diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index e4c80e7..8fe6b4a 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -6,7 +6,7 @@ jobs:
   test:
     strategy:
       matrix:
-        ruby: [ 3.0, 2.7, 2.6, 2.5, 2.4, head ]
+        ruby: [ '3.0', 2.7, 2.6, 2.5, 2.4, head ]
         os: [ubuntu-latest, macos-latest, windows-latest]
     runs-on: ${{ matrix.os }}
     steps: