Portage


 * A Portage Introduction
 * USE flags
 * Portage Features
 * Compilation Optimization Guide
 * Files and Directories
 * Configuring through Variables
 * Mixing Software Branches
 * Additional Portage Tools
 * Gentoolkit
 * Portage-utils

You can search by regex using:

Uncomment the package you do not want to upgrade in world at /var/lib/portage/world

Overlay

 * Gentoo Overlays: Users' Guide
 * Layman homepage
 * browse overlays that you have not installed

You can search through the ebuilds available in the overlays on http://overlays.gentoo.org/ by using eix.

Defines the directory where overlays should be installed at /var/lib/layman