What is a Schema Registry and how does it assist CI/CD?

A Schema Registry is a central repository (like Apollo Studio) that stores versions of your GraphQL schema and tracks field usage.

In CI/CD, before a PR is merged, it runs a 'schema check' against the registry. The registry compares the proposed schema changes against production traffic patterns. If the PR removes a field that active clients are still querying, the CI fails to prevent an outage.