Incidentsby GlyphDisruption with some GitHub services
Dec 8, 21:28 UTCDec 8, 22:33 UTC
Duration
1h 5m
Impact
Minor
Root cause
Config change
GitHub, 90 days
69 incidents
Affected
Not listed by the vendor.
Final update
On December 8, 2025, between 21:15 and 22:24 UTC, Copilot code completions experienced a significant service degradation. During this period, up to 65% of code completion requests failed. The root cause was an internal feature flag that caused the primary model supporting Copilot code completions to appear unavailable to the backend service. The issue was resolved once the flag was disabled. To prevent recurrence, we expanded test coverage for Copilot code completion models and are strengthening our detection mechanisms to better identify and respond to traffic anomalies.
Timeline
- Resolved · Dec 8, 22:33 UTC
On December 8, 2025, between 21:15 and 22:24 UTC, Copilot code completions experienced a significant service degradation. During this period, up to 65% of code completion requests failed. The root cause was an internal feature flag that caused the primary model supporting Copilot code completions to appear unavailable to the backend service. The issue was resolved once the flag was disabled. To prevent recurrence, we expanded test coverage for Copilot code completion models and are strengthening our detection mechanisms to better identify and respond to traffic anomalies.