API Gateway Pattern

A single entry point routes, authenticates, rate-limits, and protects backend services.

gateway

Detailed Description

Gateways are edge infrastructure. They protect internal services from client-specific routing, authentication, throttling, and protocol concerns.

Keep business logic out of the gateway so it does not become a second monolith.

Client -> API Gateway
-> auth
-> rate limit
-> route to service

Pros

Centralizes cross-cutting concerns, hides topology

Cons

Can become bottleneck or single point of failure

Examples: Kong, AWS API Gateway, Nginx, Traefik