1.4.1 API Versioning
Versioning is how you evolve /v1/orders to /v2/orders or add fields without surprising old apps.
Why it matters
Mobile apps and partner integrations cannot deploy the same day you do. A breaking change without a version strands them.
How it is used
Prefer additive changes (new optional fields) over a new version. When you must break, keep v1 running with a sunset date. Put the version in the path or a header — pick one and document it.