).build();
                 var model = store.createEmptyModel();
                 var personInterpretation = model.getInterpretation(person);
diff --git a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/CardinalityIntervalTest.java b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/CardinalityIntervalTest.java
index 96fdc49e..6a66fa84 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/CardinalityIntervalTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/CardinalityIntervalTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 import org.junit.jupiter.params.ParameterizedTest;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/CardinalityIntervalsTest.java b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/CardinalityIntervalsTest.java
index 4a9ef8da..9fe76159 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/CardinalityIntervalsTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/CardinalityIntervalsTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 import org.junit.jupiter.api.Test;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/EmptyCardinalityIntervalTest.java b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/EmptyCardinalityIntervalTest.java
index e8b77b9f..24a788a8 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/EmptyCardinalityIntervalTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/EmptyCardinalityIntervalTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 import org.junit.jupiter.api.Test;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/FiniteCardinalityIntervalTest.java b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/FiniteCardinalityIntervalTest.java
index 9a190818..6cf56fae 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/FiniteCardinalityIntervalTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/FiniteCardinalityIntervalTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 import org.junit.jupiter.api.Test;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/FiniteUpperCardinalityTest.java b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/FiniteUpperCardinalityTest.java
index 90c21759..7c641c47 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/FiniteUpperCardinalityTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/FiniteUpperCardinalityTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 import org.junit.jupiter.api.Test;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/UpperCardinalitiesTest.java b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/UpperCardinalitiesTest.java
index 3c7c0320..e61f7b36 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/UpperCardinalitiesTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/UpperCardinalitiesTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 import org.junit.jupiter.api.Test;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/UpperCardinalityTest.java b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/UpperCardinalityTest.java
index e87ce29b..10b4dd20 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/UpperCardinalityTest.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/representation/cardinality/UpperCardinalityTest.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.representation.cardinality;
 
 import org.junit.jupiter.params.ParameterizedTest;
diff --git a/subprojects/store/src/test/java/tools/refinery/store/util/CollectionsUtilTests.java b/subprojects/store/src/test/java/tools/refinery/store/util/CollectionsUtilTests.java
index 171be0e5..8d50fa8a 100644
--- a/subprojects/store/src/test/java/tools/refinery/store/util/CollectionsUtilTests.java
+++ b/subprojects/store/src/test/java/tools/refinery/store/util/CollectionsUtilTests.java
@@ -1,3 +1,8 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
 package tools.refinery.store.util;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;