It's especially weird, considering that I see Sphinx-based docs: https://github.com/joyent/libuv/tree/master/docs/src

Seems like they could at least post them in whatever state they are in. Couldn't be any worse than a directory index with some release tarballs.

If I didn't know what libuv was, I'd take one look at libuv.org and immediately look elsewhere (as silly as that is). It'd be very much worth it to get a basic page up that tosses out some links to Github and/or tutorials and stuff!