AppStream

AppStream is a cross-distribution effort for enhancing the way we interact with the software repositories provided by (Linux) distributions by standardizing software component metadata.

It provides the foundation to build software-center applications, by providing metadata necessary for an application-centric view on package repositories. AppStream additionally provides specifications for things like an unified software metadata database, screenshot services and various other things needed to create user-friendly application-centers for (Linux) distributions.

What AppStream Offers

• Specifications & Standards: Describes the XML-based MetaInfo files for use by upstream projects, as well as AppStream catalog metadata in XML or YAML for use by repository providers.
• Reference Implementation: Provides GLib/GObject libraries for easy manipulation of metadata, with features for quick metadata indexing, querying and system compatibility checks. A Qt interface and other language bindings are provided as well.
• Tools: Includes appstreamcli for metadata queries, data verification and diagnostics. The appstreamcli compose tool can be used for simple catalog metadata composition.