# Built an MVP in 3 days with Claude Code — here's the stack

> Source: <https://promptcube3.com/en/threads/7062/>
> Published: 2026-08-20 16:03:10+00:00

# Built an MVP in 3 days with Claude Code — here's the stack

[Claude Code](/en/tags/claude%20code/)"build the smallest thing that proves people will pay for this." The result? A working SaaS prototype with Stripe billing, user auth, and a dashboard — deployed to Vercel before the weekend ended.

The old MVP playbook hasn't changed: identify a real problem, define one core value prop, strip everything else. What *has* changed is how fast you can validate. AI coding tools compress the build-measure-learn loop from weeks to days.

**My current validation stack**

— primary IDE, Cmd+K for inline edits, Composer for multi-file features[Cursor](/en/tags/cursor/)— terminal agent for scaffolding, migrations, test generation[Claude](/en/tags/claude/)Code**v0.dev**— instant UI components when I don't want to write Tailwind** Supabase**— auth + database + edge functions in one PostgreSQL backend** Vercel**— zero-config deploy, preview URLs for every push

**The 3-day sprint breakdown**

Day 1: Problem validation before code. I wrote a one-pager, posted in two relevant Discords, got 12 people saying "shut up and take my money." Only then did I open Cursor.

Day 2: Scaffold → authenticate → charge. Single prompt to Claude Code:

```
Create a Next.js 14 app with Supabase auth (email/password + OAuth),
a /dashboard route protected by middleware, and a Stripe Checkout
integration that creates a subscription on success. Use TypeScript,
Tailwind, and App Router. Output the full file tree.
```

Got a working repo in 45 minutes. Spent the rest of the day styling the pricing page and writing the webhook handler.

Day 3: Polish the happy path. Added loading states, error toasts, email confirmation flow. Deployed. Sent the preview link to the 12 people from Day 1. Three converted to paid before Monday.

**What I skip now (and you should too)**

- Custom UI component libraries — v0 + shadcn/ui covers 90%
- Manual API route boilerplate — Supabase edge functions + generated types
- Test suites for throwaway code — E2E tests only for the payment flow
- Admin panels — SQL queries in Supabase dashboard until revenue justifies it

**The trap to avoid**

AI makes overbuilding *easier*, not harder. You can generate a full admin dashboard, analytics pipeline, and notification system in an afternoon. Don't. Every feature you add before charging a single user is a hypothesis you haven't tested.

**My rule now**: one paid user > 100 GitHub stars. The code quality of my Day 2 scaffold was embarrassing — hardcoded secrets, no tests, console.logs everywhere. But it *worked*, and that's the only metric that mattered.

Next sprint: replace the Stripe webhook with a proper event-driven architecture using Upstash QStash. But only because MRR demands it.

What's the longest you've spent on an MVP before getting a single dollar?

[Next The dead giveaways that a site was vibe coded →](/en/threads/6943/)