Julien Lepiller <julien@lepiller.eu> writes:

> What you need to do is to find where this package comes from:
>
>> guix package --show=libxfce4util
>
> will tell you (among other things):
>
>> location: gnu/packages/xfce.scm:81:2

Another way to find this sort of thing is to do a grep like the
following:

  grep -r 'define.*foo' ~/.config/guix/latest

I use that all the time to find service definitions, record type
definitions, syntax definitions, procedure definitions...all kinds of
definitions!

-- 
Chris