API Versioning and Deprecation

API versioning strategies impact security by determining how long vulnerable versions remain accessible. URL versioning (/api/v1/, /api/v2/) provides clear separation but complicates routing. Header versioning keeps URLs clean but requires client awareness. Backward compatibility pressures often lead to maintaining insecure legacy endpoints.

Deprecation processes must balance security needs with client migration timelines. Clear communication about deprecation schedules, migration guides, and breaking changes helps clients update before support ends. Monitoring deprecated endpoint usage identifies clients requiring additional support. Forced deprecation of vulnerable endpoints may be necessary despite client impact.