Personal Treasury — Finance App

I built Personal Treasury to turn a spreadsheet-based household money system into a dedicated application. It connects budget planning, cash allocation, monthly reconciliation and interaccount debts, so the user can follow a decision from the plan through the transfer and into its history. My work covers the product workflow, interface design, calculation engine, data model and desktop/browser implementation.

The workflow starts with a budget and paycheck allocation, then carries those amounts into a monthly transfer journal. Reconciliation names the checks that need attention before money is moved. Virtual account buckets stay distinct from real bank balances, while account history and debt views explain where each figure came from. The gallery shows monthly reconciliation, account history and budget planning.

I developed the interface in React and TypeScript, backed by an in-process SQLite database and a domain layer that keeps financial rules separate from the screens. Monetary calculations use decimal arithmetic and normalized decimal strings. Interaccount debts are calculated from their event history, including repayments and overpayments, rather than relying on manually edited balances.

Replacing the spreadsheet also meant preserving its meaning. Workbook imports provide previews, control totals and source-level warnings; exports and backups let the user take the data with them. Drill-through summaries, explicit reconciliation states and undo for persistent treasury edits make the application easier to inspect and correct. Calculation, database and workflow test suites support the implementation.

The product includes a downloadable Tauri desktop application for Mac and a public browser demonstration. The open source code on GitHub allows anyone to provision their own micro-server and privately host their own private treasury for secure cloud access.

The demonstration uses a fictional household; demo changes stay in the browser tab, and the gallery does not expose personal records or connected bank accounts. Personal Treasury is independently developed product work, showing how a detailed personal process can become useful custom software.

Try the fictional-data demo · Source and product documentation