Guide · v0
Fix a broken v0 app
Updated
Short answer
A v0 app is deployed to Vercel, and the same app answers at a preview address and a production address. Many launch problems can come from settings that exist in one of those places and not the other: environment variables, sign-in redirect addresses and database permissions. Check those, then test the live address in a private window. If it is still broken, a free VibeFix check tries the problem on your live app, and the fix in the code is $79, paid up front.
This page is about apps built with v0. The name is used only to say which tool this is about.
How a v0 app breaks once real users arrive
v0's docs say: "v0 deploys projects to Vercel. Working branches get preview deployments for review, while publishing updates the Vercel project's production deployment and stable production URL." v0 also lists Supabase, Neon, Upstash and Vercel Blob among its database integrations.
- Works in preview, not live. Preview deployments have "unique URLs and do not change the project's production URL." See Works in the preview but not after publishing and v0: environment variables missing on the published app.
- Sign-in sends people to the wrong address. If you use Supabase, the Site URL and redirect list must include your production address. See v0 with Supabase: sign-in sends people to the wrong URL, Supabase redirect URL goes to localhost and Login broken after publishing.
- Emails not arriving. See Confirmation emails not arriving for a Supabase-based app.
- Data not saving. With a Supabase database, access rules apply. See Data won't save (row-level security).
- 404 or a broken page after deployment. A Next.js app on Vercel can return 404 or fail on images. See 404 on Vercel right after deployment, Images return 400 and Blank page after publish.
- Payments. v0's first-publish flow includes a step to "Review unclaimed Stripe test sandboxes or Shopify development stores", a reminder that test and live setups differ. If customers cannot pay, see Customers can't pay and Stripe checkout not working on the live site.
What you can try yourself first
- Open the deployment card. v0's deployments docs say it reports build progress and links to "Build logs and errors." For a GitHub-backed project, the branch menu offers actions such as Fix Build and Fix CI.
- Check environment variables. v0 says you can add your own anytime from Project menu, Settings, Environment Variables (databases docs). Then publish again and test the production address.
- Publish the latest changes. Use Publish Changes after each code change.
- Check the Supabase address list if you use it for sign-in.
- Test as a stranger: a private window, a new email address, the production address.
How VibeFix helps
VibeFix is independent of any app builder. Our AI agent can fix a v0 app in its code when the code is on GitHub. v0 says you can "Connect a v0 project to GitHub to keep its code in a repository" (GitHub docs).
- Free check. "You tell us what broke. Our AI agent tries it on your live app, says whether it hit the same problem, and sends a screenshot."
- Fix. "Our AI agent finds the cause and fixes it in your code." The price is "$79, paid up front."
- Delivery and re-check. "A GitHub pull request in your own repository." After the fix is live, the AI agent goes back to your live app and repeats the check that failed, the way a customer would.
- Refund. "If we can't complete your re-check, you get your money back."
- Which apps. "Today the fix is for apps built with Lovable, or any app whose code is on GitHub."
- Never asked. "We never ask for passwords."
A check reports what the AI agent saw. It does not promise that every problem is found.
Want it fixed?
Our AI agent fixes it in your code and tests your live app again. See pricing.
It starts with a free check that confirms the problem on your live app, no account needed.
VibeFix is independent. Lovable, Bolt, Replit, Base44, v0, Supabase, Firebase, Stripe, Vercel and Google are trademarks of their owners.
Want it fixed?
Our AI agent fixes it in your code and tests your live app again. See pricing.
It starts with a free check that confirms the problem on your live app, no account needed.