Setting up layman and dlang overlay
1) Emerge layman package, configure portage to use it:
emerge layman echo "source /usr/portage/local/layman/make.conf" >> /etc/make.conf
If you have different directory where layman data is stored, you should modify this command respectively;
2) Edit /etc/layman/layman.cfg and append http://svn.dsource.org/projects/gentoo/trunk/layman.xml to overlays variable;
3) Fetch overlays list and add dlang overlay:
layman -f layman -a dlang
After this you can upgrade the overlay with this simple command:
layman -s dlang