version-api

Implements REST API versioning strategies for Rails APIs with hard security gates. Use when the user asks about API versioning, adding a new API version (v1/v2), deprecating API endpoints, maintaining backward compatibility in REST APIs, versioned API routes, versioned endpoints, Rails API versioning, or API version management. Generated controller code MUST sanitize all caller-supplied input (version identifiers, Accept headers) — never constantize or evaluate untrusted values. Maintains backward compatibility by inheriting new version controllers from the previous version's controller, overriding only changed actions, and runs compatibility specs via bundle exec rspec spec/requests/api/backward_compatibility_spec.rb to confirm no regressions before merging. REST API versioning, URL path versioning, Deprecation headers, versioned API routes, Rails API versioning, v1/v2 endpoints, API version management.