GitHub Availability Report: October 2021

In October, GitHub experienced a significant incident affecting the availability of the Codespaces service due to a core API response restructuring during a public API launch, which disrupted existing clients relying on a stable schema. The incident, occurring on October 8 and lasting 1 hour and 36 minutes, prevented new Codespaces from being initiated via the Visual Studio Code Desktop client, although connections to the web editor and existing sessions were only partially degraded. The issue was resolved after the regression was rolled back, restoring full functionality, but initial monitoring systems failed to detect the issue promptly, leading to a delayed response. To prevent similar problems, GitHub is enhancing its end-to-end testing tools and expanding monitoring to better reflect user experiences across service boundaries. The company commits to ongoing updates regarding efforts to ensure service reliability, as outlined in their engineering blog.