AppStream Compose expands the appstreamcli utility by a subcommand which allows it to construct AppStream catalog metadata from directory trees.

The tool will also perform many related metadata generation actions, like resizing icons and screenshots and merging in data from referenced desktop-entry files as well as translation status information. It provides a fast way to test how the final processed metadata for an application that is shipped to users may look like.

In addition to that, it allows to easily generate AppStream data for projects which do not need a more complex data generator like appstream-generator.