I don't plan to make a version that gets its data from local man pages, but it would be great if such a tool existed.

Parsing the data out of man pages is messy, and my process currently involves a lot of steps. I actually only started collecting the data for this as a side-effect of trying to make man pages render nicely in browsers.

I would like to open source more of the backend, but I've started with a tool I wrote to extract man pages from project repos: https://github.com/jacksonp/manlib