diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5dfe0ea..8ebe47f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -8,7 +8,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: [ ruby-head, '3.1', '3.0', '2.7', '2.6', '2.5' ]
+        ruby: [ ruby-head, '3.1', '3.0', '2.7', '2.6', '2.5', truffleruby-head ]
     steps:
       - name: Checkout
         uses: actions/checkout@v2