Partial degradation for code scanning default setup and for code quality

Lesson: Teams should incorporate automation and AI into DevSecOps workflows to build highly available services and address security challenges across the software lifecycle.

What happened

On April 20, 2026 between 10:28 UTC and 15:04 UTC GitHub experienced degraded service for code scanning default setup, code quality, and project boards. Repair of affected project boards additionally lasted until April 21, 05:04 UTC During this time, code scanning default setup and code quality analyses were not triggered on newly opened pull requests. Additionally, newly created issues were not appearing on project boards. The cause was a serialization error that prevented proper triggering of code scanning, code quality analyses, and project board updates. We mitigated the issue by deploying a fix, restoring event publishing for code scanning and code quality. For project boards, an additional code change was deployed to update event consumers, followed by a reindex of affected project items. We are working to prevent recurrence by strengthening our schema validations and improving monitoring for drops in publishing on critical hydro topics.

1. Resolved · Apr 21, 05:04 UTC
   On April 20, 2026 between 10:28 UTC and 15:04 UTC GitHub experienced degraded service for code scanning default setup, code quality, and project boards. Repair of affected project boards additionally lasted until April 21, 05:04 UTC During this time, code scanning default setup and code quality analyses were not triggered on newly opened pull requests. Additionally, newly created issues were not appearing on project boards. The cause was a serialization error that prevented proper triggering of code scanning, code quality analyses, and project board updates. We mitigated the issue by deploying a fix, restoring event publishing for code scanning and code quality. For project boards, an additional code change was deployed to update event consumers, followed by a reindex of affected project items. We are working to prevent recurrence by strengthening our schema validations and improving monitoring for drops in publishing on critical hydro topics.