diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index f8118c2..e8343fa 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -7,7 +7,7 @@ jobs:
     name: build (${{ matrix.ruby }} / ${{ matrix.os }})
     strategy:
       matrix:
-        ruby: [ head, '3.1', '3.0', '2.7', '2.6' ]
+        ruby: [ head, '3.3', '3.2', '3.1', '3.0', '2.7', '2.6' ]
         os: [ ubuntu-latest, macos-latest ]
     runs-on: ${{ matrix.os }}
     steps: