diff --git a/.github/workflows/deploy.yml b/.github/workflows/deploy.yml
index 1b438c7..e88312f 100644
--- a/.github/workflows/deploy.yml
+++ b/.github/workflows/deploy.yml
@@ -16,10 +16,10 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Set up JDK 11
+      - name: Set up JDK 21
         uses: actions/setup-java@v4
         with:
-          java-version: 11
+          java-version: 21
           distribution: "temurin"
           server-id: openconext-releases
           server-username: MAVEN_USERNAME
@@ -49,10 +49,10 @@ jobs:
           exit 1
         if: github.event_name != 'workflow_dispatch' && steps.versioncheck.outputs.version != github.ref_name
 
-      - name: Set up JDK 11 for snapshots
+      - name: Set up JDK 21 for snapshots
         uses: actions/setup-java@v4
         with:
-          java-version: "11"
+          java-version: "21"
           distribution: "temurin"
           cache: "maven"
           server-id: openconext-snapshots
@@ -60,10 +60,10 @@ jobs:
           server-password: MAVEN_PASSWORD
         if: ( endsWith(steps.versioncheck.outputs.version, '-SNAPSHOT'))
 
-      - name: Set up JDK 11 for releases
+      - name: Set up JDK 21 for releases
         uses: actions/setup-java@v4
         with:
-          java-version: "11"
+          java-version: "21"
           distribution: "temurin"
           cache: "maven"
           server-id: openconext-releases
diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
index d636835..38b94c9 100644
--- a/.github/workflows/maven.yml
+++ b/.github/workflows/maven.yml
@@ -5,9 +5,9 @@ name: Verify
 
 on:
   push:
-    branches: [ master ]
+    branches: [ main ]
   pull_request:
-    branches: [ master ]
+    branches: [ main ]
 
 jobs:
   build:
@@ -23,7 +23,7 @@ jobs:
 
     - uses: actions/setup-java@v2
       with:
-        java-version: '11'
+        java-version: '21'
         distribution: 'adopt'
         cache: 'maven'
 
diff --git a/oidc-playground-client/build.sh b/oidc-playground-client/build.sh
index 3b62352..a3416cc 100755
--- a/oidc-playground-client/build.sh
+++ b/oidc-playground-client/build.sh
@@ -2,4 +2,6 @@
 rm -Rf build/*
 rm -Rf target/*
 export NODE_OPTIONS=--openssl-legacy-provider
+source $NVM_DIR/nvm.sh
+nvm use
 yarn install && CI=true yarn test && yarn build
diff --git a/oidc-playground-client/pom.xml b/oidc-playground-client/pom.xml
index df7da7e..13945a9 100644
--- a/oidc-playground-client/pom.xml
+++ b/oidc-playground-client/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>org.openconext</groupId>
         <artifactId>oidc-playground</artifactId>
-        <version>3.0.2-SNAPSHOT</version>
+        <version>4.0.0-SNAPSHOT</version>
         <relativePath>../pom.xml</relativePath>
     </parent>
 
diff --git a/oidc-playground-server/docker/Dockerfile b/oidc-playground-server/docker/Dockerfile
index 6db5b00..d05aa42 100644
--- a/oidc-playground-server/docker/Dockerfile
+++ b/oidc-playground-server/docker/Dockerfile
@@ -1,3 +1,3 @@
-FROM eclipse-temurin:11-jdk-alpine
+FROM eclipse-temurin:21-jdk-alpine
 COPY target/*.jar app.jar
 ENTRYPOINT ["java","-jar","/app.jar"]
diff --git a/oidc-playground-server/pom.xml b/oidc-playground-server/pom.xml
index e2aac79..068fb59 100644
--- a/oidc-playground-server/pom.xml
+++ b/oidc-playground-server/pom.xml
@@ -6,7 +6,7 @@
     <parent>
         <groupId>org.openconext</groupId>
         <artifactId>oidc-playground</artifactId>
-        <version>3.0.2-SNAPSHOT</version>
+        <version>4.0.0-SNAPSHOT</version>
         <relativePath>../pom.xml</relativePath>
     </parent>
 
@@ -118,19 +118,20 @@
             <plugin>
                 <groupId>pl.project13.maven</groupId>
                 <artifactId>git-commit-id-plugin</artifactId>
+                <version>4.9.10</version>
             </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>3.9.0</version>
+                <version>3.13.0</version>
                 <configuration>
-                    <release>11</release>
+                    <release>21</release>
                 </configuration>
             </plugin>
             <plugin>
                 <groupId>org.jacoco</groupId>
                 <artifactId>jacoco-maven-plugin</artifactId>
-                <version>0.8.7</version>
+                <version>0.8.12</version>
                 <executions>
                     <execution>
                         <goals>
@@ -149,7 +150,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-enforcer-plugin</artifactId>
-                <version>3.3.0</version>
+                <version>3.5.0</version>
                 <executions>
                     <execution>
                         <id>enforce-versions</id>
@@ -162,7 +163,7 @@
                                     <version>3.8.4</version>
                                 </requireMavenVersion>
                                 <requireJavaVersion>
-                                    <version>11</version>
+                                    <version>21</version>
                                 </requireJavaVersion>
                             </rules>
                         </configuration>
@@ -174,7 +175,7 @@
             <extension>
                 <groupId>org.apache.maven.wagon</groupId>
                 <artifactId>wagon-webdav-jackrabbit</artifactId>
-                <version>2.10</version>
+                <version>3.5.3</version>
             </extension>
         </extensions>
 
diff --git a/pom.xml b/pom.xml
index 76dcac9..051affc 100644
--- a/pom.xml
+++ b/pom.xml
@@ -5,7 +5,7 @@
 
     <groupId>org.openconext</groupId>
     <artifactId>oidc-playground</artifactId>
-    <version>3.0.2-SNAPSHOT</version>
+    <version>4.0.0-SNAPSHOT</version>
     <packaging>pom</packaging>
 
     <name>oidc-playground</name>
@@ -14,13 +14,13 @@
     <parent>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-parent</artifactId>
-        <version>2.7.17</version>
+        <version>2.7.18</version>
         <relativePath/>
     </parent>
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <java.version>11</java.version>
+        <java.version>21</java.version>
     </properties>
 
     <modules>