Nixos configure a printer

Edit your /etc/nixos/configuration.nix and add the following lines :

# Enable CUPS to print documents.
  services.printing.enable = true;

 # Add drivers if necessary
  services.printing.drivers = [ pkgs.brlaser ];

 # Enable Firewall rules and network protocol for printers
  services.avahi = {
  enable = true;
  nssmdns4 = true;
  openFirewall = true;
};

After using the command nixos-rebuild switch you can now configure your printer inside cups at http://localhost:631/