  Providing users of HPC systems with a wide variety of up to date software
packages is a challenging task. Large software stacks built from source are
difficult to manage, requiring powerful package management tools. The Portage
package manager from Gentoo is a highly flexible tool that offers a mature
solution to this otherwise daunting task. The Gentoo Prefix project develops
and maintains a way of installing Gentoo systems in non-standard locations,
bringing the virtues of Gentoo to other operating systems. Here we demonstrate
how a Gentoo Prefix installation can be used to cross compile software packages
for the Intel Xeon Phi known as Knights Corner, as well as to manage large
software stacks in HPC environments.
