diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 7fc000e8..751894be 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -33,6 +33,7 @@ jobs:
         uses: ruby/setup-ruby@v1
         with:
           ruby-version: ${{ matrix.ruby }}
+          bundler: ${{ matrix.ruby == 'head' && 'default' || 'Gemfile.lock' }}
           bundler-cache: true
 
       - name: Run tests