eudev : Linux dynamic and persistent device naming support (aka userspace devfs) ( https://github.com/eudev-project/eudev )
libudev-zero : Drop-in replacement for libudev intended to work with any device manager ( https://github.com/illiliti/libudev-zero )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a without-systemd
For Paludis use this rsync : rsync://gentoo.zugaina.org/without-systemd-portage
If you have a problem : ycarus(-at-)zugaina.org