Rust was chosen as a modeling language for two reasons:

1. Since the whole project is written in Rust, it was the most straight-forward choice. No dealing with bindings to another language or a scripting language runtime for the time being. 2. To provide an interesting alternative. I suspect that there can be a nice niche for Rust, creating infrastructure for writing models (e.g. libraries for generating screw threads, that kind of stuff).

I don't think that Rust is a great language for defining CAD models. Long-term, I suspect that the preferred choice for Fornjot will be something else. But for the time being, this decision allows me to focus on the CAD kernel.

> There also seems to be a goal overlap between Fornjot and DieselCAD

Do you have a link for DieselCAD? Searching on Google only got me car results.