Ask HN: Interest in FOSS tool to analyse market data?

I think something may already exist, but my brief research has found nothing. Main features of the tool:

1) be completely offline as for processing, support multiple sources of market data 2) work according to the unix philosophy of small interoperable parts that work standalone (i.e. in a Jupyter notebook) 3) be free as in beer

I'm currently and slowly building it for my own enjoyment but the plan is to open it as soon as a decent subset of features is available.

Would you use/contribute to it or are things such as tradingview/ad hoc notebooks enough?