NestJS vs Express: A Comprehensive Comparison

Posted on 4 April 2025 by techwithnavi.com in Blog

When you start building a server-side app with Node.js, you often need to pick a framework. Two popular choices are NestJS and Express. Both help you create strong APIs and web apps, but they work in different ways. For instance, Express is simple and flexible, while NestJS offers more structure and tools. So, which one should you use? In this article, we’ll explore NestJS and Express step by step. We’ll look at their features, how they work, and when to choose each one. By the end, you’ll know which fits your project best.

What is Express?

Express is a basic web framework for Node.js. It came out in 2010 and quickly became a favorite. Why? Because it’s simple and doesn’t force rules on you. Basically, it adds a light layer to Node.js’s built-in tools, giving you things like routing and middleware. However, it leaves the big decisions—like how to organize your code—up to you.

Key Features of Express

  • Routing: You can easily set up paths like /home or /users and decide what happens there.
  • Middleware: These are small helpers that handle tasks, like checking user logins or logging requests.
  • Lightweight: It doesn’t add much extra weight, so you control everything.
  • Ecosystem: With a huge community, you’ll find tons of add-ons on npm.

For example, Express works great for quick projects. But as your app grows, you might notice it gets messy without careful planning.

What is NestJS?

NestJS is newer—it started in 2017. It’s a modern framework built with TypeScript, which helps catch mistakes early. Unlike Express, NestJS has strong opinions about how things should work. For instance, it uses ideas from Angular, like modules and dependency injection, to keep your code tidy. Plus, it adds extra features right out of the box.

Key Features of NestJS

  • Modules: These group your code into neat sections, making it easier to manage.
  • Dependency Injection: This lets you reuse code without extra hassle.
  • TypeScript: It catches errors as you write, saving time later.
  • Decorators: Simple tags like @Get() make your code clear and short.
  • Extras: Tools for WebSockets or GraphQL are built in, so you don’t need to hunt for them.

In short, NestJS takes Express and adds structure. Actually, it uses Express underneath by default, but you can switch to something faster if you want.

How They’re Built

Express: Simple and Free

Express keeps things minimal. It gives you tools like routing and middleware, but that’s it. For example, there’s no set way to arrange your files. You decide everything. This freedom is great for small apps. However, when projects get big, you’ll need to make your own rules to keep things organized.

Here’s a quick Express example:

const express = require('express');
const app = express();

app.get('/hello', (req, res) => {
  res.send('Hi there!');
});

app.listen(3000, () => {
  console.log('Server is on!');
});

See? It’s super easy. But without extra effort, big apps can turn into a mess.

NestJS: Organized and Clear

NestJS, on the other hand, loves structure. It splits your code into controllers, services, and modules. This keeps everything in its place. For example, controllers handle requests, while services do the heavy lifting. As a result, your app stays clean, even when it grows.

Here’s a NestJS version:

import { Controller, Get, Module, NestFactory } from '@nestjs/common';

@Controller('hello')
export class HelloController {
  @Get()
  sayHi() {
    return 'Hi there!';
  }
}

@Module({
  controllers: [HelloController],
})
export class AppModule {}

async function start() {
  const app = await NestFactory.create(AppModule);
  await app.listen(3000);
}
start();

Notice the difference? NestJS uses tags and modules to keep things tidy.

Learning Them

Express: Quick to Learn

Express is easy to pick up. If you know JavaScript, you can start fast. The docs are simple, and there are tons of guides online. However, using it well in big projects takes practice. You’ll need to figure out how to keep things neat on your own.

NestJS: Takes More Time

NestJS is trickier at first. Why? Because it uses TypeScript and ideas like dependency injection. If you’re new to those, it might feel strange. But once you get it, NestJS makes sense. Plus, its tools and docs help a lot. So, the effort pays off, especially for big projects.

Speed

Express: Fast and Light

Express is quick because it’s so basic. It doesn’t add much extra work for your computer. For example, you can handle lots of requests if you set it up right. But if you add lots of tools—like login systems—it might slow down a bit.

