I made this by forking the existing rust CAD kernel truck and refactoring it from 60% face recovery to 99.9%. Now it's the fastest open source STEP renderer in the world by whole number multiples (at least 3x on moderately complex assemblies). Purpose built for agentic CAD.
Agentic CAD is very much bottlenecked by rendering time (as well as generation time). If you make a small change to a big model you need to reload the whole thing which can take minutes.