GitHub, the Microsoft-owned code-sharing platform with 225 million users, was down for more than three hours Monday morning, disrupting software development work around the world.
The issue started at 6:40 a.m. Pacific. Within an hour and a half, nearly every part of the service was broken or slowed, including the GitHub website, tools for reviewing and merging code, the automated systems that test and ship software, and the GitHub Copilot AI coding assistant.
GitHub said on its status page that it found the source of the problem shortly after 9:30 a.m. and by 10 a.m. had the outage under control, with services recovering. Copilot remained listed as an active incident and GitHub said it was still monitoring things overall for stability.
UPDATE, 2:45 p.m.: GitHub declared the outage resolved at 2:15 p.m., about seven and a half hours after it began. The company said it found the source of the problem Monday morning but kept working through the afternoon on scattered login failures that were still affecting Copilot and other services. GitHub said it will share a detailed explanation of what went wrong once it has one.
GitHub has been struggling for many months with the surge of AI-driven coding. GitHub CTO Vladimir Fedorov wrote in April that the company set out last fall to expand its capacity tenfold, then concluded by February that it needed to build for 30 times its current scale.
In June, a Microsoft spokesperson told Business Insider that the spike in AI agent development had tested GitHub’s infrastructure limits, and said the company was accelerating GitHub’s move onto Azure while pursuing a multi-cloud strategy. BI reported that the strategy includes renting capacity from Amazon Web Services, Microsoft’s biggest cloud rival.
UPDATE, Wednesday Aug. 19: In a post mortem on the incident, GitHub said a jump in traffic overwhelmed networking equipment at one of its U.S. data centers, and a setting meant to add capacity automatically failed to kick in.
The failure spread until it broke GitHub’s login system. Recovery dragged on because a bug in Microsoft’s Visual Studio Code editor sent 10 times the normal traffic to the service that logs users into Copilot, keeping the AI assistant down for hours after the rest of GitHub came back.
