Consumer marketplace · Canvas (stealth-mode marketplace)
Vibe-Coded Marketplace to Production at 40k MAU
Took a v0-generated MVP that had reached product-market fit and refactored it into a production system supporting 40,000 monthly active users on the original scrappy timeline.
Problem
The founders had built a beautiful marketplace prototype in v0 and Cursor in three weeks. Users loved it. But: RLS was disabled on three tables, the checkout was calling Stripe from the browser with the secret key, p95 was 3.1s under load, and there were no tests. The company had two weeks of runway before their next raise.
Solution
We embedded a two-engineer pod for six weeks. Week 1: full security audit and lock down the three critical vulns without breaking the app. Weeks 2-4: query and schema refactor, move Stripe to server functions, add Playwright coverage on every checkout path. Weeks 5-6: observability, on-call runbook, and hand-off training.
Result
Company raised their Series A on the back of a working, boring, safe platform. p95 dropped from 3.1s to 180ms. Zero prod incidents in the 90 days post-handoff. The founders kept their velocity — they shipped 11 new features in that same quarter without touching the refactor.