Backend API

RESTful API design uses resource-based URL structures with appropriate HTTP methods (GET, POST, PUT, PATCH, DELETE) and standard status codes. Structure endpoints around nouns (e.g., /users, /products) and map operations to HTTP verbs for predictable, maintainable APIs that clients can easily consume.

HTTP status codes signal the outcome of API requests: 2xx for success, 4xx for client errors, 5xx for server errors. Using correct codes (200 OK, 201 Created, 400 Bad Request, 404 Not Found, 500 Internal Server Error) ensures predictable behavior and helps clients handle responses consistently.

API versioning strategies include URL paths (/v1/users), request headers, or query parameters. Versioning lets you evolve endpoints gracefully, add features, and deprecate old behavior while maintaining backward compatibility for existing integrations and clients.

REST uses standard HTTP methods and status codes with resource-based URLs, making APIs predictable and cacheable. REST principles prioritize statelessness, standard conventions, and clarity, distinguishing it from other approaches like RPC or GraphQL that use different patterns.

API documentation is essential for adoption. OpenAPI/Swagger specifications provide machine-readable, standardized formats that generate interactive docs, SDKs, and reduce integration friction. Documentation should describe endpoints, request bodies, response formats, status codes, and usage examples.

Yes. Middleware handles cross-cutting concerns like authentication, rate limiting, and logging before requests reach endpoints. Rate limiting protects APIs from overuse, middleware components process requests consistently, and both integrate into REST architectures for security and performance.