diff --git a/buildSrc/src/main/groovy/eclipsebuild/AssembleTargetPlatformTask.groovy b/buildSrc/src/main/groovy/eclipsebuild/AssembleTargetPlatformTask.groovy
index be10f2144..cacc2b93b 100644
--- a/buildSrc/src/main/groovy/eclipsebuild/AssembleTargetPlatformTask.groovy
+++ b/buildSrc/src/main/groovy/eclipsebuild/AssembleTargetPlatformTask.groovy
@@ -108,7 +108,11 @@ abstract class AssembleTargetPlatformTask extends DefaultTask {
                 '-roaming',
                 '-nosplash',
                 '-consoleLog',
-                '-vmargs', '-Declipse.p2.mirror=false')
+                // the release train metadata contains XML entities larger than the JAXP defaults
+                // allow, and the SDK that runs the director does not raise the limits itself
+                '-vmargs', '-Declipse.p2.mirror=false',
+                '-Djdk.xml.maxGeneralEntitySizeLimit=0',
+                '-Djdk.xml.totalEntitySizeLimit=0')
 
             it.ignoreExitValue = true
         }
@@ -133,7 +137,11 @@ abstract class AssembleTargetPlatformTask extends DefaultTask {
                 '-roaming',
                 '-nosplash',
                 '-consoleLog',
-                '-vmargs', '-Declipse.p2.mirror=false')
+                // the release train metadata contains XML entities larger than the JAXP defaults
+                // allow, and the SDK that runs the director does not raise the limits itself
+                '-vmargs', '-Declipse.p2.mirror=false',
+                '-Djdk.xml.maxGeneralEntitySizeLimit=0',
+                '-Djdk.xml.totalEntitySizeLimit=0')
         }
     }
 }
diff --git a/buildSrc/src/main/groovy/eclipsebuild/BuildDefinitionPlugin.groovy b/buildSrc/src/main/groovy/eclipsebuild/BuildDefinitionPlugin.groovy
index b68e074d7..7b0fec986 100644
--- a/buildSrc/src/main/groovy/eclipsebuild/BuildDefinitionPlugin.groovy
+++ b/buildSrc/src/main/groovy/eclipsebuild/BuildDefinitionPlugin.groovy
@@ -392,7 +392,12 @@ class BuildDefinitionPlugin implements Plugin<Project> {
                     '-roaming',
                     '-nosplash',
                     '-consoleLog',
-                    '-vmargs', '-Declipse.p2.mirror=false')
+                    // the release train metadata contains XML entities larger than the JAXP
+                    // defaults allow, and the SDK that runs the director does not raise the
+                    // limits itself
+                    '-vmargs', '-Declipse.p2.mirror=false',
+                    '-Djdk.xml.maxGeneralEntitySizeLimit=0',
+                    '-Djdk.xml.totalEntitySizeLimit=0')
 
             it.ignoreExitValue = true
         }
@@ -417,7 +422,12 @@ class BuildDefinitionPlugin implements Plugin<Project> {
                     '-roaming',
                     '-nosplash',
                     '-consoleLog',
-                    '-vmargs', '-Declipse.p2.mirror=false')
+                    // the release train metadata contains XML entities larger than the JAXP
+                    // defaults allow, and the SDK that runs the director does not raise the
+                    // limits itself
+                    '-vmargs', '-Declipse.p2.mirror=false',
+                    '-Djdk.xml.maxGeneralEntitySizeLimit=0',
+                    '-Djdk.xml.totalEntitySizeLimit=0')
         }
     }
 
diff --git a/buildship.setup b/buildship.setup
index 3cc9b5071..9c4b40765 100644
--- a/buildship.setup
