I built the finance app I wanted for myself. It works in English and Spanish and covers envelope budgets, investments, giving and a few currencies.
What it does
- A dashboard with my balance, monthly spending and how both have changed
- Envelope budgeting, with a progress bar for each pool
- Movements, with the full history and a calendar you can click into
- Investments and net worth, shown next to day-to-day spending
- Imports from CSV inside the app, plus Santander statements
- Multiple currencies: 20 of them, converted against EUR
- Spending charts by category, built with Recharts
Build notes
It runs on Next.js 16 with React Server Components, Supabase for auth and Postgres with row-level security, Tailwind CSS v4 and Base UI. The design uses soft neutrals and tabular-nums on every number, with green when a figure goes up and rose when it goes down. On a phone you get a bottom nav, and on desktop a sidebar.
Status
It's live and I keep adding to it. The most recent additions are the calendar, transfers, net worth and CSV import.