How to configure a printer on Guix System

[Christophe Pisteur]

Hello,

I don't understand how to configure a printer on Guix System. 

I should configure the print service, as explain in the manual section
8.8.6, but I don't understand the procedure. I would probably need a
"how to".

Since now, I installed the following packages: cups, cups-filters,
fomatics-filters.

When I launch http: // localhost: 631 / in my browser, I receive this
information:
IceCat can’t establish a connection to the server at localhost: 631.


I want to install a Ricoh MPC 3003 printer with a ppd included in
openprinting.org:
https://www.openprinting.org/printer/Ricoh/Ricoh-MP_C3003
(MIT license)
It works on debian.

Thank you for your help.

Christophe