Worker Threads with TypeScript

[idleberg]

I'm making my first experiences with NodeJS worker threads and ran into something that makes me wonder if tsdown (or Rolldown) needs to address this. It should be noted that I did not find anything for other bundlers. But let me describe my problem first:

import { Worker } from 'worker_threads';

const worker = new Worker('./worker.ts', { // ← it's about the first argument
  workerData: {},
});

This works fine before bundling, since worker.ts is a file in my source folder. However, once bundled, this file will be named worker.mjs – I will run into a "file not found" error at runtime.

I can imagine employing a couple of workarounds for this:

• use .mjs in the source
• use a plugin such as @rollup/plugin-replace
• create a barrel .mjs file that imports .ts

What's your opinion on this? Do you feel this is something that should be handled by a bundler? If so, is this the right repository to bring this up or should it be escalated to Rolldown?