+++ b/buildship.setup
@@ -22,15 +22,17 @@
     <requirement
         name="org.eclipse.emf.ecoretools.design.feature.group"/>
     <repository
-        url="https://groovy.jfrog.io/artifactory/plugins-release/org/codehaus/groovy/groovy-eclipse-integration/5.7.0/e4.35"/>
+        url="https://groovy.jfrog.io/artifactory/plugins-release/org/codehaus/groovy/groovy-eclipse-integration/6.2.0/e4.40"/>
     <repository
-        url="https://groovy.jfrog.io/artifactory/plugins-release/org/codehaus/groovy/groovy-eclipse-integration/5.7.0/e4.34"/>
+        url="https://groovy.jfrog.io/artifactory/plugins-release/org/codehaus/groovy/groovy-eclipse-integration/6.2.0/e4.39"/>
     <repository
-        url="https://groovy.jfrog.io/artifactory/plugins-release/org/codehaus/groovy/groovy-eclipse-integration/5.7.0/e4.33"/>
+        url="https://groovy.jfrog.io/artifactory/plugins-release/org/codehaus/groovy/groovy-eclipse-integration/6.2.0/e4.38"/>
     <repository
-        url="https://groovy.jfrog.io/artifactory/plugins-release/org/codehaus/groovy/groovy-eclipse-integration/5.7.0/e4.32"/>
+        url="https://groovy.jfrog.io/artifactory/plugins-release/org/codehaus/groovy/groovy-eclipse-integration/6.2.0/e4.37"/>
     <repository
-        url="https://groovy.jfrog.io/artifactory/plugins-release/org/codehaus/groovy/groovy-eclipse-integration/5.7.0/e4.31"/>
+        url="https://groovy.jfrog.io/artifactory/plugins-release/org/codehaus/groovy/groovy-eclipse-integration/6.2.0/e4.36"/>
+    <repository
+        url="https://groovy.jfrog.io/artifactory/plugins-release/org/codehaus/groovy/groovy-eclipse-integration/6.2.0/e4.35"/>
   </setupTask>
   <setupTask
       xsi:type="setup:CompoundTask"
@@ -85,6 +87,13 @@
           xsi:type="jdt:JRETask"
           version="JavaSE-11"
           location="${jre.location-11}"/>
+      <setupTask
+          xsi:type="jdt:JRETask"
+          id="buildship.preferences.compiler.jre21"
+          version="JavaSE-21"
+          location="${jre.location-21}">
+        <description>The bundles that depend on the platform declare JavaSE-21, matching the newest supported Eclipse release. Register a strictly compatible JRE so their JRE containers resolve without a "no strictly compatible JRE" warning.</description>
+      </setupTask>
     </setupTask>
   </setupTask>
   <setupTask
@@ -100,22 +109,24 @@
         xsi:type="setup:PreferenceTask"
         id="buildship.preferences.compiler.source"
         key="instance/org.eclipse.jdt.core/org.eclipse.jdt.core.compiler.source"
-        value="1.8"/>
+        value="21"/>
     <setupTask
         xsi:type="setup:PreferenceTask"
         id="buildship.preferences.compiler.compilance"
         key="instance/org.eclipse.jdt.core/org.eclipse.jdt.core.compiler.compliance"
-        value="1.8"/>
+        value="21"/>
     <setupTask
         xsi:type="setup:PreferenceTask"
         id="buildship.preferences.compiler.codegen"
         key="instance/org.eclipse.jdt.core/org.eclipse.jdt.core.compiler.codegen.targetPlatform"
-        value="1.8"/>
+        value="21">
+      <description>Must match the execution environment the bundle manifests declare. PDE derives each project's compliance from its Bundle-RequiredExecutionEnvironment, and JDT compares that value against the class file version of the target platform bundles on the build path. A lower value makes JDT report "Incompatible .class files version in required binaries", which is a build path error and stops the project from compiling at all.</description>
