text: { config, lib, pkgs, ... }:
  
  with lib;
  
  let
    cfg = config.networking.iproute2;
  in
  {
    options.networking.iproute2 = {
      enable = mkEnableOption "copy IP route configuration files";
      rttablesExtraConfig = mkOption {
        type = types.lines;
        default = "";
        description = ''
          Verbatim lines to add to /etc/iproute2/rt_tables
        '';
      };
    };
  
    config = mkIf cfg.enable {
      environment.etc."iproute2/bpf_pinning" = { mode = "0644"; text = fileContents "${pkgs.iproute}/etc/iproute2/bpf_pinning"; };
      environment.etc."iproute2/ematch_map"  = { mode = "0644"; text = fileContents "${pkgs.iproute}/etc/iproute2/ematch_map";  };
      environment.etc."iproute2/group"       = { mode = "0644"; text = fileContents "${pkgs.iproute}/etc/iproute2/group";       };
      environment.etc."iproute2/nl_protos"   = { mode = "0644"; text = fileContents "${pkgs.iproute}/etc/iproute2/nl_protos";   };
      environment.etc."iproute2/rt_dsfield"  = { mode = "0644"; text = fileContents "${pkgs.iproute}/etc/iproute2/rt_dsfield";  };
      environment.etc."iproute2/rt_protos"   = { mode = "0644"; text = fileContents "${pkgs.iproute}/etc/iproute2/rt_protos";   };
      environment.etc."iproute2/rt_realms"   = { mode = "0644"; text = fileContents "${pkgs.iproute}/etc/iproute2/rt_realms";   };
      environment.etc."iproute2/rt_scopes"   = { mode = "0644"; text = fileContents "${pkgs.iproute}/etc/iproute2/rt_scopes";   };
      environment.etc."iproute2/rt_tables"   = { mode = "0644"; text = (fileContents "${pkgs.iproute}/etc/iproute2/rt_tables")
                                                                     + (optionalString (cfg.rttablesExtraConfig != "") "\n\n${cfg.rttablesExtraConfig}"); };
    };
  }
  