diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8759caa..417004b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,7 +11,7 @@ jobs:
       matrix:
         ruby:
           - 2.7
-          - 3.0
+          - '3.0'
           - 3.1
           - 3.2
           - 3.3