diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index d3e4ec0..0e36f68 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -12,7 +12,7 @@ jobs:
 
     strategy:
       matrix:
-        ruby: [ '2.3', '2.4', '2.5', '2.6', '2.7', '3.0', '3.1', '3.2', 'ruby-head' ]
+        ruby: [ '2.3', '2.4', '2.5', '2.6', '2.7', '3.0', '3.1', '3.2', '3.3', 'ruby-head' ]
 
     steps:
       - uses: actions/checkout@v4