Difference Between Express and Fastify Web App Frameworks (original) (raw)

Last Updated : 28 Apr, 2025

While building backend applications with Node JS there is a list of frameworks that can be used with Node JS. Two of the most popular choices are Express.js and Fastify. In this article, we will learn about these frameworks and their difference.

Table of Content

• What is Express JS?
• Features of Express JS framework
• What is Fastify?
• Features of Fastify Framework
• Difference between Express and Fastify Web application framework

**What is Express JS?

Express Js is a web application framework for Node JS. It is used to design, scalable, web application APIs. It provides all set of features for developing mobile and web application programs. It is one of the most popular web application frameworks.

**Features of Express JS framework

• **Middleware****:** This is the global function in the express js that can access the request and response. It provides a way for the developer to perform various functions in request and response. for example: Logging and Authentication etc.
• **Routing****:** Express provides a simple and flexible routing system. Routes define how an application responds to client requests for specific endpoints (URLs). It can support various HTTP verbs Get, Post, Put, etc.
• **Error Handling****:** Express Js supports its error handling method. we can catch the error using the middleware function in Express Js for handling the errors.
• **REST APIs Development****:** Express is used mostly for developing the APIs. It simplifies defining API endpoints and handling HTTP requests and responses.

**Example: The following program demonstrates how we can use Express Js.

JavaScript ``

//app.js

const express = require('express');

// Creating an Express application const app = express(); const port = 3000; // Port number on which the server will run

// Define a route for the root URL app.get('/', (req, res) => { res.send('Geeks for Geeks'); });

// Start the server and listen on the specified port app.listen(port, () => { console.log(Server listening on port ${port}); });

``

**Output:

**What is Fastify?

Fastify Web App is also a Node Js framework. Fastify is specifically designed to be a fast web framework. It achieves this by focusing on low overhead and high throughput. Fastify claims to be one of the fastest web frameworks for Node.js.

**Features of Fastify Framework :

• **Performance: It is desgined to be fastest framework in NodeJs. It achieves high performance by minimizing overhead and focusing on the essentials needed for request handling.
• **Schema Based Validation: This allows developers to define the expected shape of request payloads and responses, making it easier to validate and document APIs.
• **Middleware: The fastify web application framework supports middleware also that is used to enaching the functionality of developers their programs.

**Example: The following program demonstrates the Fastify framework example.

JavaScript `

// app.js

const fastify = require('fastify')({ logger: true })

// Declare a route fastify.get('/', function handler(request, reply) { reply.send({ hello: 'Geeks for Geeks' }) })

// Run the server! fastify.listen({ port: 3000 }, (err) => { if (err) { fastify.log.error(err) process.exit(1) } })

`

**Output:

Difference between Express and Fastify Web application framework.