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Vida a Dois

In progress

A personal finance ERP for people who share the bills.

2026Next.jsTypeScriptPrismaPostgreSQLAuth.jsStripe
See it livePrivate repository

Overview

An early-stage project. The idea is a finance ERP for individuals, couples and families that answers what an expense tracker can't: how much of the month is already committed, what's really left, and how long the household holds up if one income stops. The foundation works and is live, but it's still a personal project with no launch — and it's also where I'm trying out, at small scale, a development flow driven by AI agents (task loop, specs and TDD).

The idea

An expense app records what has already gone out. What people sharing a home are missing is what's still to come: next month's subscription, the sixth instalment, the card bill closing next week. Vida a Dois keeps the rule (the recurrence), the forecast (the month's entry) and the actual payment apart — only the payment touches the balance — and that separation is what lets it project cash flow instead of just recording it.

Screens

Captured from the running product.

The landing page: a finance ERP for shared life, with the same numbers for both people.
The landing page: a finance ERP for shared life, with the same numbers for both people.
The month's dashboard: current and projected balance, paid versus forecast income and expenses, and what's due next.
The month's dashboard: current and projected balance, paid versus forecast income and expenses, and what's due next.
Recurrences: each rule generates the month's forecasts, and a forecast only becomes balance once the payment is recorded.
Recurrences: each rule generates the month's forecasts, and a forecast only becomes balance once the payment is recorded.
The card treated as an account: available limit, the open cycle and the entries that will make up the next bill.
The card treated as an account: available limit, the open cycle and the entries that will make up the next bill.
Financial calendar with the month's due dates, money in green and money out in red.
Financial calendar with the month's due dates, money in green and money out in red.
Goals with progress, deadline and what's left — a contribution records progress without touching account balances.
Goals with progress, deadline and what's left — a contribution records progress without touching account balances.

Modules

Financial group

Individual, couple or family, with member invitations and multi-tenant isolation per group.

What it's for

Lets both people see the same numbers at the same time, without a shared spreadsheet.

Recurrences and forecasts

Monthly rules that generate forecasts; payment is recorded separately and is the only thing that moves the balance.

What it's for

Tells you the end-of-month balance before the month is over.

Instalment plans

Instalment purchases and loans, with early payment, discounts, surcharges and instalment adjustments.

What it's for

Shows instalment debt in full, not just this month's instalment.

Card as an account

Open cycle, bill closing, reconciliation against the bank's real amount (including via OFX) and a single payment.

What it's for

Makes the available limit discount what's already committed, and the bill agree with the bank.

Dashboard, calendar and goals

Current and projected balance, spending by category, the month's due dates and goals with contributions.

What it's for

Answers "how are we doing this month?" on a single screen.

Progress

6/9 modules delivered
  1. Multi-tenant foundation — users, financial group, plans and invitationsDelivered · 2026-07
  2. Accounts, categories, income, and one-off, recurring and instalment expensesDelivered · 2026-07
  3. Dashboard, calendar, reports, goals and notificationsDelivered · 2026-07
  4. Instalment rework — loans, early payment, discounts and adjustmentsDelivered · 2026-07
  5. Card as an account — cycle, bill, OFX reconciliation and single paymentDelivered · 2026-09
  6. Railway deploy, with forecast and bill-closing cronsDelivered · 2026-09
  7. Bill ↔ instalments — lock edits to entries already billedIn progress
  8. Early instalment payment and overdue handling on cardsPlanned
  9. AI: categorisation, anomalies, monthly summary and cash-flow projectionPlanned

Stack

  • Next.js
  • TypeScript
  • Tailwind
  • shadcn/ui
  • Prisma
  • PostgreSQL
  • Auth.js
  • Stripe
  • Vitest
  • Playwright
  • Railway

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