DEV Community

Node.js, TypeScript and ESM: it doesn't have to be painful

Alejandro Oviedo on December 11, 2023

I was thinking into starting a Node.js project from scratch and had an unsettling choice to make: to use ESM or CommonJS. The decision of a few po...

Read full post

BinaryBitBytes • Dec 13 '23 • Edited

Thank you so much for this. I seriously had this problem today when dealing with imports from typescript to js and mjs.

Pablo Chiappetti • Mar 16

Thanks Ale :) Was struggling to understand current state of Node + TS + ESM support and you nailed it here.

Alejandro Oviedo • Mar 19

Glad it was helpful to you Pablito!

Liran Tal • Jan 24

Nice write-up Alejandro!

Do you find it a better alternative to avoid the "type":"module" and instead just use "main" and "module" as keys (potentially with "exports" too) to avoid the "type" declaration which hardly requires the project to run as a module too?

Alejandro Oviedo • Mar 19

Thanks @lirantal! I have tried alternatives but in the end type was simpler and easier for people to understand. I feel like "exports" is a rabbit hole where you need to know exactly what you're doing or you are lost.

Liran Tal • Mar 19

Yes agree that exports makes it a bit more harder on discovery :-)
Thanks!

Jeff Tillwick • Oct 21

Can someone, for the love of all that is good, please explain to me in a way that actually makes sense WHY anyone would want to import something with an extension? PLEASE! Help me understand why ANYONE would want to do this?

fury-r • Mar 2

I tried the above .swcrc file. It didn't seem to work. I checked on playground got alot of errors.Finally i tried the below config it worked.Thanks for explaining how to do it.
{
"jsc": {
"parser": {
"syntax": "typescript",
},
"target": "es2022",
"loose": false,
"minify": {
"compress": false,
"mangle": false
}
},
"module": {
"type": "es6"
},
"minify": false,
"isModule": true
}
.swcrc