diff --git a/com.avaloq.tools.ddk.check.runtime.core.test/META-INF/MANIFEST.MF b/com.avaloq.tools.ddk.check.runtime.core.test/META-INF/MANIFEST.MF
index 4d2ee84266..fda954c59a 100644
--- a/com.avaloq.tools.ddk.check.runtime.core.test/META-INF/MANIFEST.MF
+++ b/com.avaloq.tools.ddk.check.runtime.core.test/META-INF/MANIFEST.MF
@@ -13,7 +13,6 @@ Require-Bundle: org.eclipse.ui,
  com.google.guava,
  junit-jupiter-api,
  junit-jupiter-engine,
- junit-vintage-engine,
  junit-platform-suite-api
 Export-Package: com.avaloq.tools.ddk.check.runtime.test.core
 Import-Package: org.mockito,
diff --git a/com.avaloq.tools.ddk.check.test.runtime.tests/META-INF/MANIFEST.MF b/com.avaloq.tools.ddk.check.test.runtime.tests/META-INF/MANIFEST.MF
index 2b87675715..b34170162c 100644
--- a/com.avaloq.tools.ddk.check.test.runtime.tests/META-INF/MANIFEST.MF
+++ b/com.avaloq.tools.ddk.check.test.runtime.tests/META-INF/MANIFEST.MF
@@ -14,19 +14,14 @@ Require-Bundle: com.avaloq.tools.ddk.check.runtime.core,
  org.eclipse.xtext,
  org.eclipse.xtext.testing,
  org.eclipse.xtext.ui.testing,
- org.junit,
  org.eclipse.ui.workbench;resolution:=optional,
  org.eclipse.xtend.lib,
  org.eclipse.xtext.xbase.lib,
  junit-jupiter-api,
  junit-jupiter-engine,
+ junit-platform-suite-api,
  junit-vintage-engine
-Import-Package: org.junit.runner;version="4.5.0",
- org.junit.runner.manipulation;version="4.5.0",
- org.junit.runner.notification;version="4.5.0",
- org.junit.runners;version="4.5.0",
- org.junit.runners.model;version="4.5.0",
- org.hamcrest.core
+Import-Package: org.hamcrest.core
 Bundle-RequiredExecutionEnvironment: JavaSE-21
 Export-Package: com.avaloq.tools.ddk.check.test.runtime,
  com.avaloq.tools.ddk.check.test.runtime.tests,
diff --git a/com.avaloq.tools.ddk.check.test.runtime.tests/src/com/avaloq/tools/ddk/check/test/runtime/label/IssueLabelTest.xtend b/com.avaloq.tools.ddk.check.test.runtime.tests/src/com/avaloq/tools/ddk/check/test/runtime/label/IssueLabelTest.xtend
index 8d485dff38..5471340a03 100644
--- a/com.avaloq.tools.ddk.check.test.runtime.tests/src/com/avaloq/tools/ddk/check/test/runtime/label/IssueLabelTest.xtend
+++ b/com.avaloq.tools.ddk.check.test.runtime.tests/src/com/avaloq/tools/ddk/check/test/runtime/label/IssueLabelTest.xtend
@@ -15,10 +15,9 @@ import com.avaloq.tools.ddk.check.runtime.label.ICheckRuleLabelProvider
 import com.avaloq.tools.ddk.check.validation.LibraryChecksIssueCodes
 import com.google.inject.AbstractModule
 import com.google.inject.Guice
-import org.junit.Test
-
-import static org.junit.Assert.assertEquals
-import static org.junit.Assert.assertNotNull
+import org.junit.jupiter.api.Test
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 /**
  * End-to-end test for getting Check labels.
@@ -50,8 +49,8 @@ class IssueLabelTest {
       val label = checkRuleLabelProvider.getLabel(entry.key);
 
