diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
index e8a792f..33eabb4 100644
--- a/.github/workflows/maven.yml
+++ b/.github/workflows/maven.yml
@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        jdk: [ 11, 17 ]
+        jdk: [ 17, 21 ]
 
     steps:
     - uses: actions/checkout@v4
diff --git a/pom.xml b/pom.xml
index 978074e..6164d24 100644
--- a/pom.xml
+++ b/pom.xml
@@ -11,8 +11,8 @@
     <url>https://github.com/t1/problem-details</url>
 
     <properties>
-        <maven.compiler.source>11</maven.compiler.source>
-        <maven.compiler.target>11</maven.compiler.target>
+        <maven.compiler.source>17</maven.compiler.source>
+        <maven.compiler.target>17</maven.compiler.target>
         <project.build.sourceEncoding>utf-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>utf-8</project.reporting.outputEncoding>