Zero Install is a decentralised cross-distribution software installation system available under the LGPL. It allows software developers to publish programs directly from their own web-sites, while supporting features familiar from centralised distribution repositories such as shared libraries, automatic updates and digital signatures. It is intended to complement, rather than replace, the operating system's package management. 0install packages never interfere with those provided by the distribution. 0install does not define a new packaging format; unmodified tarballs or zip archives can be used. Instead, it defines an XML metadata format to describe these packages and the dependencies between them. A single metadata file can be used on multiple platforms (e.g. Ubuntu, Debian, Fedora, openSUSE, Mac OS X and Windows), assuming binary or source archives are available that work on those systems.