Actix-web Framework Guide

Applies to: Actix-web 4+, Rust Web APIs, High-Performance Services Complements: .claude/skills/rust-guide/SKILL.md

Core Principles

1. Type-Safe Extraction: Use extractors (web::Json, web::Path, web::Query) for request data
2. Thin Handlers: Handlers delegate to services; no business logic in handlers
3. Structured Errors: Implement ResponseError for all error types; never return raw strings
4. Shared State via web::Data: Application state is injected, never global
5. Middleware for Cross-Cutting: Auth, logging, CORS belong in middleware, not handlers

Project Structure