Express is getting old and out of date. Learn what makes Fastify a great alternative, and how to migrate an existing Node.js app from Express to Fastify.

Express has long been the most popular framework for developing web applications with Node.js. Unfortunately, this framework hasn’t seen much active development in recent years. This means that it doesn’t have support for modern JavaScript features. In the meantime, a number of new frameworks have emerged which take a different approach to Node.js application development. One of these frameworks is Fastify.

In this article, we’ll look at what makes Fastify an appealing alternative for developing web applications with Node.js. We’ll learn how we can avoid the need to rewrite our existing Express applications from scratch, and instead migrate them to using Fastify in phases. By the time we’re done, you’ll be able to confidently migrate your existing Express applications and start leveraging the benefits of the Fastify framework.

There are a few requirements for following along with this article:

• You’ll need to be comfortable with creating a basic Express application, defining routes and configuring middleware.
• You’ll need to be comfortable running commands in a terminal.
• You’ll need to have Node.js >= v14.13.0 installed. This provides us with good support for ECMAScript (ES) modules and allows us to use top-level await. The code examples in this article use ES module syntax (import / export).

All of the example code in this article is available on GitHub for you to browse, download and experiment with.

#express #fastify #node #javascript