TechFixError fixes
Error fixes for AI-built apps
One page per error people search at the moment something goes wrong. Each one gives the exact error, the cause in plain words, the fix by hand, how to stop it coming back, and the official docs we checked on 2026-10-13.
It worked on your laptop. Production disagrees.
The skill for these: Broke After Deploy ($9).
- Module not found on Vercel, but it works locally
Module not found: Can't resolve './components/Header' - EROFS: read-only file system on Vercel or AWS Lambda
Error: EROFS: read-only file system, open '/var/task/data/posts.json' - ECONNREFUSED 127.0.0.1:5432 in production
Error: connect ECONNREFUSED 127.0.0.1:5432 - CORS error only in production, but it works on localhost
Access to fetch at 'https://api.example.com/items' from origin 'https://www.example.com' - redirect_uri_mismatch after deploy (Google sign-in)
Error 400: redirect_uri_mismatch - Prisma P1001: Can't reach database server in production
Error: P1001: Can't reach database server at `db.example.com:5432` - SQLITE_CANTOPEN on Vercel or serverless hosting
SQLITE_CANTOPEN: unable to open database file - The edge runtime does not support Node.js 'crypto' module
Error: The edge runtime does not support Node.js 'crypto' module. - useSearchParams() should be wrapped in a suspense boundary
useSearchParams() should be wrapped in a suspense boundary at page "/search". - NEXT_PUBLIC_ variable is undefined in production
console.log(process.env.NEXT_PUBLIC_API_URL) // undefined
A secret got out. Rotate first, then clean up.
The skill for these: Key Leaked ($7).
- OpenAI API key leaked: what to do right now
401 Incorrect API key provided - GitHub secret scanning alert: what to do next
Secret scanning alert in your repository's Security tab - Remove .env from git history (rotate first)
$ git log --all --oneline -- .env - AWS exposed credentials and AWSCompromisedKeyQuarantineV3
Policy attached: AWSCompromisedKeyQuarantineV3 - Stripe secret key exposed: rotate it safely
sk_live_... or rk_live_... exposed
Something ran up a bill. Stop it, then cap it.
The skill for these: Bill Spiked ($7).
- Unexpected OpenAI API charges
429 project_spend_limit_exceeded - Firebase bill spike
Budget alert email, one product far above normal - Twilio SMS pumping: unexpected SMS charges
SMS to blocks of adjacent numbers, error 30450 or 60410 - Vercel bill spike from image optimization or functions
503: DEPLOYMENT_PAUSED
The agent said it works. It doesn't.
The skill for these: Prove It Works (Free).