diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 7ddcb414..ffe43694 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,7 +13,11 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        java: [7, 8, 11]
+        java:
+          - 7
+          - 8
+          - 11
+          - 21
 
     steps:
       - name: Checkout repository