Building Resilient REST APIs

Creating an API is easy, but building one that survives edge cases, traffic spikes, and bad data requires defensive engineering.

• Rate Limiting: Never trust the client. Implement strict rate limiting at the edge to protect your backend infrastructure from DDoS attacks or accidental infinite loops on the frontend.
• Idempotency: Designing your POST and PUT requests to be idempotent guarantees that if a client accidentally sends the same payment or creation request twice due to network lag, the backend only processes it once.
• Graceful Degradation: If a third-party microservice your API relies on goes down, your entire API shouldn’t crash. Use timeouts, circuit breakers, and fallback cache layers to keep the core system running.