Fix guides
When an app built with an AI builder breaks: the likely cause, how to confirm it, and how to fix it yourself.
- Why your first customer leaves: what we found testing 37 newly launched AI-built appsWe tested 37 newly launched AI-built apps the way a first customer would. 28 had a problem that would stop one. The most common dead ends, and how to check your app for each.
- App shows a blank page after publishing (but works in the preview)Your Lovable, Bolt or Base44 app works in the preview but the published site is a white screen. The usual causes, how to confirm yours in 2 minutes, and the fix.
- Works in the preview, breaks after deploy: the 4 differences that cause itYour Bolt, Lovable or v0 app works in the preview but breaks on Netlify, Vercel or your custom domain. The four differences between preview and production, and how to fix each.
- Sign-up or login broken after publishing (Supabase redirect URLs)Users can't log in on your published Lovable or Bolt app: they bounce back to the login page, land on localhost, or see an error. Why it happens and the exact settings to fix.
- Data won't save: 'new row violates row-level security policy'Your Lovable or Bolt app can't save data, or users see each other's data. What Supabase row-level security is, how to read the error, and how to fix it without switching security off.
- 'Page not found' when you refresh or open a link directlyYour AI-built app's home page works, but refreshing any other page or opening a shared link shows 404 Page Not Found. Why hosts do this and the one-line fix for Netlify and Vercel.
- Sign-up confirmation emails never arriveNew users of your Lovable or Bolt app never get the confirmation or password-reset email, so they can't finish signing up. Why Supabase's built-in email stops, and how to fix it.
- Stripe payments work in test mode but fail on the live siteCheckout works with Stripe's test card, then fails or doesn't unlock anything once real customers pay. The live-mode settings AI-built apps usually miss, and how to check each.
- My AI-built app doesn't show up on GoogleYour Lovable, Bolt or Base44 app is live but Google doesn't find it. The settings that hide AI-built apps from search engines, and the steps to get indexed.
- The AI says it fixed it, but it's still broken (and now something else is too)You asked Lovable, Bolt or Cursor to fix a bug, it said 'Fixed!', and it's still broken, or it broke something that worked. Why AI builders loop, and how to break the loop.