SLOTH is not aimed to reinvent the wheel but to make use of already developed tools and to add missing methods and functions where needed.
Therefore this directory does contain / is linking to other repositories which does hold useful functionality. Those methods are then integrated within SLOTH, to most efficiently use and combine already developed tools.
External git-repositories which are stored inside another git-repository are called submodules
. So this external repositories are the reason why one have to spend a littel extra effort in cloning the SLOTH repository.