fuse-archive : Read-only FUSE file system for mounting archives and compressed files ( https://github.com/google/fuse-archive )
libarchive-qt : A Qt based archiving solution with libarchive backend ( https://gitlab.com/marcusbritanicus/libarchive-qt )
microtar : A lightweight tar library written in ANSI C ( https://github.com/rxi/microtar )
ouch : A cli utility for easily compressing and decompressing files and directories. ( https://github.com/ouch-org/ouch )
unalz : Extract ALZ archives ( http://kippler.com/win/unalz/ )
zarchive : Library for creating and reading zstd-compressed file archives (.zar) ( https://github.com/Exzap/ZArchive )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a guru
For Paludis use this rsync : rsync://gentoo.zugaina.org/guru-portage
If you have a problem : ycarus(-at-)zugaina.org