I’ll have to check out both OpenSCAD and Code Comic. Some completely non-CAD DSLs that you might be interested in, since you mentioned GraphViz:

Mermaid.js does something very similar to Graphviz. There are a couple other similar tools like that out there, but Mermaid is supported in a lot of places natively or as an easy to use plugin, like GitHub Markdown (and other git forges like Forgejo), Hedgedoc, Obsidian, SilverBullet, etc…

I’d also argue that LaTeX counts, and to a lesser extent, Markdown - compare using them to using Word.

And reveal.js is an equivalent for slide deck creation that would normally be done with PowerPoint.