Link to the code that reproduces this issue

https://github.com/mikan3rd/nextjs-workspace-bug-reproduction

To Reproduce

1. Create a pnpm workspace with a Next.js application (e.g., "main_app")
2. Configure the Next.js app with output: 'standalone' in next.config.ts
3. Run next build in "main_app" directory
4. Check the generated standalone output directory

Current vs. Expected behavior

Current behavior:
The standalone build creates the server.js file at .next/standalone/main_app/server.js
This breaks existing deployment scripts and Docker configurations that expect the server.js file to be at the standard location.

Expected behavior:
The standalone build should create the server.js file at .next/standalone/server.js as it did in previous versions

Provide environment information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 24.6.0
Binaries:
  Node: 22.13.0
  pnpm: 10.15.1
Relevant Packages:
  next: 15.5.3
  typescript: 5.9.2
Next.js Config:
  output: standalone

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

Output

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

next build (local)

Additional context

This issue appears to be introduced in Next.js 15.5.0 and affects projects using:

• output: "standalone" configuration
• pnpm workspace environment

The issue causes the standalone build to include the package name in the output path structure, which breaks existing deployment configurations and scripts that expect the standard .next/standalone/server.js path.
This is particularly problematic for Docker deployments and CI/CD pipelines that rely on the predictable standalone output structure.
Workaround: Currently, users need to update their deployment scripts to account for the package name being included in the path, or modify their package.json name to avoid this issue.
Impact: This affects any project using standalone mode with pnpm workspaces, requiring changes to deployment configurations and potentially breaking existing Docker images and deployment scripts.