The problem with spreadsheets is generally maintainability and testing not performance. At least if it is slow people might rewrite it on a better platform.

I am sure there is a market though.

We're hoping that better performance will let users build well-designed spreadsheets - they'll be able to show more steps and use less archaic formulas without having to worry about slowdowns.

If you can speed up serious financial sector spreadsheets - hideous baroque constructions of formulae and VBA - they will pay you any amount of money for this.

How are you accelerating Excel so much, in a way that Microsoft wouldn't have thought about? No trashing, I'm just curious, and the website doesn't tell much apart from "demolishing the bottlenecks".

We wrote a static optimizer for spreadsheets - this looks at the entire sheet and reduces computational complexity where it can.

Excel's built-in functions are optimized to run fast individually, not to work in concert. (Also, some of them are just slow for no good reason.)

That's an interesting approach, thank you!