Incident History

This incident was used to notify for a maintenance event. There is no specific root cause analysis. Work progressed as planned without any issues to report.

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.

On June 23, 2026, between 22:45 and 23:29 UTC, GitHub Copilot Completions and Next Edit Suggestions were degraded for users in all regions. During this window, affected users may have seen failed or missing code completions and Next Edit Suggestions. On average about 25% of Completions and Next Edit Suggestions requests failed during the impact window, peaking at roughly 27%. The cause was a configuration change that prevented the Copilot service from obtaining the authentication tokens it needs to reach its model backends; this both failed requests directly and caused the service to temporarily remove backends from rotation. GitHub engineers detected the elevated error rate within minutes, declared an incident, and mitigated the issue at 23:22 UTC by redeploying the service with a known-good configuration, which restored normal operation. As a follow-up, the team disabled the affected authentication path to prevent a future deployment from re-introducing the problem, and is making the change rollout safer. We apologize for the disruption and are taking steps to reduce the likelihood of similar incidents.

On June 17, 2026, between 11:35 UTC and 19:20 UTC, the Webhooks service was degraded and delivered webhook payloads with missing installation information. On average, 11.3% of webhook deliveries were impacted. Customers relying on the installation field for authentication or routing were unable to process affected webhooks. A smaller subset of deliveries for the security_advisory event (0.04%) were delivered successfully but were not recorded for redelivery. This was due to a defect in a new delivery code path that failed to include installation data in webhook payloads.

We mitigated the incident by disabling the feature flag controlling the new code path.

We are working to improve our automated validation of webhook payloads, and introduce automated alerting for webhook payload regressions to reduce our time to detection and mitigation of issues like this one in the future.

The following events were affected: branch_protection_configuration, code_scanning_alert, commit_comment, custom_property, custom_property_values, dependabot_alert, deploy_key, deployment_protection_rule, deployment_review, dismissal_request_code_scanning, dismissal_request_secret_scanning, installation_target, member, membership, merge_queue_entry, org_block, organization, projects_v2, projects_v2_item, pull_request_review_thread, repository_ruleset, secret_scanning_alert, secret_scanning_alert_location, secret_scanning_scan, security_and_analysis, star, sub_issues, team, team_add, workflow_job.

On June 17, 2026, between 16:57 UTC and 19:14 UTC, Copilot code completions were degraded and users were unable to receive Next Edit Suggestions. Standard ghost text code completions were not affected. This was due to a configuration change that caused the service's routing layer to incorrectly discard all Next Edit Suggestion model endpoints as invalid.We mitigated the incident by deploying a corrected configuration change at 18:55 UTC, with full recovery observed at 19:14 UTC.We are working to improve the resilience of our routing layer to limit impact due to a subset of invalid configurations, and to improve our alerting to detect sudden traffic changes that are not captured by standard error rate monitors.

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.

On June 16, 2026, between 17:20 UTC and 18:15 UTC, the Opus 4.8 model experienced degraded availability in GitHub Copilot. During this window, some requests to Opus 4.8 failed or errored. Other Copilot models were not affected and remained available as alternatives. This was caused by an issue with an upstream model provider. The upstream provider resolved the issue, and we monitored Opus 4.8 until success rates returned to normal. The incident is fully resolved.

Between 17:38 UTC and 18:22 UTC on June 15, 2026, approximately 83% of requests to the analytics endpoint serving the /chronicle feature failed.  The cause was an internal feature-flag service that encountered a transient error and failed to recover, causing feature flag checks to fail. The analytics endpoint was gated behind one of these flags, resulting in requests being rejected. We restored service health by removing the feature flag gating the analytics endpoint and deploying that change. To avoid recurrence of similar incidents, we have changed the feature-flag client so that errors that are not known to be permanent are retried, and we are improving alerting and startup behavior so this class of failure is detected and recovered from faster.

On June 15, 2026, between 15:27 UTC and 16:23 UTC, GitHub webhook deliveries were delayed. During this window, webhook events were delivered later than normal, with average end-to-end delivery latency peaking at approximately 8.8 minutes. No webhook deliveries were lost — delayed events were queued and delivered once processing recovered.This was caused by a temporary throughput constraint in an internal event-processing system that moves webhook events through GitHub's delivery pipeline. The rate at which events were processed for delivery dropped below the incoming volume, creating a backlog. We restarted the affected pipeline service, after which throughput recovered and the backlog fully drained by approximately 16:29 UTC. Webhook delivery latency returned to normal, the incident was mitigated at 16:39 UTC, and fully resolved at 17:37 UTC.To reduce the likelihood and impact of similar incidents, we are working on improving the accuracy of the utilization metrics used to scale our delivery worker pools, reviewing connection and capacity headroom in the delivery pipeline.

On June 11, 2026, between 19:28 UTC and 21:06 UTC, GitHub webhook deliveries were delayed. Average delivery latency peaked at approximately 3.4 minutes, with some deliveries delayed by as much as 62 minutes at the 99th percentile. No events were lost — delayed events were queued and delivered once processing caught up.This was due to a change in how webhook traffic was distributed across regions: to relieve load on one region, a portion of processing was shifted to another, where higher latency prevented our delivery workers from keeping pace with incoming volume, creating a backlog. We mitigated the incident by rebalancing webhook traffic distribution; as load returned to normal levels, processing caught up and the delivery backlog fully drained.We are working on improving the accuracy of the utilization metrics used to scale our delivery worker pools, and reassess how we distribute webhook traffic across regions, to reduce our time to detection and mitigation of issues like this one in the future.