anchor.diff:  
       environment.etc = singleton
         { # Friendly greeting on the virtual consoles.
  -        source = issueFile;
  +        source = pkgs.writeText "issue" ''
  +
  +          [1;32m${config.services.mingetty.greetingLine}[0m
  +          ${config.services.mingetty.helpLine}
  +
  +        '';
           target = "issue";
         };
   
  
positive.code:         # instead, to ensure that login terminates cleanly.
          KillSignal=SIGHUP
        '';
  
      boot.systemd.units."serial-getty@.service".text =
        ''
          [Unit]
  
negative.code: { config, pkgs, ... }:
  
  with pkgs.lib;
  
  {
  
  