interfaces and package config externalized, also tmux added and version variable

configuration.nix

@@ -17,6 +17,7 @@
       ./users.nix
       ./program-homemanager.nix
       ./ssh.nix
+      ./program-tmux.nix
 
       # Hardware
       ./nfs-mount.nix
@@ -46,18 +47,19 @@
   networking.hostName = config.vars.hostname; # Define your hostname.
   networking.hostId = config.vars.hostid; # Define your hostID - Needs to be unique!.
   networking = {
-    interfaces.enp1s0 = {
+    interfaces.${lib.head config.vars.interfaces} = {
       ipv4.addresses = [{
         address = config.vars.local_ip;
         prefixLength = 24;
       }];
     };
-    defaultGateway = {
-      address = "192.168.178.1";
-      interface = "enp1s0";
-    };
-    nameservers = [ "192.168.178.10" "9.9.9.9" ];
   };
+  networking.defaultGateway = {
+    address = "192.168.178.1";
+    interface = lib.head config.vars.interfaces;
+  };
+  networking.nameservers = [ "192.168.178.10" "9.9.9.9" ];
+
 
   # Set your time zone.
   time.timeZone = "Europe/Berlin";
@@ -88,12 +90,10 @@
   # List packages installed in system profile. To search, run:
   # $ nix search wget
   environment.systemPackages = with pkgs; [
-  #   vim # Do not forget to add an editor to edit configuration.nix! The Nano editor is also installed by default.
     wget
     htop
     ncdu
     git
-    tmux
     zsh
     zoxide
     fzf
@@ -103,11 +103,6 @@
     seaweedfs
   ];
 
-  programs.tmux = {
-    enable = true;
-    clock24 = true;
-  };
-
   # Open ports in the firewall.
   # networking.firewall.allowedTCPPorts = [ ... ];
   # networking.firewall.allowedUDPPorts = [ ... ];