How GitHub uses GitHub Actions and Actions larger runners to build and test GitHub.com

GitHub's Developer Experience (DX) team has transitioned their continuous integration (CI) system to GitHub Actions, leveraging the newly released larger runners to meet the scaling demands of their engineering team. This shift has improved the developer experience by allowing GitHub engineers to quickly and confidently ship software, using autoscaling capabilities and custom VM images to streamline the CI process. With the ability to run 15,000 CI jobs within an hour across 150,000 cores of compute, larger runners facilitate efficient scaling and management of CI workflows. GitHub Actions' features, such as reusable workflows and workflow outcome reusability, have further optimized the CI processes by reducing redundancy and improving efficiency. The DX team has also developed a remote access solution to securely connect larger runners to GitHub's private services, enhancing both security and accessibility. This comprehensive approach demonstrates GitHub's commitment to refining its CI infrastructure to support rapid development and deployment, ultimately enhancing the overall developer experience.