https://www.freedesktop.org/software/PackageKit/index.html
https://www.freedesktop.org/software/PackageKit/pk-intro.html
https://www.freedesktop.org/software/PackageKit/pk-using.html
    pkcon get-updates
https://www.freedesktop.org/software/PackageKit/pk-faq.html

https://github.com/PackageKit/PackageKit

api
https://www.freedesktop.org/software/PackageKit/gtk-doc/api-reference.html
https://www.freedesktop.org/software/PackageKit/gtk-doc/PackageKit.html
https://www.freedesktop.org/software/PackageKit/gtk-doc/Transaction.html

https://www.freedesktop.org/software/PackageKit/pk-users.html

ui
https://store.kde.org/p/1127861