diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f49e880..5888c00 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -14,6 +14,7 @@ jobs:
       matrix:
         java-version:
           - 17
+          - 21
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-java@v2