       // ASSERT
-      assertNotNull("Label should be returned for key " + entry.key, label);
-      assertEquals("Correct label should be returned for key " + entry.key, entry.value, label);
+      assertNotNull(label, "Label should be returned for key " + entry.key);
+      assertEquals( entry.value, label, "Correct label should be returned for key " + entry.key);
     }
   }
 }
diff --git a/com.avaloq.tools.ddk.check.test.runtime.tests/src/com/avaloq/tools/ddk/check/test/runtime/tests/CheckExecutionEnvironmentTestSuite.java b/com.avaloq.tools.ddk.check.test.runtime.tests/src/com/avaloq/tools/ddk/check/test/runtime/tests/CheckExecutionEnvironmentTestSuite.java
index 733fdd6a25..2d3fe6be7c 100644
--- a/com.avaloq.tools.ddk.check.test.runtime.tests/src/com/avaloq/tools/ddk/check/test/runtime/tests/CheckExecutionEnvironmentTestSuite.java
+++ b/com.avaloq.tools.ddk.check.test.runtime.tests/src/com/avaloq/tools/ddk/check/test/runtime/tests/CheckExecutionEnvironmentTestSuite.java
@@ -10,18 +10,19 @@
  *******************************************************************************/
 package com.avaloq.tools.ddk.check.test.runtime.tests;
 
-import org.junit.runner.RunWith;
-import org.junit.runners.Suite;
-
-import com.avaloq.tools.ddk.check.test.runtime.CheckConfigurationIsAppliedTest;
-import com.avaloq.tools.ddk.check.test.runtime.CheckExecutionEnvironmentProjectTest;
+import org.junit.platform.suite.api.SelectPackages;
+import org.junit.platform.suite.api.Suite;
 
 
 /**
- * Empty class serving only as holder for JUnit4 annotations.
+ * Junit5 version of test suites. does not implement the logic in our DiscerningSuite.
  */
-@RunWith(Suite.class)
-@Suite.SuiteClasses({CheckExecutionEnvironmentProjectTest.class, CheckConfigurationIsAppliedTest.class})
+@Suite
+@SelectPackages({
+// @Format-Off
+  "com.avaloq.tools.ddk.check.test.runtime"
+  // @Format-On
+})
 public class CheckExecutionEnvironmentTestSuite {
 
 }
diff --git a/com.avaloq.tools.ddk.check.test.runtime.tests/src/com/avaloq/tools/ddk/check/test/runtime/tests/CheckLibraryChecksTestSuite.java b/com.avaloq.tools.ddk.check.test.runtime.tests/src/com/avaloq/tools/ddk/check/test/runtime/tests/CheckLibraryChecksTestSuite.java
index 1ab95c20f5..b7e0d44f71 100644
--- a/com.avaloq.tools.ddk.check.test.runtime.tests/src/com/avaloq/tools/ddk/check/test/runtime/tests/CheckLibraryChecksTestSuite.java
+++ b/com.avaloq.tools.ddk.check.test.runtime.tests/src/com/avaloq/tools/ddk/check/test/runtime/tests/CheckLibraryChecksTestSuite.java
@@ -11,20 +11,18 @@
 
 package com.avaloq.tools.ddk.check.test.runtime.tests;
 
-import org.junit.runner.RunWith;
-import org.junit.runners.Suite;
-
-import com.avaloq.tools.ddk.check.test.runtime.label.IssueLabelTest;
+import org.junit.platform.suite.api.SelectPackages;
+import org.junit.platform.suite.api.Suite;
 
 
 /**
- * Empty class serving only as holder for JUnit4 annotations.
+ * Junit5 version of test suites. does not implement the logic in our DiscerningSuite.
  */
-@RunWith(Suite.class)
-@Suite.SuiteClasses({
+@Suite
+@SelectPackages({
 // @Format-Off
-  IssueLabelTest.class
-// @Format-On
+  "com.avaloq.tools.ddk.check.test.runtime.label"
+  // @Format-On
 })
 public class CheckLibraryChecksTestSuite {
 
diff --git a/com.avaloq.tools.ddk.typesystem.test/META-INF/MANIFEST.MF b/com.avaloq.tools.ddk.typesystem.test/META-INF/MANIFEST.MF
index 339f20bc2c..feac602e8c 100644
--- a/com.avaloq.tools.ddk.typesystem.test/META-INF/MANIFEST.MF
+++ b/com.avaloq.tools.ddk.typesystem.test/META-INF/MANIFEST.MF
@@ -11,7 +11,6 @@ Require-Bundle: com.google.inject,
  com.google.guava,
  junit-jupiter-api,
  junit-jupiter-engine,
- junit-vintage-engine,
  junit-platform-suite-api
 Export-Package: com.avaloq.tools.ddk.typesystem.test
 Automatic-Module-Name: com.avaloq.tools.ddk.typesystem.test