What is the difference between an API Gateway and a Service Mesh in microservices?

Short answer: API Gateway: An API Gateway acts as an entry point for client requests, routing them to the appropriate microservices.

Explain a bit more

It handles authentication, rate limiting, load balancing, and response aggregation. Example: An API Gateway could route a request for placing an order to both the Order Service and Payment Service. Service Mesh: A service mesh manages communication between microservices themselves. It provides service discovery, traffic management, security, and monitoring. Example: A service mesh like Istio helps microservices communicate securely and ensures traffic routing, retries, and circuit breaking without changing application code.

Real-world example (ShopNest)

ShopNest’s API Gateway routes /orders to the Order service and /payments to Payment—clients talk to one entry point.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.