• Base chroot environment for the creation of most binary packages which will be copied to the Binary Package Server.
• Packages, which don't need to be built, for example Oracle's Java SE Development Kit (JDK), can be fetched from the Mirror Server.
• Software stacks built upon specialized binary packages, require their own chroot environment. If possible, avoid this.
• For reproducibility, Portage and Profiles are frozen with the help of version control system (git in our case). This is only done on the Mirror Server.
• When building packages in a chroot environment, the portage and overlay versions need to set.

Chroot Setup

Preparation

At least the following is required beforehand to ensure reproducible building:

• a versioned portage tree
• versioned overlays (if any)

Setup

Create a staging root and extract a stage3 or stage4 tarball: