Dev build broken with Turbopack and Next.js 15 latest

[fungilation]

What is the problem?

with Next 15.0.3, blitz dev --turbo:

the error log is misleading (maybe) with the imports in node_modules/blitz/dist/chunks/index-browser.mjs, as the culprit is The export default was not found in module [project]/node_modules/.blitz/turbopack-empty.js [client] (ecmascript).

bisecting which Next version broke this, it started with 15.0.0-rc.1. 15.0.0-rc.0 and 14.x worked fine in dev --turbo

Paste all your error logs here:

with Next 15.0.3, dev --turbo:

with Next 15.0.0-rc.0, dev --turbo:

Paste all relevant code snippets here:

N/A

What are detailed steps to reproduce this?

1. blitz dev --turbo with different Next versions
2. also tested different Blitz versions, isn't a factor. Both 2.0.10 and 2.1.3 lead to same error

Run blitz -v and paste the output here:

macOS Unknown | darwin-x64 | Node: v23.3.0

blitz: 0.45.5 (global)
blitz: 2.1.3 (local)

  Package manager: npm
  System:
    OS: macOS 14.7.1
    CPU: (8) x64 Apple M1
    Memory: 83.97 MB / 16.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 23.3.0 - /usr/local/bin/node
    Yarn: 1.22.22 - /usr/local/bin/yarn
    npm: 10.9.0 - /usr/local/bin/npm
    Watchman: Not Found
  npmPackages:
    @prisma/client: Not Found
    blitz: 2.1.3 => 2.1.3
    prisma: Not Found
    react: 19.0.0-rc-66855b96-20241106 => 19.0.0-rc-66855b96-20241106
    react-dom: 19.0.0-rc-66855b96-20241106 => 19.0.0-rc-66855b96-20241106
    typescript: ~5.4.5 => 5.4.5

Please include below any other applicable logs and screenshots that show your problem:

No response

[mischnic]

vercel/next.js#73503 (comment):

This is caused by that [project]/node_modules/.blitz/turbopack-empty.js file. So it's not a Turbopack issue but a blitz one.

Turbopack correctly detects that you are trying to import the default export of a file containing export {}. Which would never work.

They should instead try to do module.exports = {} in that file (or something like that using CommonJS), because that can't be statically analyzed.