mailspring-bin : The best email app for people and teams at work ( https://getmailspring.com )
mailspring-libre-bin : Fork aiming at removing Mailspring's dependecy on a central server ( https://github.com/notpushkin/Mailspring-Libre )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a menelkir
For Paludis use this rsync : rsync://gentoo.zugaina.org/menelkir-portage
If you have a problem : ycarus(-at-)zugaina.org