+    </setupTask>
     <setupTask
         xsi:type="setup:PreferenceTask"
         id="buildship.preferences.compiler.goovycompilerlevel"
         key="instance/org.codehaus.groovy.eclipse.compilerResolver/groovy.compiler.level"
-        value="25">
+        value="30">
       <description>Align workspace Groovy compiler level to referenced libs</description>
     </setupTask>
     <setupTask
diff --git a/org.eclipse.buildship.branding/.classpath b/org.eclipse.buildship.branding/.classpath
index 2d325433f..0959d2a91 100644
--- a/org.eclipse.buildship.branding/.classpath
+++ b/org.eclipse.buildship.branding/.classpath
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21/"/>
 	<classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins"/>
 	<classpathentry kind="src" path="src/main/java"/>
 	<classpathentry kind="output" path="bin"/>
diff --git a/org.eclipse.buildship.branding/META-INF/MANIFEST.MF b/org.eclipse.buildship.branding/META-INF/MANIFEST.MF
index 74bfcefcf..9a3745c62 100644
--- a/org.eclipse.buildship.branding/META-INF/MANIFEST.MF
+++ b/org.eclipse.buildship.branding/META-INF/MANIFEST.MF
@@ -2,7 +2,8 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: Buildship, Eclipse Plug-ins for Gradle
 Bundle-SymbolicName: org.eclipse.buildship.branding;singleton:=true
+Automatic-Module-Name: org.eclipse.buildship.branding
 Bundle-Version: 3.1.12.qualifier
 Bundle-Vendor: Eclipse Buildship
-Bundle-RequiredExecutionEnvironment: JavaSE-11
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Bundle-ClassPath: .
diff --git a/org.eclipse.buildship.compat/META-INF/MANIFEST.MF b/org.eclipse.buildship.compat/META-INF/MANIFEST.MF
index 13fee5e4c..c45da7b8d 100644
--- a/org.eclipse.buildship.compat/META-INF/MANIFEST.MF
+++ b/org.eclipse.buildship.compat/META-INF/MANIFEST.MF
@@ -2,6 +2,7 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: Buildship, Eclipse Plug-ins for Gradle - Compatibility classes
 Bundle-SymbolicName: org.eclipse.buildship.compat;singleton:=true
+Automatic-Module-Name: org.eclipse.buildship.compat
 Bundle-Version: 3.1.12.qualifier
 Bundle-Vendor: Eclipse Buildship
 Bundle-RequiredExecutionEnvironment: JavaSE-1.8
diff --git a/org.eclipse.buildship.core.test/.classpath b/org.eclipse.buildship.core.test/.classpath
index b7d88c3e3..fbe6cba55 100644
--- a/org.eclipse.buildship.core.test/.classpath
+++ b/org.eclipse.buildship.core.test/.classpath
@@ -1,5 +1,5 @@
 <classpath>
-  <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER">
+  <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21">
     <attributes>
       <attribute name="module" value="true"/>
     </attributes>
diff --git a/org.eclipse.buildship.core.test/META-INF/MANIFEST.MF b/org.eclipse.buildship.core.test/META-INF/MANIFEST.MF
index 04100a536..2e0773d8f 100644
--- a/org.eclipse.buildship.core.test/META-INF/MANIFEST.MF
+++ b/org.eclipse.buildship.core.test/META-INF/MANIFEST.MF
@@ -2,9 +2,10 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: Buildship, Eclipse Plug-ins for Gradle - Core Test
 Bundle-SymbolicName: org.eclipse.buildship.core.test;singleton:=true
+Automatic-Module-Name: org.eclipse.buildship.core.test
 Bundle-Version: 3.1.12.qualifier
 Bundle-Vendor: Eclipse Buildship
-Bundle-RequiredExecutionEnvironment: JavaSE-11
