2025 Node.js Best Practices: ES Modules, Native fetch, Vitest, Bun & More

Node.js has long been a powerful tool for backend JavaScript applications, but by 2025 the way you write Node apps has changed dramatically. Continuing to use outdated methods can slow development efficiency.

1. Prefer ES Modules (ESM)

In 2025, ES modules are not only supported but are the default choice.

Why it matters

ESM works better with modern JavaScript tooling, supports top-level await, and aligns Node’s module system with browsers, so you can replace require with import.

Best practices

Use the .mjs extension or set "type": "module" in package.json.

Prefer import / export over require / module.exports.

Use top-level await to simplify asynchronous startup code.

// app.mjs
import { express } from 'express';
const app = express();
app.use("/", (req, res) => {
  res.send("Hello World");
});

2. Native fetch API

Node.js now includes the same fetch() functionality as browsers.

Why it matters

No longer need to install node-fetch; the global fetch() is standards‑compliant.

Best practices

Use fetch() for HTTP requests unless low‑level control is required.

Combine with AbortController for timeouts and cancellations.

const controller = new AbortController();
setTimeout(() => controller.abort(), 5000);
try {
  const res = await fetch('https://api.fakeapiexample.com/data', { signal: controller.signal });
  const data = await res.json();
  console.log(data);
} catch (err) {
  console.error('Request failed:', err);
}

3. Use Vitest for modern testing

While Jest is still used, Vitest has become the favorite for modern JavaScript and TypeScript developers.

Why it matters

Vitest is fast, has built‑in ESM support, integrates well with Vite, and works seamlessly with TypeScript.

Best practices

Use Vitest for unit, integration, and component tests.

Leverage snapshot testing, mocking, and parallel execution.

Installation: npm install -D vitest Run tests:

npx vitest run

4. Compatibility with Bun

Bun is a new JavaScript/TypeScript runtime focused on performance. While it cannot fully replace Node.js yet, making projects compatible with Bun signals forward‑thinking development.

Why it matters

Ultra‑fast runtime and tooling.

Built‑in TypeScript support.

Integrated bundler, test runner, and package manager.

Best practices

Ensure your project runs on both Node and Bun.

Avoid relying on Node‑specific APIs unless necessary.

Use polyfills or abstraction layers when needed.

bun install
bun run index.ts

Bun is ideal for lightweight servers, build tools, or CLI applications.

5. Even small projects should use TypeScript

TypeScript is now the standard configuration for Node.js development.

Why it matters

TypeScript defines variable, parameter, and return types, allowing the compiler to catch type errors early and easing onboarding for developers from other languages.

Best practices

Configure tsconfig.json with strict mode.

Prefer interfaces and types to define contracts and data models.

Combine with runtime validation tools like zod for safer I/O.

import { z } from 'zod';
const UserSchema = z.object({
  name: z.string(),
  age: z.number().min(18),
});
const input = { name: 'Alice', age: 25 };
const parsed = UserSchema.parse(input);

6. dotenv remains useful—but don’t hard‑code secrets

Using .env files to manage configuration is still valid, but in production you should validate them with tools and avoid committing secrets.

Best practices

Use dotenv only in development or test environments.

Validate configuration with env-var or zod.

Never store secret values in version control.

import { config } from 'dotenv';
config();
import { cleanEnv, str, port } from 'envalid';
const env = cleanEnv(process.env, {
  NODE_ENV: str(),
  PORT: port({ default: 3000 }),
});

7. Zero‑configuration development environment

Tools like tsx, bun, and nodemon simplify development. Prefer zero‑config CLI tools. tsx: Run TS files directly with ESM support. bun: Run .ts and .js files with built‑in TypeScript. nodemon: Auto‑reload the app on code changes.

Run with tsx: npx tsx app.ts Run with nodemon:

nodemon app.js

8. Use PM2 to keep your Node app online

In production, Node.js apps need resilience. PM2 handles restarts, monitoring, clustering, and log management, making it ideal for non‑containerized or self‑hosted servers.

Why it matters

PM2 provides process restarts, monitoring, clustering, and log rotation without downtime.

Best practices

Run and monitor your app with PM2.

Enable cluster mode to fully utilize multi‑core CPUs.

Use log rotation and automatic restarts.

npm install -g pm2
pm2 start app.js --name my-app

Cluster mode example:

pm2 start app.js -i max

-i max

: Launch as many instances as CPU cores using Node’s built‑in cluster module.

View logs with pm2 logs.

PM2 also supports ecosystem configuration files and integrates with Docker and CI/CD pipelines.

Summary

Node.js in 2025 is faster, more modern, and more streamlined than ever, but only if you keep up with current practices. Embrace ES modules, native APIs, and cutting‑edge tools like Vitest and Bun to write cleaner code and become a more efficient developer.

Whether you’re building REST APIs, CLI tools, or full‑stack applications, the future of Node.js is modular, fast, and type‑safe.