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+<!--
+  SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+
+  SPDX-License-Identifier: EPL-2.0
+-->
+
+# Contributing to Refinery
+
+## Setting up the development environment
+
+### With Eclipse IDE
+
+1. Download and install a _Java 17_ compatible JDK. For Windows, prefer OpenJDK builds from [Adoptium](https://adoptium.net/).
+
+2. Download and extract the [Eclipse IDE for Java and DSL Developers 2022-09](https://www.eclipse.org/downloads/packages/release/2022-09/r/eclipse-ide-java-and-dsl-developers) package.
+
+3. Launch Eclipse and create a new workspace.
+
+4. Open _Help > Install New Software..._ and install the following software from the _2022-09_ update site:
+    * _Modeling > Ecore Diagram Editor (SDK)_
+
+5. Open _Help > Eclipse Marketplace_ and install the following software:
+    * _EclEmma Java Code Coverage_
+    * _SonarLint_
+
+6. Open _Window > Preferences_ and set the following preferences:
+    * _General > Workspace > Text file encoding_ should be _UTF-8_.
+    * _General > Workspace > New text file line delimiter_ should be _Unix_.
+    * Add the JDK 17 to _Java > Installed JREs_.
+    * Make sure JDK 17 is selected for _JavaSE-17_ at _Java > Installed JREs > Execution Environments_.
+    * Set _Gradle > Java home_ to the `JAVA_HOME` directory (the directory which contains the `bin` directory) of JDK 17. Here, Buildship will show a yellow warning sign, which can be safely ignored.
+    * Set _Java > Compiler > JDK Compliance > Compiler compliance level_ to _17_.
+
+7. Clone the project Git repository but do not import it into Eclipse yet.
+
+8. Open a new terminal an run `./gradlew prepareEclipse` (`.\gradlew prepareEclipse` on Windows) in the cloned repository.
+    * This should complete without any compilation errors.
+    * If you get any errors about the JVM version, check whether the `JAVA_HOME` environment variable is set to the location of JDK. You can query the variable with `echo $JAVA_HOME` on Linux and `echo $Env:JAVA_HOME` in PowerShell on Windows. To set it, use `export JAVA_HOME=/java/path/here` or `$Env:JAVA_HOME="C:\java\path\here"`, respectively.
+    * If the build fails with a `Host name must not be empty` error, you [might need to remove the empty proxy configuration from your global `gradle.properties` file](https://stackoverflow.com/a/62128323).
+
+9. Select _File > Import... > Gradle > Existing Gradle Project_ and import the cloned repository in Eclipse.
+    * Make sure to select the root of the repository (containing this file) as the _Project root directory_ and that the _Gradle distribution_ is _Gradle wrapper_.
+    * If you have previously imported the project into Eclipse, this step will likely fail. In that case, you should remove the projects from Eclipse, run `git clean -fxd` in the repository, and start over from step 8.
+
+### With IntelliJ IDEA
+
+It is possible to import the project into IntelliJ IDEA, but it gives no editing help for Xtext (`*.xtext`), MWE2 (`*.mwe2`), and Xtend (`*.xtend`) and Ecore class diagrams (`*.aird`, `*.ecore`, `*.genmodel`).
+