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Problem Understanding
Restate the problem in your own words.
Design an API Gateway
Design an API Gateway: a single edge entry point that fronts dozens to thousands of microservices, handles TLS, auth, rate-limiting, request routing, header rewriting, response caching, and circuit-breaking, then forwards the request to the right backend. The hard parts are the routing table at scale (without a redeploy per change), latency overhead under tens of thousands of routes, and graceful degradation when one backend goes hot — the gateway must shed load without taking down the rest of the platform.
- AWS API GatewayManaged gateway — routes to Lambda / VPC / HTTP backends. Pay-per-request, hot path is built-in CDN.
- KongOSS Lua-based gateway on Nginx — hugely extensible plugin model, popular self-hosted.
- Envoy + IstioService-mesh era — each pod has a sidecar Envoy; the gateway is just one with public-facing rules.
- Netflix ZuulThe Java reference design that popularised the pattern; Zuul 2 added async I/O.
Your task: read the problem above, then write what the system is, who uses it, the rough scale, and the headline UX expectation — in your own words. Submit for AI review when you're ready.
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