How PlanetScale makes schema changes

This post details PlanetScale's internal workflow for making schema changes, which leverages their own online schema change tooling built on Vitess. It highlights the separation of schema changes from code deployments, the use of a GitHub Actions bot to automate branch creation and deploy requests, and the importance of the expand-migrate-contract pattern for backward compatibility. The post also emphasizes the queuing mechanism for concurrent schema changes and the safety checks performed by PlanetScale.