You will need a configuration file for the user performing the building.
Place it at ~/.config/arch_repo_builder/config.xml - you can find an example one in sample.config.xml

But it does require the following packages to be installed, and the buildbox (not the repo mirror server itself) needs to be Arch:

- pacman (duh)
- namcap
- devtools (for https://wiki.archlinux.org/index.php/DeveloperWiki:Building_in_a_clean_chroot)

It is designed to be run as a *non-root* user. Use the regen_sudoers.py script to create a sudoers CMND_ALIAS (https://www.sudo.ws/man/1.7.10/sudoers.man.html) to add for your packaging user.