The k42 userland 1) is based on Gentoo.

Start with a stage1 package for the architecture you want.

make.conf:

CFLAGS="-O2 -pipe"
CHOST="x86_64-linux"
CXXFLAGS="${CFLAGS}"
MAKEOPTS="-j5"

/etc/make.profile should point to /usr/portage/profiles/default-linux/amd64/2006.1/no-multilib This build pure 64-bit stuff, and not put in the gentoo-specific multilib junk.

You'll need to do a full bootstrap and

 emerge -e system 

. Don't forget to to limit your locales to speed this up (unless you want all 350+ languages).