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What are some best practices for structuring a Node.js project?

Q: What are some best practices for structuring a Node.js project?

**TL;DR.** Organize by **feature/domain**, separate **layers** (routes/controllers → services → data access), keep **config in the environment**, centralize **error handling**, and isolate the **app** from the **server** (for testing). Favor small modules with single responsibilities over one giant file. routes / controllers (HTTP) services (business logic) <text class='d-text' x='23

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best practicesproject structurearchitecturemaintainability

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App separated from server

// app.js — wiring only, exported for tests
export const app = express();
app.use('/users', usersRouter);          // routes → services → repos
app.use(errorHandler);                    // centralized errors

// server.js — the only place that binds a port
import { app } from './app.js';
app.listen(process.env.PORT ?? 3000);
// tests:  request(app).get('/users')  — no real network needed

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