Cannot use Next.js as a transitive dep to build an application

[Ethan-Arrowood]

Link to the code that reproduces this issue

https://github.com/Ethan-Arrowood/next-issue-repro

To Reproduce

Follow readme in https://github.com/Ethan-Arrowood/next-issue-repro

Or:

1. Generate a new nextjs app, npx create-next-app. Called it my-app
2. As a sibling to the next app created in step 1, create a new directory next-transitive
3. Add a package.json with the content: { "dependencies": { "next-app": "file:../my-app" } }
4. cd into next-transitive and run npm install --install-links (the option is so that the file: is actually installed instead of symlinked)
5. cd into node_modules/next-app and try to run npx next build or npm run build. They will both fail with the following:

> my-app@0.1.0 build
> next build

   ▲ Next.js 15.0.3

   Creating an optimized production build ...
Failed to compile.

./app/page.js
Module parse failed: Unexpected token (6:4)
File was processed with these loaders:
 * ../next/dist/build/webpack/loaders/next-flight-loader/index.js
 * ../next/dist/build/webpack/loaders/next-swc-loader.js
You may need an additional loader to handle the result of these loaders.
| export default function Home() {
|   return (
>     <div className={styles.page}>
|       <main className={styles.main}>
|         <Image

Import trace for requested module:
./app/page.js


> Build failed because of webpack errors

Current vs. Expected behavior

This behavior seems to exist for a few major versions. My assumption is that the build process is not resolving its own dependencies correctly.

Provide environment information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 23.6.0: Mon Jul 29 21:14:30 PDT 2024; root:xnu-10063.141.2~1/RELEASE_ARM64_T6030
  Available memory (MB): 18432
  Available CPU cores: 12
Binaries:
  Node: 20.16.0
  npm: 10.8.1
  Yarn: N/A
  pnpm: N/A
Relevant Packages:
  next: 15.0.3 // Latest available version is detected (15.0.3).
  eslint-config-next: N/A
  react: 19.0.0-rc-66855b96-20241106
  react-dom: 19.0.0-rc-66855b96-20241106
  typescript: N/A
Next.js Config:
  output: N/A

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

Developer Experience, Script (next/script), SWC, Webpack

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

next build (local)

Additional context

No response

[Ethan-Arrowood]

A quick solution is to use npm install --install-strategy=nested. This is okay I guess, but could impact other things so I wouldn't call it a true solution.