Guides
Guides for AI-built apps
Step-by-step fixes for Lovable, Bolt, Replit, Cursor, and Supabase: permission errors, blank production pages, login that works locally but not live, and what to retest after an AI edit.
Cursor broke my app: how to revert the changes
Cursor's agent broke working code? Roll back with Restore Checkpoint, Local History or git, and set up git so the next bad edit takes one command to undo.
Bolt.new works in preview but not on Netlify
Bolt app fine in preview but blank or broken on Netlify? It's usually missing VITE_ env vars, the wrong publish folder, Node version or auth URLs.
Supabase service role key exposed in your frontend JavaScript
Found a Supabase key in your app's JS? The anon/publishable key is meant to be public; a service_role or secret key isn't. Check which, then rotate.
"new row violates row-level security policy": the real fix
Supabase returns 'new row violates row-level security policy' or empty arrays in your Lovable, Bolt or Cursor app. Here's the actual fix: add the right RLS policy, and don't turn RLS off.
Did the AI break something? A checklist to run after every edit
A practical checklist for non-developers to confirm a Lovable, Bolt, Cursor or Replit edit didn't break signup, login, data access or the live site, plus how to roll back safely.
Lovable app shows "Failed to fetch" or a CORS error after deploy
Lovable app shows 'Failed to fetch' or a CORS error once live? Check Supabase env vars, edge function CORS headers, OPTIONS handling and redirect URLs.
Your app works in preview but shows a blank page in production
Your AI-built app works in preview but shows a blank page once deployed. Here's how to find the error and fix missing VITE_ environment variables on Vercel, Netlify or Lovable.
Replit publish failed: how to find the real error
Replit app builds fine but publishing fails or the live app breaks. Step-by-step fixes for 'port was never opened', paused databases, missing production secrets and the wrong deployment type.
Supabase 42501 "permission denied for table": Causes and Fixes
Getting Supabase error 42501 permission denied for table? Here's why it happens, including the Oct 30, 2026 explicit-GRANT change, plus SQL fixes for GRANTs and RLS policies.
Supabase login works locally but not on the live site
Login or signup works on localhost or in the Lovable preview but fails on Vercel or your custom domain. Step-by-step fixes for Site URL, redirect URLs, env vars, email and OAuth.