checkmate : Utility to generate and verify checksums/hashes ( https://sourceforge.net/projects/jm-checkmate/ )
sha3sum : SHA-3 and Keccak checksum utility ( https://github.com/maandree/sha3sum )
xsum : All-in-one utility to calculate and verify checksums ( https://github.com/Jannis234/xsum )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a jm-overlay
For Paludis use this rsync : rsync://gentoo.zugaina.org/jm-overlay-portage
If you have a problem : ycarus(-at-)zugaina.org