diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index ab49c7932..e55a67a7b 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -12,10 +12,11 @@ jobs:
       matrix:
         # ubuntu-22.04 uses OpenSSL 3.0, ubuntu-20.04 uses OpenSSL 1.1.1
         os: [ ubuntu-22.04, ubuntu-20.04, macos-latest, windows-latest ]
-        ruby: [ head, "3.1", "3.0", "2.7", "2.6" ]
+        ruby: [ head, "3.1", "3.0", "2.7", "2.6", truffleruby-head ]
         exclude:
           # uses non-standard MSYS2 OpenSSL 3 package
           - { os: windows-latest, ruby: head }
+          - { os: windows-latest, ruby: truffleruby-head }
         include:
           - { os: windows-latest, ruby: ucrt }
           - { os: windows-latest, ruby: mswin }