diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5f87860d..205e79fe 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -10,7 +10,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: [3.0, 3.1, 3.2, 3.3, head, truffleruby-head]
+        ruby: ['3.0', 3.1, 3.2, 3.3, head, truffleruby-head]
     env:
       RAILS_ENV: test
     steps: