diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index abea6695..abff2918 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -16,7 +16,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: [ '3.1', '3.4' ]
+        ruby: [ '3.1', '3.2', '3.3', '3.4' ]
     name: Test with Ruby ${{ matrix.ruby }}
     steps:
       - uses: actions/checkout@v6