Turbopack panic loop on Windows with pnpm: Next.js package not found + ChunkLoadError on /dashboard

[mirraman]

Link to the code that reproduces this issue

https://github.com/mirraman/turbopack-panic-repro

To Reproduce

1. Create a Next.js App Router project with pnpm on Windows.
2. Use versions:
   • next: 16.2.0
   • react: 19.2.4
   • react-dom: 19.2.4
   • node: v22.14.0
   • pnpm: 10.20.0
3. Run pnpm dev (Turbopack).
4. Open /dashboard and refresh multiple times.
5. Observe terminal + browser console.

Current vs. Expected behavior

Expected behavior

• next dev with Turbopack should not panic.
• /dashboard should render without repeated crashes.
• HMR chunk should load normally.

Actual behavior

• Terminal repeats:
  • FATAL: An unexpected Turbopack error occurred
• Panic log contains:
  • Failed to write app endpoint /dashboard/page
  • Caused by: Next.js package not found
• Browser console shows:
  • unhandledRejection: ChunkLoadError: Failed to load chunk /_next/static/chunks/[turbopack]_browser_dev_hmr-client_hmr-client_ts_....js

Provide environment information

- OS: Windows
- Node.js: v22.14.0
- pnpm: 10.20.0
- next: 16.2.0
- react: 19.2.4
- react-dom: 19.2.4
- Router: App Router

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

Turbopack

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

next dev (local)

Additional context

• Reproducible locally on Windows (not deployment-related).
• Not tied to browser-specific behavior; issue is visible from terminal panic + HMR chunk failure.
• Panic log path:
  • C:\Users\alexb\AppData\Local\Temp\next-panic-9af8463e3b894e5eb6901e1b800b28fa.log
• next is installed and resolvable:
  • node -e "console.log(require.resolve('next/package.json'))"
  • resolves to node_modules/.pnpm/.../next/package.json
• Workaround:
  • next dev --webpack works
  • clearing .next cache helps only temporarily for Turbopack