Between November 20, 2025 17:16 UTC to November, 2025 19:08 UTC some users experienced delayed or failed Git Operations for raw file downloads. On average, the error rate was less than 0.2%. This was due to a sustained increase in unauthenticated repository traffic.We mitigated the incident by applying regional rate limiting and are taking steps to improve our monitoring and time to mitigation for similar issues in the future.
On November 19, between 17:36 UTC and 18:04 UTC, GitHub Actions service experienced degraded performance that caused excessive latency in queueing and updating workflow runs and job statuses. Operations related to artifacts, cache, job steps and logs also had significantly increased latency. At peak, 67% of workflow jobs queued during that timeframe were impacted, and the median latency for impacted operations increased by up to 35x.This was caused by a significant change in load pattern on Actions Cache-related operations, leading to a saturated shared resource on the backend. The impact was mitigated by mitigating the new load pattern.To reduce the likelihood of a recurrence, we are improving rate-limiting measures in this area to ensure a more consistent experience for all customers. We are also evaluating changes to reduce the scope of impact.
This incident has been resolved. Thank you for your patience and understanding as we addressed this issue. A detailed root cause analysis will be shared as soon as it is available.
From Nov 18, 2025 20:30 UTC to Nov 18, 2025 21:34 UTC we experienced failures on all Git operations, including both SSH and HTTP Git client interactions, as well as raw file access. These failures also impacted products that rely on Git operations.The root cause was an expired TLS certificate used for internal service-to-service communication. We mitigated the incident by replacing the expired certificate and restarting impacted services. Once those services were restarted we saw a full recovery.We have updated our alerting to cover the expired certificate and are performing an audit of other certificates in this area to ensure they also have the proper alerting and automation before expiration. In parallel, we are accelerating efforts to eliminate our remaining manually managed certificates, ensuring all service-to-service communication is fully automated and aligned with modern security practices.
Between November 17, 2025 21:24 UTC and November 18, 2025 00:04 UTC the gists service was degraded and users were unable to create gists via the web UI. 100% of gist creation requests failed with a 404 response. This was due to a change in the web middleware that inadvertently triggered a routing error. We resolved the incident by rolling back the change. We are working on more effective monitoring to reduce the time it takes to detect similar issues and evaluating our testing approach for middleware functionality.
From Nov 17, 2025 00:00 UTC to Nov 17, 2025 15:00 UTC Dependabot was hitting a rate limit in GitHub Container Registry (GHCR) and was unable to complete about 57% of jobs.To mitigate the issue we lowered the rate at which Dependabot started jobs and increased the GHCR rate limit.We’re adding new monitors and alerts and looking into more ways to decrease load on GHCR to help prevent this in the future.
On November 4, 2025, GitHub Enterprise Importer experienced a period of degraded migration performance and elevated error rates between 18:04 UTC and 23:36 UTC. During this interval customers queueing and running migrations experienced prolonged queue times and slower processing.
The degradation was ultimately connected to higher than normal system load, once load was reduced error rates returned to normal. The investigation is ongoing to pinpoint the precise root cause and prevent future recurrence.
Long-term work is planned to strengthen system resilience under high load and promote better visibility into migration status for customers.
From Nov 13, 2025 14:50 UTC to Nov 13, 2025 15:01 UTC we experienced failures on all Git Push and SSH operations. An internal service became unhealthy due to a scaling configuration change. We reverted the change and are evaluating our health monitoring and processes to prevent similar incidents.
On November 12, 2025, between 22:10 UTC and 23:04 UTC, Codespaces used internally at GitHub were impacted. There was no impact to external customers. The scope of impact was not clear in the initial steps of incident response, so it was considered public until confirmed otherwise. One improvement from this will be improved clarity of internal versus public impact for similar failures to better inform our status decisions going forward.
On November 12th, 2025, from 13:10 - 17:40 UTC, notifications service was degraded, showing an increase in web notifications latency and increasing delays in notification deliveries. A change to the notifications settings access path introduced additional load to the settings system, degrading its response times. This impacted both requests to web notifications (with p99 response times as high as 1.5s, while lower percentiles remained stable) and notification deliveries, which reached a peak delay of 24 minutes on average. System capacity was increased around 15:10 UTC and the problematic change was fully reverted soon after that, restoring the latency of web notifications and increasing notification delivery throughput, decreasing the delay in notification deliveries. The notification queue was fully emptied around 17:40 UTC.We are working to adjust capacity in the affected systems and to improve the time needed to address these capacity issues.