Turbopack Error: Failed to write app endpoint /page

[hardik2047]

Turbopack version: 2fb79035
Next.js version: 0.0.0

Error message:

Turbopack Error: Failed to write app endpoint /page

[victormoni]

Hi @hardik2047

That message means Turbopack tried to generate the compiled file for the / page (it writes to .next/**/app/page.*) and couldn’t. In practice this usually comes from one of four causes:

Common causes → fixes

1. Route conflict for “/”

• You have more than one endpoint mapped to / (e.g., both app/page.tsx and pages/index.tsx, or app/page.tsx plus an API route.ts at app/page/route.ts).

• Fix:

  • Keep only one UI entry for /: app/page.tsx (or group variant).

  • Move API handlers under app/api/.../route.ts (not under app/page), and remove any pages/index.* if you’re using the app/ router.

2. Duplicate/invalid files in app/page

• Files like app/page.js and app/page.tsx, or a folder named app/page with its own page.tsx, can collide.

• Fix: Ensure there is exactly one of:

app/page.tsx // or .js/.jsx

and it has a default export.

3. Write-permission or lock on the build output

• The .next (or .turbo) directory is read-only, locked by another process, or synced by tools (OneDrive/Dropbox/antivirus).

• Fix:

rm -rf .next .turbo
# On Unix/WSL, also:
chmod -R u+rw . && find . -type d -name ".next" -prune -o -type f -print >/dev/null

Close any watchers, disable AV sync for the project, and re-run next dev --turbo.

4. Missing/incorrect Next.js install (shows as Next.js 0.0.0)

• Turbopack can’t resolve next, so it can’t write the endpoint.

• Fix (choose your manager):

# npm
rm -rf node_modules package-lock.json && npm i next react react-dom
npm run dev -- --turbo
# yarn
rm -rf node_modules yarn.lock && yarn add next react react-dom && yarn dev --turbo
# pnpm
rm -rf node_modules pnpm-lock.yaml && pnpm add next react react-dom && pnpm dev --turbo

• Make sure you run from the project root and that package.json has:

"dependencies": { "next": "14.x", "react": "18.x", "react-dom": "18.x" }

Extra checks (if it still fails)

• Monorepo: ensure the app package itself depends on next and you run the dev script from that package.

• Node version: use Node ≥ 18.17 (or 20.x).

• Disk/paths: verify free disk space and avoid very long paths or read-only locations (e.g., OneDrive).