API Gateway Pattern

ELI5 — The Vibe Check

An API gateway is the front door for all your microservices. Instead of clients knowing about 20 different services, they talk to one gateway that routes requests to the right service. It also handles auth, rate limiting, and response aggregation. One door, many rooms.

Real Talk

The API gateway pattern provides a single entry point for client requests in a microservice architecture. It handles request routing, composition, authentication, rate limiting, protocol translation, and response aggregation. Popular implementations include Kong, AWS API Gateway, and custom gateways with Express/Fastify. Reduces client complexity and enables cross-cutting concerns.

When You'll Hear This

"The API gateway aggregates data from 3 microservices into one response." / "Put rate limiting and auth in the API gateway so individual services don't need it."