# Incident with pull requests

DevFeed: [Incident with pull requests](<https://devfeed.tech/articles/incident-with-pull-requests-76029.md>)

Original publisher: [Read original article](<https://www.githubstatus.com/incidents/6swp0zf7lk8h>)

Published: 2025-08-05T15:42:00Z

Content type: news

Language: en

Sources: [GitHub Status - Incident History](<https://devfeed.tech/sources/github-status-incident-history.md>)

Topics: [Tech Debt](<https://devfeed.tech/topics/tech-debt.md>), [Automation](<https://devfeed.tech/topics/automation.md>), [read-replica](<https://devfeed.tech/topics/read-replica.md>), [Continuous Deployment (CD)](<https://devfeed.tech/topics/continuous-deployment.md>)

Tags: [automation](<https://devfeed.tech/tags/automation.md>), [database](<https://devfeed.tech/tags/database.md>), [database-migration](<https://devfeed.tech/tags/database-migration.md>), [error](<https://devfeed.tech/tags/error.md>), [incident](<https://devfeed.tech/tags/incident.md>), [monitoring](<https://devfeed.tech/tags/monitoring.md>), [production](<https://devfeed.tech/tags/production.md>), [pull-request](<https://devfeed.tech/tags/pull-request.md>), [rest](<https://devfeed.tech/tags/rest.md>), [webhooks](<https://devfeed.tech/tags/webhooks.md>)

## AI overview

A production database migration dropped a column still referenced by the ORM in some pull request queries, causing elevated errors across GitHub services. A mitigation reduced the impact, but a fix that did not reach some custom and canary environments caused a smaller secondary incident. GitHub identified monitoring and cross-environment rollout gaps and plans additional automation and safeguards.

## Source excerpt

At 15:33 UTC on August 5, 2025, we initiated a production database migration to drop a column from a table backing pull request functionality. While the column was no longer in direct use, our ORM continued to reference the dropped column in a subset of pull request queries. As a result, there were elevated error rates across pushes, webhooks, notifications, and pull requests with impact peaking at approximately 4% of all web and REST API traffic. We mitigated the issue by deploying a change that instructed the ORM to ignore the removed column. Most affected services recovered by 16:13 UTC. However, that fix was applied only to our largest production environment. An update to some of our custom and canary environments did not pick up the fix and this triggered a secondary incident affecting ~0.1% of pull request traffic, which was fully resolved by 19:45 UTC. While migrations have protections such as progressive roll-out first targeting validation environments and acknowledge gates, this incident identified an application monitoring gap that would have prevented continued rollout when impact was observed. We will add additional automation and safeguards to prevent future incidents without requiring human intervention. We are also already working on a way to streamline some types of changes across environments, which would have prevented the second incident from occurring.