GitHub Availability Dips in June 2026

GitHub's June 2026 availability report reveals a mixed bag of progress and setbacks, detailing six incidents that degraded service performance. The company is doubling down on transparency, as noted in the monthly report, responding to customer demand for more insight into infrastructure investments.

The push to migrate traffic from the monolithic architecture saw Monolith traffic in Azure Central US peak at 45%, falling short of projections due to a stability incident on May 21. The ramp-up was paused for nearly a month and restarted with stricter stability gates.

Git in Azure reached a peak of 43% traffic, missing the 50% target. This plateau is attributed to decisions aimed at avoiding user latency, specifically awaiting additional vPoP traffic and currently routing only HTTP traffic for Git.

Architectural Milestones Amidst Challenges

Despite missed targets, significant progress was made. The new extracted pull requests service, pullsd, now handles 100% of anonymous pull request reads. Reposd, an extracted repository service, became the first to serve production REST traffic from Azure, reaching 50% before being scaled back due to a Redis capacity constraint.

A new users service is offloading approximately 500,000 queries per second from the primary database. API rate limiting is now largely handled at the Gateway, reducing contention within the monolith.

Client-side database load shedding is live against 5% of production traffic, providing crucial data for managing stress. Furthermore, two-person confirmation is now mandated for interactive production access and ChatOps changes, enhancing security with a unified audit trail.

June Incidents

The report details two primary incidents from June 2026:

• On June 4, Copilot code review experienced elevated failures, with an average of 81.6% of requests failing due to an incompatible dependency release. Mitigation involved removing the problematic version and redeploying the service. Future prevention includes dependency pinning and improved compatibility checks. This incident underscores the importance of robust error handling, even for advanced tools like GitHub Copilot.
• On June 8, signed-out users faced sustained HTTP 504 errors on various GitHub pages due to a surge in abusive, automated anonymous traffic. The issue impacted unauthenticated requests, causing gateway timeouts. Mitigation involved targeted blocking of anomalous traffic patterns.

GitHub continues to prioritize availability, capacity, and then features.