[Turbopack] SharedWorker TypeScript scripts not compiled

[christoph-pflueger]

Link to the code that reproduces this issue

https://github.com/christoph-pflueger/turbopack-shared-worker-reproduction

To Reproduce

1. npm run dev
2. Visit http://localhost:3000/
3. Open the console. In Chrome you will notice the error Failed to fetch a worker script..
4. Open chrome://inspect/#workers in Chrome. You will notice that only the SharedWorker with the .js script is running and has logged Hello world!.

Current vs. Expected behavior

I expect to be able to run a SharedWorker with a TypeScript script.

Currently, the SharedWorker fails to run.

It appears that the script is not even being compiled: .next/static/media/script.93184b23.ts

Provide environment information

Operating System:
  Platform: linux
  Arch: x64
  Version: #1 SMP Tue Nov 5 00:21:55 UTC 2024
  Available memory (MB): 15948
  Available CPU cores: 12
Binaries:
  Node: 22.13.0
  npm: 10.9.2
  Yarn: N/A
  pnpm: 9.15.3
Relevant Packages:
  next: 15.2.0-canary.7 // Latest available version is detected (15.2.0-canary.7).
  eslint-config-next: N/A
  react: 19.0.0
  react-dom: 19.0.0
  typescript: 5.7.3
Next.js Config:
  output: N/A

Which area(s) are affected? (Select all that apply)

Turbopack, TypeScript

Which stage(s) are affected? (Select all that apply)

next dev (local)

Additional context

No response