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Fragment-Host: org.eclipse.buildship.core
 Comment: junit has to be a required bundle, otherwise the tests won't launch for headless builds
 Require-Bundle: junit-platform-engine
@@ -36,7 +37,6 @@ Bundle-ClassPath: .,
  lib/groovy-test-junit5-3.0.19.jar,
  lib/groovy-testng-3.0.19.jar,
  lib/groovy-xml-3.0.19.jar,
- lib/hamcrest-core-1.3.jar,
  lib/javaparser-core-3.25.4.jar,
  lib/jcommander-1.78.jar,
  lib/jline-2.14.6.jar,
diff --git a/org.eclipse.buildship.core/.classpath b/org.eclipse.buildship.core/.classpath
index 811af0f63..72b903a65 100644
--- a/org.eclipse.buildship.core/.classpath
+++ b/org.eclipse.buildship.core/.classpath
@@ -1,5 +1,5 @@
 <classpath>
-  <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+  <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21"/>
   <classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins"/>
   <classpathentry kind="src" path="src/main/java"/>
   <classpathentry kind="src" path="src/main/resources/"/>
diff --git a/org.eclipse.buildship.core/META-INF/MANIFEST.MF b/org.eclipse.buildship.core/META-INF/MANIFEST.MF
index a6cedd919..0ad934fd6 100644
--- a/org.eclipse.buildship.core/META-INF/MANIFEST.MF
+++ b/org.eclipse.buildship.core/META-INF/MANIFEST.MF
@@ -2,9 +2,10 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: Buildship, Eclipse Plug-ins for Gradle - Core
 Bundle-SymbolicName: org.eclipse.buildship.core;singleton:=true
+Automatic-Module-Name: org.eclipse.buildship.core
 Bundle-Version: 3.1.12.qualifier
 Bundle-Vendor: Eclipse Buildship
-Bundle-RequiredExecutionEnvironment: JavaSE-11
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Bundle-Activator: org.eclipse.buildship.core.internal.CorePlugin
 Require-Bundle: org.eclipse.core.expressions,
  org.eclipse.core.filesystem,
diff --git a/org.eclipse.buildship.dcl.provider/.classpath b/org.eclipse.buildship.dcl.provider/.classpath
index 19fb46034..73a73fcae 100644
--- a/org.eclipse.buildship.dcl.provider/.classpath
+++ b/org.eclipse.buildship.dcl.provider/.classpath
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-    <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER">
+    <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21">
         <attributes>
             <attribute name="module" value="true"/>
         </attributes>
diff --git a/org.eclipse.buildship.dcl.provider/META-INF/MANIFEST.MF b/org.eclipse.buildship.dcl.provider/META-INF/MANIFEST.MF
index 0f83dc494..e67654792 100644
--- a/org.eclipse.buildship.dcl.provider/META-INF/MANIFEST.MF
+++ b/org.eclipse.buildship.dcl.provider/META-INF/MANIFEST.MF
@@ -12,5 +12,5 @@ Require-Bundle: org.eclipse.core.runtime,
  org.eclipse.lsp4e,
  org.eclipse.jdt.launching,
  org.eclipse.buildship.core
-Bundle-RequiredExecutionEnvironment: JavaSE-17
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Automatic-Module-Name: org.eclipse.buildship.dcl.provider
diff --git a/org.eclipse.buildship.dcl.provider/build.properties b/org.eclipse.buildship.dcl.provider/build.properties
index 2dfa377d3..779193616 100644
--- a/org.eclipse.buildship.dcl.provider/build.properties
+++ b/org.eclipse.buildship.dcl.provider/build.properties
@@ -1,4 +1,7 @@
-bin.includes = META-INF/,\
+source.. = src/main/java/
+output.. = bin/
+bin.includes = .,\
+               META-INF/,\
                plugin.xml,\
                grammar/,\
                gradle-dcl.tmLanguage.json,\
