diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a8d8b71..cab8a0e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -33,7 +33,7 @@ jobs:
       - if: runner.os != 'Windows'
         uses: ruby/setup-ruby@v1
         with:
-          ruby-version: "4.0"
+          ruby-version: "4.0.5"
       - run: go version
       - run: go vet ./...
       - run: go build ./...