Discover, KDE, upgrade

There is a “Discover” application in KDE, to upgrade applications and programs, but I can’t install it so that it works correctly with all the dependencies.
Can anyone tell me how to install KDE Discover to make it work?

discover doesn’t have a backend for nix, so you cannot use it to install applications.

It does however work fine for the various types of addons you will see inside discover.

I haven’t tested this but I suspect it would work fine to install/update flatpaks if you have support for them enabled.