[Rexxar]

I have done a similar tool but based on geometric relations instead of constraints, you can see links in my profile (it's only on mac app store at the moment)

[buckminster]

Also Haskell Diagrams.

https://archives.haskell.org/projects.haskell.org/diagrams/

[j88439h84]

I am curious what sort of technologies and math are used in that kind of program.