expresslisted

# Express Skill ## When to activate - Building a REST API with Express.js - Adding middleware (auth, validation, CORS, rate limiting) to an Express app - Setting up project structure and error handling for a production Express service - Migrating from callbacks to async/await in Express handlers - Adding request validation and typed routes to an Express app ## When NOT to use - Edge deployments — use the hono skill (Cloudflare Workers) - Full-stack framework — use the nextjs skill - High-throughput microservices needing raw performance — consider Fastify ## Instructions ### Project setup and structure ``` Set up a production-ready Express.js project. Language: [TypeScript (recommended) / JavaScript] Database: [PostgreSQL / MongoDB / none] Auth: [JWT / session / none] Directory structure: src/ app.ts ← Express app setup (no listen here) server.ts ← entry point (listen + graceful shutdown) routes/ index.ts ← router aggregator users.ts ← users routes auth.ts ← auth routes middleware/ auth.ts ← JWT verification middleware validate.ts ← Zod validation middleware errorHandler.ts← global error handler controllers/ users.ts ← business logic services/ db.ts ← database connection types/ index.ts ← shared types and error classes // src/app.ts import express from 'express' import cors from 'cors' import helmet from 'helmet' import { rateLimit } from 'express-rate-l