Error Index

Errors people actually search for when building on AI app builders — what causes them, and how to fix them.

All platforms Base44 Bolt Lovable Netlify Railway Supabase Vercel v0

Vercel

API key visible in the client bundle

API key exposed in client bundle

Build succeeds but the deployed site returns 404

404 This page could not be found

Environment variables work locally but are undefined in production

undefined is not an object (evaluating 'process.env')

Lovable app deploys to Vercel successfully but every route returns 404

404: NOT_FOUND

Error Index | Opsily