* Support for multiple environments (development, staging and production)
* Support for multiple architectures (such as x86, amd64 etc.)
* Support for multiple portage build profiles
** system (or base) profile, such as desktop or server (stage3) (all the packages contained within the <code>/etc/portage/make.profile</code> or via <code>emerge @system</code>)
** application profiles, such as php5-app, django-app etc.)