The Backend-for-Frontend (BFF) pattern is often introduced as a way to simplify systems, offering cleaner APIs, faster frontend development, and improved separation of concerns. On the surface, it works well. But in real-world systems, BFFs rarely remain simple for long.

Over time, they begin to absorb business logic, replicate backend complexity, and grow increasingly dependent on multiple downstream services. What starts as a lightweight orchestration layer gradually shifts into a critical dependency that is harder to evolve than it was meant to be.

In this talk, we’ll examine how BFFs unintentionally evolve into “mini-monoliths” through a series of small, pragmatic decisions, handling edge cases, bridging backend gaps, and centralizing logic for convenience. Drawing from real-world scenarios, we’ll explore the subtle tipping points where architectural boundaries begin to blur, and why these issues often remain invisible until they start impacting scalability, maintainability, and team velocity.