CUDF (for Common Upgradeability Description Format) is a format for
describing upgrade scenarios in package-based Free and Open Source
Software distribution.
In every such scenario there exists a package universe (i.e. a set
of packages) known to a package manager application, a package status
(i.e. the currently installed packages), and a user request (i.e. a
wish to change the set of installed packages) that need to be
fulfilled.
CUDF permits to describe an upgrade scenario in a way that is
both distribution-independent and package-manager-independent.
CUDF offers a rigorous semantics of dependency solving that
enables to independently check the correctness of upgrade
solutions proposed by package managers.
CUDF adoption would enable to share dependency solver components
across different package managers, both intra- and
inter-distributions.