Typescript Math Toolkit Expression Engine
I began work on this project late last year and intended to open-source an alpha in early 2016. However, a very bad car accident has shifted all my plans out four to five months. I have released a couple Angular examples in the last few months on Github, but this one is particularly interesting as it has a rather wide range of potential applications. I have used the expression engine both standalone and as a base for a lightweight, Typescript rules engine for an NDA client.
There is a good writeup on the Github repo and I know you want the code anyway, so point your friendly neighborhood browser here and have fun