Hi HN. Modeleon is an open-source Python DSL for financial models.
You write models in Python with named variables and operator-overloaded
arithmetic, and it compiles to a real .xlsx with live formulas — not
values, but formulas like =B4*B5 that the CFO can audit in Excel.
The architectural bet is "model is the source of truth, spreadsheet is one rendering." We have a Walker/Renderer split so the same model can target Excel today and other backends later.
We've been building this for finance + Python developers (CFA candidates with Python skills, FP&A analysts who automate). It's pre-alpha — works, but the API will change before 1.0.
Apache 2.0. PyPI: pip install modeleon. Happy to answer questions.