How I Structure Node.js Backends for Freelance and Startup Projects

Goals

For client and startup work, backend code needs to be:

• Easy to onboard new devs
• Simple to deploy
• Easy to extend

My Usual Layout

• `src/config` — env, DB, logging
• `src/modules` — one folder per domain (auth, users, orders…)
• `src/modules/*/controller.ts`
• `src/modules/*/service.ts`
• `src/modules/*/model.ts` (or Prisma schema)
• `src/routes` — wiring routes to controllers

Other Conventions

• All responses go through a small helper (consistent shape)
• Error classes for domain vs validation vs auth errors
• Request validation with Zod or Joi, never “trust the client”

This keeps things boring in a good way — and boring backends scale.