Aegir Distributions

The Aegir Distributions module simplifies and further automates platform maintenance and site updates.

It extends the Aegir Hosting System to add a concept of "distributions":

Distributions provide site features and functions for a specific type of site as a single download containing Drupal core, contributed modules, themes, and pre-defined configuration. They make it possible to quickly set up a complex, use-specific site in fewer steps than if installing and configuring elements individually.

In Aegir terminology, a distribution is a "type" or "flavour" of platform (i. e., code-base). It could just as easily be an off-the-shelf package like OpenAtrium or Thunder, as a custom cobe-base specific to a client's use-case.