GitHub's July postmortem: 96% peak error rate on July 8, an expired SSL cert breaking runners, and 113,930 failed PR creations
GitHub's August 13 availability report details eight July 2026 incidents. The worst was July 8 (7h 4m) where an automated infrastructure process changed runtime configuration and broke service discovery, peaking at ~96% error rate across Web UI, REST/GraphQL APIs, Actions, Packages, Copilot, and Git operations. Others: a July 19 SSL certificate expiration delayed 9% of Actions runs (peaking 21.4%), a Vitess vschema change deleted a backing table and broke 113,930 pull request creation attempts across 50,904 users in 57 minutes, and Redis cluster maintenance on July 25 failed 60% of Actions runs at peak. The MCP Server's web_search tool also hit a 42% average error rate for three hours from upstream provider degradation.
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