[Smaug123]

Internally to $WORK I've got a documentation system consisting of interactive F# notebooks, put together automatically from marked-up F# code (so you get type-checking while you write them) with output assertions checked in the CI pipeline for the corresponding library (and before a pipeline pushes out the latest version of the documentation). Hoping to open-source the system if I ever get time; I think Mathematica's documentation system is absolutely first-class, and I want that in any language that supports notebook-style interfaces!