Adding a file to a package

I am aware, that the casual way to add a file to an existing package, would be to override or create an overlay.

Both options seem overly complicated, compared to the simple process it used to be for me on other distros.

Is there maybe some third party tool, or something else, that helps me doing this more painless?

Concrete: I like to add a custom syntax highlighter to Kate. :slight_smile: