API Versioning Core Principles 1. Version from day one — Adding versioning later is painful. Start with a version in the URL even if you only have v1. 2. URL segment versioning is the default — is the most discoverable and cache-friendly strategy. 3. Never break existing versions — Add a new version for breaking changes. Deprecate the old version with a timeline. 4. Version the API, not individual endpoints — All endpoints in a version group share the same version number. Patterns Setup with Asp.Versioning URL Segment Versioning (Recommended) Header Versioning (Alternative) Deprecating a Vers…