diff --git a/.github/workflows/spec.yml b/.github/workflows/spec.yml
index 19509fb..58b9fe0 100644
--- a/.github/workflows/spec.yml
+++ b/.github/workflows/spec.yml
@@ -14,7 +14,7 @@ jobs:
     strategy:
       matrix:
         os: ['ubuntu-20.04', 'ubuntu-22.04']
-        ruby-version: ['3.1', '3.2']
+        ruby-version: ['3.1', '3.2', '3.3']
         include:
         - os: 'ubuntu-20.04'
           ruby-version: '3.0'