You can either
git clone https://github.com/atheme/atheme.git or download the most recent tarball from our website. Do not use the Download buttons on GitHub, as GitHub's automatically generated tarballs do not contain all needed submodules, etc. for Atheme to correctly build.
Building from the Git Repository
If you have checked out the Atheme Git repository, before building you must run the following command in order to load all submodules required to build:
Building from release tarballs
If you have obtained Atheme through a release tarball, no extra steps are required before building. If you receive
error: please read GIT-Access.txt before trying to build from git when attempting to build, please ensure you have downloaded the correct source archive.
You must use the tarball labelled
atheme-7.x.x attached to each release, or the tarball obtained directly through atheme.org. Do not use the "Source code" links supplied by GitHub, as they're missing submodules.