There's another community post with 404 debugging tips that might be helpful. Please give these solutions a try and let us know how it goes.

https://community.vercel.com/t/debugging-404-errors/437

Vercel Community

Debugging 404 Errors

Sometimes things don’t go as expected when deploying a website. If you see a 404 on your site, that means the page or resource couldn’t be found. There are...

A human should be around soon to offer more advice. But you can also get helpful information quickly by asking v0.

Hi Cashiprocom,

The biggest clue is the 39ms build time plus builds: [] and routes: null. That usually means Vercel did not actually build a Next.js app, even though the deployment ended as “Ready”.

I’d check these first:

1
Project Settings → Build and Deployment
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Root Directory: apps/web
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Framework Preset: Next.js
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Build Command: npm run build
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Output Directory: leave empty/default
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Then confirm the connected Git branch really contains a Next app at that path:

1
apps/web/package.json
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apps/web/app/page.tsx or apps/web/pages/index.tsx
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apps/web/next.config.js or next.config.ts, if you use one
4

Inside apps/web/package.json, there should be a build script like:

1
{
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  "scripts": {
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    "build": "next build"
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  }
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}
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After changing that, redeploy with the build cache cleared. In the new build logs, you should see something like:

1
Detected Next.js version ...
2
Running "npm run build"
3

If the build still finishes in a few milliseconds or never says it detected Next.js, Vercel is still looking at the wrong directory or the app files were not pushed to the branch Vercel is deploying.

If apps/web imports shared packages from outside that folder, check the monorepo/workspace setup next, but I’d solve the empty build output first. A real Next.js build should not produce routes: null for an app with pages/routes.