chore: add copyright headers

Make sure we obey the REUSE (https://reuse.software) specification and the
origin, copyright owner, and license of all files are clearly marked.

The whole project is under the EPL-2.0, except for trivial files where copyright
is not applicable that are marked with the CC0-1.0 license. Moreover, code
included from third parties is also available under the respective license.

chore: add CONTRIBUTORS.md

List all authors and supporting organizations in accordance with the REUSE
specification.

32 files changed, 163 insertions, 0 deletions

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..12e39e55 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
@@ -1,4 +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/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 d40e50af..1924f661 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;
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
index a055e755..27802e0c 100644
--- 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
@@ -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.jetty.server.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 47e8de7c..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;
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
index abbcbd53..699a09ab 100644
--- 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
@@ -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;
 
 import org.eclipse.xtext.ide.ExecutorServiceProvider;
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..f7d33e9e 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
@@ -1,3 +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.gson.Gson;
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;