diff --git a/org.eclipse.buildship.gradleprop.provider/.classpath b/org.eclipse.buildship.gradleprop.provider/.classpath
index dfb22bbfc..fb8267a0a 100644
--- a/org.eclipse.buildship.gradleprop.provider/.classpath
+++ b/org.eclipse.buildship.gradleprop.provider/.classpath
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER">
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21">
 		<attributes>
 			<attribute name="module" value="true"/>
 		</attributes>
diff --git a/org.eclipse.buildship.gradleprop.provider/META-INF/MANIFEST.MF b/org.eclipse.buildship.gradleprop.provider/META-INF/MANIFEST.MF
index 82c933369..737e5c605 100644
--- a/org.eclipse.buildship.gradleprop.provider/META-INF/MANIFEST.MF
+++ b/org.eclipse.buildship.gradleprop.provider/META-INF/MANIFEST.MF
@@ -3,7 +3,7 @@ Bundle-ManifestVersion: 2
 Bundle-Name: Provider
 Bundle-SymbolicName: org.eclipse.buildship.gradleprop.provider;singleton:=true
 Bundle-Version: 3.1.12.qualifier
-Bundle-RequiredExecutionEnvironment: JavaSE-17
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Require-Bundle: org.eclipse.core.contenttype,
  org.eclipse.ui,
  org.eclipse.lsp4e,
diff --git a/org.eclipse.buildship.gradleprop.test/.classpath b/org.eclipse.buildship.gradleprop.test/.classpath
index e15443bf3..1448bfa24 100644
--- a/org.eclipse.buildship.gradleprop.test/.classpath
+++ b/org.eclipse.buildship.gradleprop.test/.classpath
@@ -1,5 +1,5 @@
 <classpath>
-  <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+  <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21"/>
   <classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins"/>
   <classpathentry kind="src" path="src/main/java"/>
   <classpathentry kind="output" path="bin"/>
diff --git a/org.eclipse.buildship.gradleprop.test/META-INF/MANIFEST.MF b/org.eclipse.buildship.gradleprop.test/META-INF/MANIFEST.MF
index dccc730d8..18994043b 100644
--- a/org.eclipse.buildship.gradleprop.test/META-INF/MANIFEST.MF
+++ b/org.eclipse.buildship.gradleprop.test/META-INF/MANIFEST.MF
@@ -4,7 +4,7 @@ Bundle-Name: Buildship, Eclipse Plug-ins for Gradle - gradle.properties editor t
 Bundle-SymbolicName: org.eclipse.buildship.gradleprop.test;singleton:=true
 Bundle-Version: 3.1.12.qualifier
 Bundle-Vendor: Eclipse Buildship
-Bundle-RequiredExecutionEnvironment: JavaSE-11
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Fragment-Host: org.eclipse.buildship.gradleprop.provider
 Comment: junit has to be a required bundle, otherwise the tests won't launch for headless builds
 Require-Bundle: org.eclipse.swtbot.eclipse.finder,
diff --git a/org.eclipse.buildship.oomph.edit/.classpath b/org.eclipse.buildship.oomph.edit/.classpath
index 098e233d7..30e203086 100644
--- a/org.eclipse.buildship.oomph.edit/.classpath
+++ b/org.eclipse.buildship.oomph.edit/.classpath
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="src" path="src/main/java-generated"/>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21"/>
 	<classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins">
 		<accessrules>
 			<accessrule kind="accessible" pattern="org/eclipse/oomph/**"/>
diff --git a/org.eclipse.buildship.oomph.edit/META-INF/MANIFEST.MF b/org.eclipse.buildship.oomph.edit/META-INF/MANIFEST.MF
index 221036bb9..c4a0c0f1a 100644
--- a/org.eclipse.buildship.oomph.edit/META-INF/MANIFEST.MF
+++ b/org.eclipse.buildship.oomph.edit/META-INF/MANIFEST.MF
@@ -9,7 +9,7 @@ Bundle-ClassPath: .
