diff --git a/.github/workflows/ruby.yml b/.github/workflows/ruby.yml
index aa6736a..cb955e6 100644
--- a/.github/workflows/ruby.yml
+++ b/.github/workflows/ruby.yml
@@ -34,5 +34,6 @@ jobs:
       with:
         ruby-version: ${{ matrix.ruby-version }}
         bundler-cache: true # runs 'bundle install' and caches installed gems automatically
+        bundler: 2.4.22 # For Ruby 2.7 compatibility
     - name: Run tests
       run: bundle exec rake