nextjs - 💡(How to fix) Fix Turbopack: Path doubling with outputFileTracingRoot in monorepo causes vercel build failure [1 comments, 2 participants]

Error: ENOENT: no such file or directory, lstat '/path/to/apps/frontend/apps/frontend/.next/routes-manifest.json'

TL;DR

• Adjust the outputFileTracingRoot configuration to prevent path doubling during the Vercel build process.

Guidance

• Review the next.config.js file to ensure that the outputFileTracingRoot path is correctly set, considering the current working directory.
• Verify that removing or adjusting the outputFileTracingRoot setting resolves the path doubling issue, while also ensuring that turbopack.root is correctly configured for module resolution.
• Consider alternative configurations for turbopack.root and outputFileTracingRoot that balance the need for correct module resolution and avoidance of path doubling.
• Test the build process with the adjusted configuration to confirm that the issue is resolved.

Example

// Potential adjustment to next.config.js
module.exports = {
  turbopack: {
    root: path.resolve(__dirname, "../.."),
  },
  // Adjust or remove outputFileTracingRoot to prevent path doubling
  outputFileTracingRoot: path.resolve(__dirname),
  output: "standalone",
};

Notes

• The provided solution may require further refinement based on the specific monorepo structure and package dependencies.
• The issue appears to be specific to the combination of Turbopack, Vercel build, and monorepo configuration, so the solution may not apply to other build environments or configurations.

Recommendation

• Apply workaround: Adjust the outputFileTracingRoot configuration to prevent path doubling, as this appears to be the most direct solution to the issue, given the current limitations of Turbopack in monorepo environments.