It's very lightweight. Until I installed a WM and started a bunch of daemons, my RAM usage was not only in the megabytes, but also only double digits.
It has XBPS-SRC, which is comparable to Portage and FreeBSD Ports.
Most of the documentation is on Reddit and in blog posts, as Void Docs is quite basic and the wiki is no-longer updated. Some may consider this a good thing, others will disagree.