anchor.diff:          startOn = ["startup" "new-devices"];
   
           script =
  -          ''        
  -            swapDevices=${toString (map toPath config.swapDevices)}
  -          
  -            for device in $swapDevices; do
  -                ${utillinux}/sbin/swapon "$device" || true
  -            done
  +          ''
  +            ${toString (map (x: x.command) config.swapDevices)}
   
               # Remove swap devices not listed in swapDevices.
               for used in $(cat /proc/swaps | grep '^/' | sed 's/ .*//'); do
  
positive.code: 
        type = types.list types.optionSet;
  
        options = {
  
          device = mkOption {
            default = null;
            example = "/dev/sda3";
            type = types.nullOr types.string;
            description = ''
              Path of the device.
            '';
          };
  
          label = mkOption {
            default = null;
            example = "swap";
            type = types.nullOr types.string;
            description = "
              Label of the device.  Can be used instead of <varname>device</varname>.
            ";
          };
  
        };
  
negative.code: 
  let
  
    inherit (pkgs) cryptsetup utillinux;
  
  in
  
  {
  