diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 90894cfa..a8b206b4 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -21,6 +21,7 @@ jobs:
           - { os: windows-latest, ruby: ucrt }
           - { os: windows-latest, ruby: mingw }
           - { os: windows-latest, ruby: mswin }
+          - { os: macos-13, ruby: 2.5 }
         exclude:
           # CRuby < 2.6 does not support macos-arm64
           - { os: macos-latest, ruby: 2.5 }
@@ -33,6 +34,10 @@ jobs:
           apt-get: "haveged libyaml-dev"
           brew: libyaml
           vcpkg: libyaml
+      - name: Set JRuby ENV vars
+        run: |
+          echo 'JAVA_OPTS=-Xmx1g' >> $GITHUB_ENV
+        if: ${{ ! startsWith(matrix.ruby, 'jruby') }}
       - name: Install dependencies
         run: bundle install --jobs 1
       - name: Run test