macOS Big Sur, or 11.0, is now available in preview for GitHub Actions. Try it by setting runs-on: macos-11.0 in your workflow file.

Screenshot of run using macOS 11

The MacOS 11.0 Big Sur virtual environment has different tools and tool versions than MacOS 10.15 Catalina. See the full list of changed software.

If you see any issues with your workflows when using Big Sur create an issue in the virtual-environments repository.