anchor.diff:  
   let
     cfgFile = pkgs.writeText "reader.conf" "";
  +
  +  polkitRules = "polkit-1/rules.d/50-pcscd.rules";
   in
   
   with lib;
  
positive.code:   ###### implementation
  
    config = mkIf config.services.pcscd.enable {
  
      systemd.sockets.pcscd = {
        description = "PCSC-Lite Socket";
  
negative.code:     systemd.services.pcscd = {
        description = "PCSC-Lite daemon";
        preStart = ''
          mkdir -p /var/lib/pcsc
          rm -Rf /var/lib/pcsc/drivers
          ln -s ${pkgs.ccid}/pcsc/drivers /var/lib/pcsc/
        '';
        serviceConfig = {
          Type = "forking";
  