Alexander,

Alexander Asteroth 写道：
> The question now is, what is the correct guix-way to implement 
> this:

Not as complicated as you fear!

udev rules aren't special.  Just install them to the package's own 
<out>/lib/udev/rules.d directory.  If the build system tries to 
write to another package's output, see if it provides any options 
to change that, or patch it in the worst case.

> As I understand, the udev-rules are usually created on system
> level. That would mean I need to split the package into a 
> service part
> and a package part? And remove the installation of the udev-file 
> from
> the package install process?

Guix System provides a ready-made udev-rules-service to gather up 
all desired udev rules and pass them to the running udev.  I think 
this is how it works:

  (operating-system
    […]
    (services
      (cons* […]
             (udev-rules-service 'projecteur
                                 projecteur)
             %base-services)))

‘Think’ because I do it differently in my own configurations.

> Or is there another way for a package to provide the udev rules 
> from a
> user-level install? 

If this means ‘can I use Guix's udev rules on a foreign 
distribution’: I'm not sure, but not out of the box.

Kind regards,

T G-R