 Bundle-Activator: org.eclipse.buildship.oomph.provider.GradleImportEditPlugin$Implementation
 Bundle-ActivationPolicy: lazy
 Bundle-Localization: plugin
-Bundle-RequiredExecutionEnvironment: JavaSE-11
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Require-Bundle: org.eclipse.core.runtime,
  org.eclipse.emf.ecore;bundle-version="[2.10.0,3.0.0)",
  org.eclipse.emf.edit;bundle-version="[2.10.0,3.0.0)";visibility:=reexport,
diff --git a/org.eclipse.buildship.oomph.test/.classpath b/org.eclipse.buildship.oomph.test/.classpath
index 5b2743960..03f7ce422 100644
--- a/org.eclipse.buildship.oomph.test/.classpath
+++ b/org.eclipse.buildship.oomph.test/.classpath
@@ -1,6 +1,6 @@
 <classpath>
   <classpathentry kind="src" path="src/main/groovy"/>
-  <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-11"/>
+  <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21"/>
   <classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins"/>
   <classpathentry kind="con" path="GROOVY_DSL_SUPPORT"/>
   <classpathentry kind="output" path="bin"/>
diff --git a/org.eclipse.buildship.oomph.test/META-INF/MANIFEST.MF b/org.eclipse.buildship.oomph.test/META-INF/MANIFEST.MF
index 65e4bc4ad..5ccab932e 100644
--- a/org.eclipse.buildship.oomph.test/META-INF/MANIFEST.MF
+++ b/org.eclipse.buildship.oomph.test/META-INF/MANIFEST.MF
@@ -4,7 +4,7 @@ Bundle-Name: Buildship, Eclipse Plug-ins for Gradle - Oomph Import Setup Task UI
 Bundle-SymbolicName: org.eclipse.buildship.oomph.test;singleton:=true
 Bundle-Version: 3.1.12.qualifier
 Bundle-Vendor: Eclipse Buildship
-Bundle-RequiredExecutionEnvironment: JavaSE-11
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Fragment-Host: org.eclipse.buildship.oomph
 Automatic-Module-Name: org.eclipse.buildship.oomph.test
 Require-Bundle: org.eclipse.oomph.setup.core,
@@ -54,7 +54,6 @@ Bundle-ClassPath: .,
  lib/groovy-test-junit5-3.0.19.jar,
  lib/groovy-testng-3.0.19.jar,
  lib/groovy-xml-3.0.19.jar,
- lib/hamcrest-core-1.3.jar,
  lib/javaparser-core-3.25.4.jar,
  lib/jcommander-1.78.jar,
  lib/jline-2.14.6.jar,
diff --git a/org.eclipse.buildship.oomph.test/build.properties b/org.eclipse.buildship.oomph.test/build.properties
index 0b5ee95e1..ba47c2426 100644
--- a/org.eclipse.buildship.oomph.test/build.properties
+++ b/org.eclipse.buildship.oomph.test/build.properties
@@ -1,5 +1,4 @@
-source.. = src/main/groovy/,\
-           src/main/resources/
+source.. = src/main/groovy/
 output.. = bin/
 bin.includes = .,\
                lib/,\
diff --git a/org.eclipse.buildship.oomph/.classpath b/org.eclipse.buildship.oomph/.classpath
index f80b92ef6..31b6b2683 100644
--- a/org.eclipse.buildship.oomph/.classpath
+++ b/org.eclipse.buildship.oomph/.classpath
@@ -3,7 +3,7 @@
 	<classpathentry kind="src" path="src/main/java-generated"/>
 	<classpathentry kind="src" path="src/main/resources"/>
 	<classpathentry kind="src" path="src/main/java"/>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21"/>
 	<classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins">
 		<accessrules>
 			<accessrule kind="accessible" pattern="org/eclipse/oomph/**"/>
diff --git a/org.eclipse.buildship.oomph/META-INF/MANIFEST.MF b/org.eclipse.buildship.oomph/META-INF/MANIFEST.MF
index 6c503cc49..57db2fb12 100644
--- a/org.eclipse.buildship.oomph/META-INF/MANIFEST.MF
+++ b/org.eclipse.buildship.oomph/META-INF/MANIFEST.MF
@@ -8,7 +8,7 @@ Bundle-Version: 3.1.12.qualifier
 Bundle-ClassPath: .