NestJS: A Tiny Bit Slower

NestJS adds some extra steps, like organizing your code. This makes it a little slower than plain Express. However, the difference is tiny. Most of the time, your app’s speed depends more on things like your database. Plus, NestJS can use a faster engine if you need it.

Growing Big

Express: Needs Work

Express can handle big traffic just fine. But growing your code takes effort. For instance, you’ll need to split things up yourself. Without a plan, it’s easy to end up with a jumble. So, it’s great for small teams but harder for big ones.

NestJS: Ready to Grow

NestJS is made for big apps. Its modules and tools help you split work easily. For example, it supports microservices—small apps that talk to each other. As a result, it’s perfect for teams or projects that will get bigger over time.

Community and Tools

Express: Big and Old

Express has been around forever, so its community is huge. You’ll find tools for almost anything on npm. However, some add-ons are old or not kept up. Still, there’s tons of help online if you get stuck.

NestJS: New and Growing

NestJS has a smaller crowd, but it’s getting bigger fast. It comes with tools like database helpers and API docs built in. So, you don’t need as many extras. Plus, it fits with modern coding trends, like TypeScript.

When to Use Each

Use Express If:

  • Quick Projects: Need a fast prototype? Express is your pick.
  • Total Freedom: Want to build your way? It lets you.
  • Simple APIs: For basic apps, it’s plenty.
  • Old Code: Working on something old? Express fits right in.

Use NestJS If:

  • Big Apps: Building something serious? NestJS keeps it solid.
  • Teams: Working with others? It helps everyone stay on track.
  • Fancy Features: Need WebSockets or GraphQL? It’s got them.
  • TypeScript Fans: Love safe code? NestJS is perfect.

Code Side by Side

Express: Simple API

Here’s an Express API:

const express = require('express');
const app = express();

app.use(express.json());

const users = [];

app.get('/users', (req, res) => {
  res.json(users);
});

app.post('/users', (req, res) => {
  const user = req.body;
  users.push(user);
  res.status(201).json(user);
});

app.listen(3000, () => {
  console.log('Server is on!');
});

It’s short and sweet. But it’s all in one place.

NestJS: Same API

Here’s the NestJS version:

import { Controller, Get, Post, Body, Module, NestFactory } from '@nestjs/common';

@Controller('users')
export class UsersController {
  private users = [];

  @Get()
  getUsers() {
    return this.users;
  }

  @Post()
  addUser(@Body() user: any) {
    this.users.push(user);
    return user;
  }
}

@Module({
  controllers: [UsersController],
})
export class AppModule {}

async function start() {
  const app = await NestFactory.create(AppModule);
  await app.listen(3000);
}
start();

See how it splits things up? It’s clearer for bigger apps.

Testing

Express: Do It Yourself

Express doesn’t give you testing tools. You’ll need to add something like Jest and set it up. For example, you’ll write tests for each part yourself. It’s flexible but takes time.

NestJS: Testing Included

NestJS comes with testing ready to go. It works with Jest and makes it easy to test small pieces. So, you save time and effort.

Good and Bad

Express

Good:

  • Super light and fast.
  • Easy for beginners.
  • Tons of help online.
  • You’re in charge.

Bad:

  • Can get messy.
  • Needs extra setup for big stuff.
  • No TypeScript built in.

NestJS

Good:

  • Keeps things neat.
  • Has TypeScript ready.
  • Lots of tools included.
  • Great for teams.

Bad:

  • Harder to learn.
  • A bit heavier.
  • Smaller community.

Wrapping Up

So, which one wins? It depends on you. For example, pick Express if you want something quick and simple. It’s great for small jobs or when you like total control. On the other hand, choose NestJS if you’re building something big or working with a team. Its structure and tools make life easier as things grow. Both are awesome in their own way. Therefore, think about your project, and you’ll find the right fit!

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