Using import/export in node.js with esm

Using import/export in node.js with esm

When I started using node 6 years ago I took a quick liking to module loading in node. require() is pretty straightforward. You import with require() and export with module.exports.

2 years ago when I started using es6 import / export syntax on the client with webpack, it often became annoying to have to deal with 2 different module loaders in my code. We eventually started using babel on the server so we could use import/export syntax in .es6 files for our app.

I never liked having a build step on the server, and I omit when possible.

Thankfully John-David Dalton (who created Lodash) made the esm module, which allows us to use es6 import/export syntax in node without a build step.

Adding ESM to your project

Esm is a simple npm module.

First we’ll run $ npm install --save esm to install the module.

Then we’ll replace our entry file with this one:

index.js: Our app entry point

In this case we’ve move our app code to main.js which can now contain import/exports! 🎉 ✨

main.js. Where the actual app code lives

The esm loader bridges the ESM of today to the ESM of tomorrow. —

So good. It’s prod ready, fast, and has zero deps.

Published 8 Jul 2018