 Bundle-ActivationPolicy: lazy
 Bundle-Localization: plugin
-Bundle-RequiredExecutionEnvironment: JavaSE-11
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Require-Bundle: org.eclipse.core.runtime,
  org.eclipse.emf.ecore;bundle-version="[2.10.0,3.0.0)";visibility:=reexport,
  org.eclipse.oomph.resources;bundle-version="[1.1.0,2.0.0)";visibility:=reexport,
diff --git a/org.eclipse.buildship.oomph/build.properties b/org.eclipse.buildship.oomph/build.properties
index b99b31e8e..42bf5eb78 100644
--- a/org.eclipse.buildship.oomph/build.properties
+++ b/org.eclipse.buildship.oomph/build.properties
@@ -12,5 +12,6 @@ bin.includes = .,\
                plugin.properties
 jars.compile.order = .
 source.. = src/main/java-generated/,\
+           src/main/java/,\
            src/main/resources/
 output.. = bin/
diff --git a/org.eclipse.buildship.ui.test/.classpath b/org.eclipse.buildship.ui.test/.classpath
index b07285415..32b5953a0 100644
--- a/org.eclipse.buildship.ui.test/.classpath
+++ b/org.eclipse.buildship.ui.test/.classpath
@@ -1,5 +1,5 @@
 <classpath>
-  <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+  <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21"/>
   <classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins"/>
   <classpathentry exported="true" kind="con" path="GROOVY_DSL_SUPPORT"/>
   <classpathentry kind="src" path="src/main/groovy"/>
diff --git a/org.eclipse.buildship.ui.test/META-INF/MANIFEST.MF b/org.eclipse.buildship.ui.test/META-INF/MANIFEST.MF
index 0678a23e0..b737e56b8 100644
--- a/org.eclipse.buildship.ui.test/META-INF/MANIFEST.MF
+++ b/org.eclipse.buildship.ui.test/META-INF/MANIFEST.MF
@@ -2,9 +2,10 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: Buildship, Eclipse Plug-ins for Gradle - UI Test
 Bundle-SymbolicName: org.eclipse.buildship.ui.test;singleton:=true
+Automatic-Module-Name: org.eclipse.buildship.ui.test
 Bundle-Version: 3.1.12.qualifier
 Bundle-Vendor: Eclipse Buildship
-Bundle-RequiredExecutionEnvironment: JavaSE-11
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Fragment-Host: org.eclipse.buildship.ui
 Comment: junit has to be a required bundle, otherwise the tests won't launch for headless builds
 Require-Bundle: org.eclipse.swtbot.eclipse.finder,
@@ -53,7 +54,6 @@ Bundle-ClassPath: .,
  lib/groovy-test-junit5-3.0.19.jar,
  lib/groovy-testng-3.0.19.jar,
  lib/groovy-xml-3.0.19.jar,
- lib/hamcrest-core-1.3.jar,
  lib/javaparser-core-3.25.4.jar,
  lib/jcommander-1.78.jar,
  lib/jline-2.14.6.jar,
diff --git a/org.eclipse.buildship.ui/.classpath b/org.eclipse.buildship.ui/.classpath
index dddac7bb9..db047cb1b 100644
--- a/org.eclipse.buildship.ui/.classpath
+++ b/org.eclipse.buildship.ui/.classpath
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21"/>
 	<classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins"/>
 	<classpathentry kind="src" path="src/main/java"/>
 	<classpathentry kind="src" path="src/main/resources"/>
diff --git a/org.eclipse.buildship.ui/META-INF/MANIFEST.MF b/org.eclipse.buildship.ui/META-INF/MANIFEST.MF
index fe958604a..5c408ace1 100644
--- a/org.eclipse.buildship.ui/META-INF/MANIFEST.MF
+++ b/org.eclipse.buildship.ui/META-INF/MANIFEST.MF
