Thank you for the github and Slim tips.
Slim actually worked, for future readers, this is the (services ...)
configuration that worked for me.
(services
(cons* (service gnome-desktop-service-type)
(service openssh-service-type)
(set-xorg-configuration
(xorg-configuration
(keyboard-layout keyboard-layout))
slim-service-type)
(service slim-service-type (slim-configuration
(auto-login? #t)
(default-user "username")))
(remove (lambda (service)
(eq? (service-kind service) gdm-service-type))
%desktop-services)))
Yes, you can't logout and login again as different user... But my other
user is there mainly through ssh so, it is not really a problem.
Best Regards,
--
E. Seuret