0release is a program to generate source and binary releases automatically. With minimal configuration, 0release will generate a source tarball release candidate, build it to create a binary archive, upload them to your Web server, check the uploads, and tag the release in GIT and update the version number. It can run unit-tests and custom actions, such as building documentation, etc. For Zero Install users, it can also upload a signed XML metadata file about the release, allowing these users to upgrade automatically. Releases are signed with your GPG key.
Graft provides a mechanism for managing multiple packages under a single directory hierarchy. It was inspired by both Depot (from Carnegie Mellon University) and Stow (by Bob Glickstein). Packages are installed in self-contained directory trees and symbolic links from a common area are made to the package files.
Yum (Yellow dog Updater, Modified) is an automatic updater and package installer/remover for RPM systems. It automatically computes dependencies and figures out what things should occur to install packages. It makes it easier to maintain groups of machines without having to manually update each one using rpm.
spill manages symbolic links under one tree which point to matching filenames in another. When individual projects are configured with project/version-specific -- prefix= settings, to keep their installations segregated, spill can make them appear to be installed in a common place, e.g. under /usr/local. It can also delete the links associated with a particular program. It is similar in concept to various other programs such as stow, depot, and relink. However, it's written in C, so it isn't reliant on an interpreter being available. It also doesn't assume complete control of the directory tree where the symbolic links are created. It can create both absolute or relative symbolic links, the latter being more convenient in some setups.
tidy-cache is a plugin for YUM, a software management system found in many Linux distributions. It helps to minimize the size of YUM's cache directory by deleting RPM packages files if newer versions of the same package are also present in the cache. You can exclude specific packages from being tested and you can set the number of old versions to keep in the cache.
tidy-rpm-cache.py is a Python script that removes RPM package files from a cache (i.e. a collection of directories) if a newer version of that package exists. It may be useful if you wish to minimize the disk space used by locally stored update packages. You can specify any number of paths of directories to search, and you can also exclude specific packages from being tested for obsolescence.