Glossary

API Gateway

An API gateway is a server that acts as a single entry point for a collection of microservices. It manages, routes, and secures incoming requests from clients, translating them into the appropriate backend service calls while handling cross-cutting concerns such as authentication, rate limiting, and request transformation.

In modern software architectures, applications are increasingly composed of distributed services rather than a single monolithic codebase. As the number of these services grows, managing direct client communication becomes complex and inefficient. An API gateway simplifies this by decoupling the client from the backend infrastructure. It provides a unified interface that abstracts internal service complexity, allowing developers to scale, update, or replace individual components without requiring changes to the client-side implementation or exposing internal network topology.

When implementing an API gateway, practitioners must configure routing rules to direct traffic to specific endpoints based on request paths or headers. It serves as a centralized control plane for enforcing security policies, such as JWT validation or OAuth, and managing traffic flow through throttling and load balancing. Developers should monitor the gateway for latency bottlenecks, as it represents a critical path in the request lifecycle. Proper configuration ensures that the gateway remains a facilitator of communication rather than a single point of failure.

Last updated: 2026-08-26