If you've built backend APIs in Node.js, there's a good chance you've used Express . For years, Express has been the default choice for building web servers in Node.js . But recently, another framework has been getting a lot of attention: Fastify . Developers often say things like: "Fastify is way faster than Express." But what does that actually mean? And more importantly — should you switch to Fastify? In this article, we'll break it down in simple terms. We'll compare: Performance characteristics Developer experience Architecture and design philosophy Real-world benchmarks When you should choose each framework Let's start with a quick introduction. What is Express? Express.js is a minimal and flexible web application framework for Node.js . Released in 2010, it quickly became the most popular backend framework in the JavaScript ecosystem. It focuses on simplicity and flexibility. A basic Express server looks like this: const express = require ( ' express ' ); const app = express (); app .…