mokelly on HN Glance

These guys have a similar concept. Except they really only seek to estimate materials quantities.

I have used their xml files previously to automatically tile roofs with solar panels.

State charts can be a powerful method for rapid prototyping of embedded systems if you use a minimalist code generation tool like Quantum Leaps QM.

It is a little difficult to get a hang of, but with familiarity it greatly increases the speed at which I can iterate on designs.

Note: I am not affiliated with Quantum Leaps, but I have found the tools to be very useful.