Összhang
A full-stack household finance app for budgets, shared bills, debts, savings, meter readings, and small business orders — built for families in Hungarian, with an AI coding agent as a development partner. Under continuous active development.
The Idea
Managing money at home often means spreadsheets, notes, and arguments about who paid what. I wanted one calm place where a household could see the full picture — budget, bills, debts, savings, and meters — without switching between tools.
The Approach
I split the work into a Next.js frontend on Vercel and a Laravel API on Fly.io with PostgreSQL. Auth uses Sanctum bearer tokens. I used an AI coding agent throughout development: for scaffolding modules, drafting API endpoints, refactoring, and speeding up repetitive work. I still designed the data model, chose the stack, wired deployments, and reviewed every change before shipping. The hardest parts were modeling shared utilities fairly, keeping module permissions clear per member, and making charts and monthly views feel fast on mobile.
Visual Identity
I designed a clean, trustworthy interface with clear numbers and charts. Recharts powers the dashboards. Tailwind CSS keeps layouts consistent from phone to desktop. The tone is practical and family-friendly, not corporate banking.
Art Direction
Warm, readable, and data-focused. Color highlights status (paid, due, over budget) without clutter. Hungarian copy throughout keeps it natural for the target users.
The Platform
Users register to create a household and become the first admin. The admin adds members with roles and module access — there is no invite link. Modules include Dashboard, Budget, Utilities, Debts, Savings, Meters, Business orders, and Settings. A live demo runs with test accounts so visitors can explore safely. Because development is continuous, what you see today will keep evolving — new modules and UX improvements land regularly.
The Launch
The frontend deploys on Vercel and the API on Fly.io. Every deploy seeds an Összhang Demo household with sample data. Demo logins are documented in the README so reviewers can try the app immediately. Working with an AI agent helped me move from idea to production quickly while keeping both repos structured and documented.
Current Status
Under continuous active development. The app is already live at osszhang.vercel.app with a working API and demo data, but I treat it as an evolving product — not a one-off portfolio piece. I regularly add features, refine flows, and fix edge cases, still pairing with a Cursor AI agent. The codebase is public on GitHub (frontend and backend repos).
Team & Tech Stack
I built the entire product myself and keep iterating on it, pairing with a Cursor AI agent for development. Frontend: Next.js 16, React 19, TypeScript, Tailwind CSS 4, Zustand, Recharts, dayjs. Backend: Laravel REST API, Sanctum, PostgreSQL on Fly.io.