Prototype
Budget Buddy
Ask ordinary finance questions of a CSV, then check the answer against the rows.
A CSV is already a system. Budget Buddy is a prototype for asking it ordinary questions in plain language, then checking the answer against the rows.
The loop is the point. A person brings a file they already trust, asks something they would otherwise do in a spreadsheet, and can see how the answer got there.
This page is the story of that prototype. It is a note, not a hosted app, and it is not financial advice.