diff --git a/.github/workflows/benchmark.yml b/.github/workflows/benchmark.yml
index b83f5b0a3e0..5ab55bcee13 100644
--- a/.github/workflows/benchmark.yml
+++ b/.github/workflows/benchmark.yml
@@ -25,7 +25,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: [2.7, '3.0', 3.1, 3.2, 3.3, 3.4, jruby-9.4]
+        ruby: [2.7, '3.0', 3.1, 3.2, 3.3, 3.4, '4.0', jruby-9.4]
 
     steps:
       - name: Setup Ruby
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 251958aeeab..18d3813a1b3 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -49,7 +49,7 @@ jobs:
       matrix:
         # Supported ruby versions
         # Jruby 10 is expected to fail until fix is live: https://github.com/jruby/jruby/issues/8847
-        ruby: [2.7, '3.0', 3.1, 3.2, 3.3, 3.4, jruby-9.4, jruby-10.0]
+        ruby: [2.7, '3.0', 3.1, 3.2, 3.3, 3.4, '4.0', jruby-9.4, jruby-10.0]
         env: [KITCHEN_SINK, CRT]
 
         exclude: