anchor.diff:            if [ "$(readlink -f $i/$fn)" = /dev/null ]; then
               ln -sfn /dev/null $out/$fn
             else
  -            mkdir $out/$fn.d
  +            mkdir -p $out/$fn.d
               ln -s $i/$fn $out/$fn.d/overrides.conf
             fi
          else
  
positive.code:       for i in ${toString cfg.packages}; do
          for fn in $i/etc/systemd/${type}/* $i/lib/systemd/${type}/*; do
            if ! [[ "$fn" =~ .wants$ ]]; then
              ln -s $fn $out/
            fi
          done
        done
  
negative.code: 
  with lib;
  
  let
    cfg = config.systemd;
    lndir = "${pkgs.xorg.lndir}/bin/lndir";
  in rec {
  
    shellEscape = s: (replaceChars [ "\\" ] [ "\\\\" ] s);
  
  