How to properly package umbrella projects?

[Unstable Horse]

Hi Guix,

short question: a program I'm writing depends on gst-plugin-gtk4 which
is a part of gst-plugins-rs[0]. What's the most appropriate way to
package such a project:

1. A package just for gst-plugin-gtk4, or
2. A package for gst-plugins-rs that installs all of its subprojects?

Side note: different subprojects have different licenses.

[0]: https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs