What is going on
You asked Codex for one change. It edited several files, and now the app shows an error, a blank page, or won't build at all. You cannot tell which of the changes caused it.
Error messages you might see
Common causes
- The request was broad, so Codex touched files that had nothing to do with it.
- Codex could not run your app or tests in its own environment, so it never saw the error you see.
- To make an error go away, it removed a check or a setting instead of fixing the cause.
- It added or updated a package, which changed the lock file and other packages with it.
- It relied on an environment variable or a service that exists on your computer but not in its workspace.
How to fix it
- See what changed. If the project uses git, run
git statusandgit diff. If Codex made a pull request, open it and read the list of changed files. - Save your current state before undoing anything:
git add -A && git commit -m "Codex changes, broken", on a new branch if you can. - Undo the part that broke it.
git restore path/to/filerestores one file, andgit revertundoes a whole commit. - Read the first error in the log, not the last one. The last ones are often caused by the first.
- Ask for the change again in small pieces, one at a time, and run the app after each piece.
- Ask Codex to explain a change before you accept it. If you cannot follow the explanation, that is the part to show a developer.
- If the project is not in git yet, start now. It is what lets you go back.
Getting help takes about a minute
No hiring, no back and forth. A real person looks at your app.
-
1
Describe it
Tell us what you need in plain words. You don't have to be technical or have an account to start.
-
2
Free 15-minute call
A verified developer calls you. Many tasks are sorted right there, and it costs nothing.
-
3
Pay after you approve
If there is more to do, you get one fixed price up front. You pay only once you are happy.
Real people, reviewed by hand
Developers who do this every day
Every developer is approved by our team before they can take a task. Describe yours and the first one who is free picks it up.
Get help
prajwalfullstack
Most tech stack Im comfortable
Hi Im a full stack developer, a vibe coded MVP to Market ready product, I'm here to help
Mehdi Ben Haddou
react · nextjs · supabase · vercel · ...
- Founder of Chessigma (1M+ users) & many small projects
- ex Founding Engineer @Uplane (YC F25)
- ex Software Engineer @Amazon and @Booking.com
Vlad Temian
react · supabase · postgresql · typescript · tailwind · python · django · stripe · docker · kubernetes · security · authentication · deployment · nextjs
15+ years shipping production infrastructure for startups. Former CTO at qed.builders (acquired by The Sandbox).
Cursor ambassador and agentic tooling builder.
I've scaled systems, automated deployments, and built observability tools for AI coding workflows. I specialize in taking vibe-coded apps from broken prototype to production-ready: fixing Supabase auth/RLS, Stripe integrations, deployment pipelines, and cleaning up AI-generated spaghetti.
I build tools in this space (agentprobe, claudebin, micode) and understand both sides: how AI generates code and why it breaks.
https://blog.vtemian.com/
Questions
Can I undo what Codex did?
Yes, if the project is in git. git restore brings back a single file and git revert undoes a commit. Commit your current state first so nothing is lost.
Why did Codex change files I never mentioned?
A broad request gives it room to edit related files. Asking for one small change at a time keeps the edits easy to check.
