What is the BFF Pattern?

The Backends-for-Frontends (BFF) pattern involves creating dedicated API gateways for each client type (web, mobile, partner APIs). Each BFF acts as a specialized intermediary that handles client-specific concerns like rate limiting, authentication, caching, and header sanitization. Key advantages include improved resiliency through isolation, client-specific optimization, and faster development velocity. Drawbacks include potential code duplication, growing complexity, and BFF proliferation. Best practices recommend clearly defining client requirements, extracting shared logic into libraries, maintaining clear boundaries, and monitoring performance.