diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e496f1a..8440d22 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -17,7 +17,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: [2.5, 2.6, 2.7, 3.0, 3.1]
+        ruby: ["2.7", "3.0", "3.1"]
     runs-on: ubuntu-latest
     steps:
     - name: Checkout repository