[fiatjaf]

In fact it is probably all Javascript. The formula editor at the top is an Ace editor, the spreadsheet itself is based on https://github.com/openfin/fin-hypergrid, which is an incredibly enourmous piece of software I had never heard of and which I don't understand at all what it is trying to accomplish, but I can see it renders to canvas.

[zgao]

CEO of AlphaSheets here! Javascript is our frontend, but the backend is Haskell :)

[m_mueller]

So the computations are server-side? Or are you doing some Haskell-to-JS-transpiling?

[alexzhu]

Yes, the computations are all done server-side, which lets us parallelize big computations. It also keeps our thorny evaluation logic crisp and maintainable, because Haskell. =)

[sandGorgon]

what's your opinion on various spreadsheet like JS frameworks like Handsontable, Crossfilter, NxSheet and fin-hypergrid ?

As someone who has built an internal dashboard using Handsontable, I am yet to find a truly reactive JS framework for spreadsheets.

[alexzhu]

We're actually built on top of fin-hypergrid, which we chose for its speed. We're handling all the reactivity in the backend.

[fiatjaf]

What do you mean by "truly reactive" in this case?

[sandGorgon]

Formulas that get recomputed if the cells are relevant. A spreadsheet is inherently reactive.