Show HN: BudgetFlow – Plan your budget as an interactive Sankey diagram

I posted BudgetFlow here two years ago and got around a hundred comments of feedback. I have kept working on it since then, and this is what changed:

- A complete overhaul to simplify how budgets are built based on user feedback

- Step by step tutorials that build example budgets

- Retirement planner using Monte Carlo simulations

- Split expenses: track shared costs in a group and settle up

The tech stack is pretty minimalistic, it is a Flask app with htmx and SQLite on a single small server.

I would like to hear from you what could be improved, and happy to answer any questions about how it is built!