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Vercel rescue guide
Vercel deployment fails for your AI-built app
VercelNext.js
Short answer
A clean Vercel deploy with correct build config, environment variables, and framework settings.
Why this matters
The build passes locally or in the AI builder, but Vercel fails with cryptic errors about missing outputs, wrong runtime, or build timeouts.
Walkthrough
- 01
Read the Vercel build log
Vercel tells you exactly what failed. The trick is knowing what to look for.
- Find the first error in the build log, not the last.
- Check whether the build command, output directory, and framework preset are correct.
- Look for missing environment variable warnings that caused the build to fail.
- 02
Fix the build configuration
Align Vercel settings with what the AI builder actually produces.
- Set the correct framework preset (Next.js, Vite, Remix, or Other).
- Confirm the build output directory matches the framework default.
- Add any missing environment variables to the Vercel project settings.
- 03
Test and deploy
Trigger a new deploy and verify the app loads on the Vercel URL.
- Push a commit to trigger a fresh Vercel build.
- Confirm the app loads, auth works, and database calls succeed.
- Set up the custom domain and HTTPS after the build passes.
Where RepoAssistant fits
RepoAssistant diagnoses and fixes Vercel deploy failures for AI-built apps, or moves them to a VPS when Vercel is the wrong fit.