diff --git a/.github/workflows/ruby.yml b/.github/workflows/ruby.yml
index ab63ece..4dcb837 100644
--- a/.github/workflows/ruby.yml
+++ b/.github/workflows/ruby.yml
@@ -14,7 +14,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-latest, macos-latest, windows-latest]
+        os: [ubuntu-latest, ubuntu-20.04, macos-latest, macos-13, macos-12, windows-latest, windows-2019]
         ruby: ['3.0.7', '3.1', '3.2', '3.3']
 
     steps:
diff --git a/Gemfile.lock b/Gemfile.lock
index 98ea807..a109df4 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -160,6 +160,7 @@ PLATFORMS
   x64-mingw-ucrt
   x64-mingw32
   x86_64-darwin-19
+  x86_64-darwin-20
   x86_64-darwin-21
   x86_64-linux