Nodejs Backend Typescript

This covers the practical patterns you need for building type-safe Node.js backends: Express and Fastify server setup, request validation with Zod and TypeBox, middleware patterns for auth and error handling, and proper TypeScript configuration with strict mode. The examples show real implementations like extending Express Request types, building reusable validation middleware, and using Fastify's plugin system with decorators. It's opinionated toward modern tooling (tsx for dev, native ESM) and treats type safety as non-negotiable rather than optional. If you're moving a JavaScript backend to TypeScript or starting fresh with either framework, the routing and middleware patterns here are copy-paste ready and follow current best practices.