I have read the holepunch stack, and even cobbled together a little NAT driller using it: https://github.com/Shinoa-Fores/hypernat. Holepunch is pretty nice all in all. Re: Keet's binary being "honest" - I can also release *parts* of the code powering something, but end-user has no guarantee there ain't a keylogger or I'm shoving metadata through a firehose back to myself. In this sense, keet is no better than zoom, skype, et all.