ostree : Operating system and container binary deployment and upgrades ( https://ostree.readthedocs.io/en/latest/ )
packer : A tool to create identical machine images for multiple platforms ( https://www.packer.io )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a defiance
For Paludis use this rsync : rsync://gentoo.zugaina.org/defiance-portage
If you have a problem : ycarus(-at-)zugaina.org