anchor.diff:  
       security.pam.loginLimits = mkOption {
         default = [];
  +      type = limitsType;
         example =
           [ { domain = "ftp";
               type   = "hard";
  
positive.code:          "${domain} ${type} ${item} ${toString value}\n")
           limits);
  
    motd = pkgs.writeText "motd" config.users.motd;
  
    makePAMService = name: service:
  
negative.code:           <varname>domain</varname>, <varname>type</varname>,
            <varname>item</varname>, and <varname>value</varname>
            attribute.  The syntax and semantics of these attributes
            must be that described in <citerefentry><refentrytitle>limits.conf</refentrytitle>
            <manvolnum>5</manvolnum></citerefentry>.
  
            Note that these limits do not apply to systemd services,
            whose limits can be changed via <option>systemd.extraConfig</option>
  