Okay, here's what I learned:

* except for source code, the modules itself in Guile aren't very
* detailed documented. The documentation is good, but...  ... it's
* nowhere mentioned that you can have a module (foo bar baz) and
* possibly also (foo bar baz kim) but (foo baz bar bar) will lead to
* the error I described.

So until I read into the core of Guile, I have 2 questions:

1. Is there a module name maximum length? -> So far I have encountered
very short module names in the wild, 3 the longest.

2. Is this really a module length problem? -> I have a functional set
of packages elsewhere, my non-core packages, named like (ports editors
foo foo) and so forth and they cause no problems. It's just weird to
me that the modules in ports and elsewhere work but in pkgs I can't
dissect the exact problem so far. I'm okay with any namespace, so
I'll simply remove the last element of the module names.

I'd like to improve documentations or other relevant places if
what I experienced is some kind of corner case in module naming,
be it in Guix or Guile... or just to note what to avoid with
regards to modules.