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Math Background

Math Background is a curried functional library I created to do simple math but getting the correct result (because JavaScript doesnโ€™t).


I noticed that some WebApps that even handle money, are not using precise math for the values, son letโ€™s say that you have to pay 13.1 and you have 8.2 of taxes, the result will actually be 21.299999999999997 which is not great.


I built this library using TypeScript, with configurations from my shared configs, scaffolding it with my trusty create-package. I made it ESM only because CJS no longer made sense when I created this (Node started supporting ESM modules a long time ago), and I made it tree-shakeable by using named exports.

It took around 5 hours to be done. I started from the idea of representing numbers as a [base, exponent] tuple using bigint to ensure round long numbers, and I went from there.

I tested everything using my test library.


Iโ€™m using it now every time I want to have reliable math in my apps, you can play with it in your browser terminal by going to the reference