Fundamentals7 min read271 words
Why vibe-coded apps survive the demo and break in production
The walkthrough was flawless. Then real users, real data, and real concurrency arrived. Here is what fails — and how we stabilise it.
Rehan Goraya
Founder & Head of Product Development · Published 15 Sept 2026
Demos are curated: one user, clean data, a warmed cache, and a narrator who knows which buttons to avoid. Production is the opposite — and AI-built apps often encode demo assumptions into the architecture.
When we are called after launch week, the failures cluster. Fixing them means making those assumptions explicit and replacing them with boring, durable patterns.
1. Happy-path state only
Nulls, partial records, retries, and double-submits were never modelled. Add validation at the edges, idempotent writes for payments and forms, and UI states for empty/error/loading that match reality.
2. One-user concurrency assumptions
Race conditions appear when two tabs or two users touch the same row. Use transactions, unique constraints, and locks where the business rules demand a single winner.
3. Environment drift
Local SQLite, production Postgres, missing env vars, and different Node versions create “works on my machine” outages. Unify runtimes and fail fast when config is incomplete.
4. Background work that only ran in the demo
Email, webhooks, and cron tasks often depended on a laptop process staying awake. Move them to real queues or scheduled functions with retries and dead-letter handling.
5. No signals when things die
Without structured logs and error tracking, you learn about outages from customers. Instrument the critical path before you scale ads.
6. Schema changes without a plan
AI migrations sometimes drop columns or lock tables casually. Expand/contract migrations, backfill carefully, and never run destructive SQL first on production.
7. No regression net
A short checklist for signup, login, checkout, and the core create/read flows — automated where possible — catches the “fix one thing, break another” pattern that vibe coding amplifies.
Questions people ask
- Production
- Reliability
- Architecture
- QA
Written by
Rehan Goraya
Founder & Head of Product Development, Fixthevibecode
Building software products since 2019. Every enquiry is read and answered by me personally, not by a sales team.
