Creandus began as a project for Google’s Summer of Code in 2006 (proposal). It aims to provide a simple interface for package managers to manage users added for specific packages. Hooks are available for the Paludis package manager, and it is easy enough to hook into your package manager, using the Creandus API Documentation.
Creandus is an implementation of Gentoo’s GLEP 27. It is meant to replace the enewuser and enewgroup functions. While it was written for Gentoo, it would be very easy to extend it to any other distribution – the only thing it really needs is bash.
Implementing GLEP 27 will allow for a more automated approach to adding users with ebuilds in more cases. This will help the overall security of the Gentoo rise, as it will be easier for every daemon to run as its own limited user, reducing the risk of a security flaw in a daemon from causing damage to a system. Also, adding this level of automation will add a level of polish to the Gentoo distribution.
This project could be generalized to work with other package management systems in other distributions, so that they can also have dynamically-assigned UIDs/GIDs for package-specific users/groups and not have to worry about maintaining a list of officially assigned numbers.