Build your own YNAB with Claude Code
A zero-based budgeting app: give every pound or dollar a job, category budgets that roll over, transaction entry and import and more.
The Claude Code prompt
Build my own take on YNAB: a zero-based budgeting app. Give it an original name, logo, colours and copy, and do not use YNAB's name, branding or assets. Version one should have: - Give every pound or dollar a job - Category budgets that roll over - Transaction entry and import - Goals per category - Spending reports The hard part: Bank sync. Start with CSV import and add Plaid later. How to build it: 1. Read this folder first. If it is empty, set up Next.js (App Router, TypeScript, Tailwind) with Postgres through Prisma or Supabase, and Supabase Auth or Auth.js for sign-in. Write a short PLAN.md with the data model, screens, third-party services and what you are leaving out of version one. 2. Build the core loop end to end before anything else: give every pound or dollar a job, working with real data saved to the database. 3. Add the rest of the features one at a time, and seed realistic demo data so every screen looks alive. 4. Keep API keys in environment variables, and put any paid service behind a small interface with a local stub, so the app runs on a fresh machine without accounts. 5. Run it, click through every screen on desktop and mobile widths, fix what breaks, and finish with a summary of what works, what is stubbed and how to deploy it.
Paste it into Claude Code in an empty folder. It plans first, so read PLAN.md and steer before it starts building.
Version one
- Give every pound or dollar a job
- Category budgets that roll over
- Transaction entry and import
- Goals per category
- Spending reports
The hard part
Bank sync. Start with CSV import and add Plaid later.
Make it yours: a niche YNAB ignores, an original name and brand, and one feature it does badly done well.
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