diff --git a/.github/workflows/scala.yml b/.github/workflows/scala.yml
index 4043c55..f4fa8fb 100644
--- a/.github/workflows/scala.yml
+++ b/.github/workflows/scala.yml
@@ -12,7 +12,7 @@ jobs:
     strategy:
       matrix:
         # test against latest update of each major Java version, as well as specific updates of LTS versions:
-        java: [ 8, 11 ]
+        java: [ 8, 11, 21 ]
     name: Java ${{ matrix.java }}
     steps:
     - uses: actions/checkout@v2