Not yet. I am slowly gathering resources for it, mapping out the commands, toolset and the overall UX. As well as handling the whole project management part.

I decided to exercise a bit of patience to see what other people achieve through their harnesses first (e.g. https://news.ycombinator.com/item?id=48192383, https://news.ycombinator.com/item?id=48164287).

I've chosen Rust as the language and the late summer as a deadline. If a harness is too opinionated, I don't really see the point in pushing it on anyone. And mine, I'm building it for my own workflow. So there's that

i am somebody else but my Show HN got zero engagement so please feel free to look at mine: http://github.com/0gsd/enough n.b. not a coding harness. it's for writing. but extensibility is a big (perhaps too big) part of it. http://enough.support has some of the principles outlined.