partial guix pack?

[Andy Tai]

Can a guix pack be partial?  By that I meant one package that is not
completely stand alone but only contains a subset of needed software,
bundled libraries.  for example, one that bundles specific version of
gtk+ but not glibc?  Of course such a package depends on host glibc
and may have the risk of breakage but it is likely low risk if the
main problem is it needs specific version of gtk+.