@@ -2,9 +2,10 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: Buildship, Eclipse Plug-ins for Gradle - UI
 Bundle-SymbolicName: org.eclipse.buildship.ui;singleton:=true
+Automatic-Module-Name: org.eclipse.buildship.ui
 Bundle-Version: 3.1.12.qualifier
 Bundle-Vendor: Eclipse Buildship
-Bundle-RequiredExecutionEnvironment: JavaSE-11
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Bundle-Activator: org.eclipse.buildship.ui.internal.UiPlugin
 Require-Bundle: org.eclipse.buildship.core,
  org.eclipse.core.runtime,
diff --git a/org.gradle.toolingapi/.classpath b/org.gradle.toolingapi/.classpath
index cd57fbd10..811690e5f 100644
--- a/org.gradle.toolingapi/.classpath
+++ b/org.gradle.toolingapi/.classpath
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
 	<classpathentry kind="output" path="bin/default"/>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-11/"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8/"/>
 	<classpathentry sourcepath="org.gradle.toolingapi.source_8.9.0.jar" kind="lib" path="org.gradle.toolingapi_8.9.0.jar" exported="true"/>
 </classpath>
diff --git a/org.gradle.toolingapi/META-INF/MANIFEST.MF b/org.gradle.toolingapi/META-INF/MANIFEST.MF
index 2bdc970ec..43a5ab56a 100644
--- a/org.gradle.toolingapi/META-INF/MANIFEST.MF
+++ b/org.gradle.toolingapi/META-INF/MANIFEST.MF
@@ -3,6 +3,7 @@ Bundle-ManifestVersion: 2
 Bundle-Name: Gradle Tooling API
 Bundle-Vendor: Gradle Inc.
 Bundle-SymbolicName: org.gradle.toolingapi
+Automatic-Module-Name: org.gradle.toolingapi
 Bundle-ClassPath: org.gradle.toolingapi_8.9.0.jar
 Bundle-RequiredExecutionEnvironment: JavaSE-1.8
 Import-Package: org.slf4j;version="1.7.2"
@@ -31,4 +32,4 @@ Export-Package: org.gradle.api;version="8.9.0",
  org.gradle.tooling.model.idea;version="8.9.0",
  org.gradle.tooling.model.java;version="8.9.0",
  org.gradle.tooling.model.kotlin.dsl;version="8.9.0"
-Bundle-Version: 3.1.12.qualifier
+Bundle-Version: 8.9.0.qualifier
diff --git a/org.gradle.toolingapi/build.properties b/org.gradle.toolingapi/build.properties
new file mode 100644
index 000000000..ee38181ca
--- /dev/null
+++ b/org.gradle.toolingapi/build.properties
@@ -0,0 +1,7 @@
+# This bundle wraps the Gradle Tooling API jar and is assembled by
+# eclipsebuild.jar.ExistingJarBundlePlugin, not by PDE. The file exists so that PDE does not
+# report the project as misconfigured. Keep the jar name in sync with toolingApiVersion in
+# gradle.properties, the same way Bundle-ClassPath and .classpath are.
+bin.includes = META-INF/,\
+               org.gradle.toolingapi_8.9.0.jar,\
+               about.html
diff --git a/org.gradle.toolingapi/resources/template/manifest-template.txt b/org.gradle.toolingapi/resources/template/manifest-template.txt
index 8c595dd44..150a08276 100644
--- a/org.gradle.toolingapi/resources/template/manifest-template.txt
+++ b/org.gradle.toolingapi/resources/template/manifest-template.txt
@@ -3,6 +3,7 @@ Bundle-ManifestVersion: 2
 Bundle-Name: Gradle Tooling API
 Bundle-Vendor: Gradle Inc.
 Bundle-SymbolicName: org.gradle.toolingapi
+Automatic-Module-Name: org.gradle.toolingapi
 Bundle-ClassPath: .
 Bundle-RequiredExecutionEnvironment: JavaSE-1.8
 Import-Package: org.slf4j;version="1.7.2"