diff --git a/Jenkinsfile b/Jenkinsfile
index 7a45b390..728cf98f 100644
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -74,9 +74,9 @@ pipeline {
                         }
                      }
                 }
-                stage('Trigger Java11 build') {
+                stage('Trigger Java21 build') {
                     steps {
-                        build wait: false, job: 'glsp-server-java11'
+                        build wait: false, job: 'glsp-server-java21'
                     }
                 }
             }
diff --git a/releng/org.eclipse.glsp.repository/pom.xml b/releng/org.eclipse.glsp.repository/pom.xml
index 0b89028f..b8c2aef5 100644
--- a/releng/org.eclipse.glsp.repository/pom.xml
+++ b/releng/org.eclipse.glsp.repository/pom.xml
@@ -95,7 +95,7 @@
 						<artifactId>tycho-eclipserun-plugin</artifactId>
 						<version>${tycho.version}</version>
 						<configuration>
-							<executionEnvironment>JavaSE-17</executionEnvironment>
+							<executionEnvironment>JavaSE-11</executionEnvironment>
 							<!-- IMPORTANT: DO NOT split the arg line -->
 							<appArgLine>-application org.eclipse.ant.core.antRunner -buildfile packaging-p2composite.ant p2.composite.add -Dsite.label=${p2.site.label} -Dproject.build.directory=${project.build.directory} -DunqualifiedVersion=${unqualifiedVersion} -DbuildQualifier=${buildQualifier} -Dsoftware.download.area=${rsync.local.dir}</appArgLine>
 							<repositories>