diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 54f7c58..84b99c1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        ruby: ["3.1", "3.2", "3.3"]
+        ruby: ["3.2", "3.3", "3.4", "4.0"]
     steps:
       - uses: actions/checkout@v2
       - uses: ruby/setup-ruby@v1