Overview
Kakeibo is a collaborative personal finance product for individuals, households, and small teams. It helps users track accounts, income, expenses, categories, tags, attachments, reports, and shared money workflows without turning everyday budgeting into accounting software.
This is a self-directed SaaS product that I planned, designed, implemented, deployed, and maintain. The product is built around practical household finance: personal mode for individual records, team mode for shared ledgers, and paid plans for family collaboration.
Product Architecture
- Monorepo product surface - The project is organized as a pnpm monorepo with an Astro marketing website (
apps/website), a React Router v7 dashboard (apps/dashboard), a Laravel 12 API backend (apps/backend), an Expo mobile app (apps/mobile), and shared API contracts (packages/shared-api). - Static public website -
kakei.ioruns as an Astro 5 marketing site with localized public pages, legal pages, pricing, FAQ, and developer API documentation. - Authenticated dashboard -
app.kakei.iois a React Router v7 SPA using TypeScript, TailwindCSS, DaisyUI, Redux Toolkit, RTK Query, Zod, and reusable API contract packages. - Laravel API backend - The backend exposes REST APIs for accounts, transactions, categories, tags, files, teams, reports, billing, user profile, and public developer access. Sanctum handles token-based authentication.
- Mobile app surface - The Expo app uses Expo Router, NativeWind, Redux Toolkit, RTK Query, and
expo-secure-storefor mobile PAT authentication while sharing endpoint definitions with the web dashboard. - Personal and team scopes - API resources are split between
/api/v1/me/...for personal mode and/api/v1/teams/{team}/...for collaborative finance. Team context lives in the URL path, which keeps resource boundaries explicit and bookmarkable. - Immutable ledger model - Posted transaction amounts are not edited in place. Corrections are handled by voiding and appending reversal entries, while running balances are computed from ledger history.
- Public developer API - A separate
/api/public/v1namespace provides API-key based integration for paid users, isolated from the app-facing API contract. - Billing and plan gates - Laravel Cashier and Stripe power subscriptions, trial handling, checkout, billing portal, and plan gates for family/team collaboration.
Key Features
- Expense and income tracking - Record transactions with account, currency, category, date, description, tags, file attachments, and optional necessity rating.
- Household collaboration - Team mode lets couples, families, housemates, or small groups manage shared financial records with role-based access.
- Accounts and balances - Users can track multiple accounts and currencies while preserving ledger consistency across transaction history.
- Reports and analysis - Dashboard reports summarize spending totals, category distribution, and time-series trends for selected periods.
- Passwordless authentication - OTP and magic-link style login keeps onboarding lightweight across web and mobile.
- Developer access - API keys and public documentation let users connect Kakeibo data to their own tools or financial workflows.
