anchor.diff:  
         cacheNetworks = mkOption {
           default = ["127.0.0.0/24"];
  +        type = types.listOf types.str;
           description = "
             What networks are allowed to use us as a resolver.  Note
             that this is for recursive queries -- all networks are
  
positive.code: 
        zones = mkOption {
          default = [];
          description = "
            List of zones we claim authority over.
              master=false means slave server; slaves means addresses
             who may request zone transfer.
          ";
          example = [{
            name = "example.com";
  
negative.code: 
        forwarders = mkOption {
          default = config.networking.nameservers;
          type = types.listOf types.str;
          description = "
            List of servers we should forward requests to.
          ";
  