diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a35639b..9aa5a37 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -20,7 +20,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: ["2.7", "3.0", "3.1", "3.2", "head"]
+        ruby: ["2.7", "3.0", "3.1", "3.2", "3.3", "head"]
     steps:
       - uses: actions/checkout@v3
       - run: rm Gemfile.lock