API Versioning & Evolution Framework

API versioning fails when it's reactive — adding versions only when a breaking change has already been made and consumers are complaining. A version strategy must be designed before the first consumer integrates, because the version strategy determines how changes are communicated, how long old versions are supported, and what mechanism consumers use to access the specific version they've built against.

The API Versioning Framework distinguishes breaking from non-breaking changes, establishes the deprecation lifecycle that protects existing integrations, and provides migration tooling that makes version upgrades tractable.