make networking setup more declarative

networks.nix

@@ -0,0 +1,21 @@
+{ config, pkgs, ... }:
+
+{
+  # Allow ipv4 port forwarding
+  boot.kernel.sysctl = { "net.ipv4.ip_forward" = 1; };
+
+  networking = {
+
+    useDHCP = false;
+    interfaces.eth0.useDHCP = false;
+    interfaces.wlan0.useDHCP = true;
+
+    interfaces.eth0.ipv4.addresses = [ {
+      address = "192.168.22.1";
+      prefixLength = 24;
+    } ];
+
+    wireless.enable = true;
+    wireless.interfaces = [ "wlan0" ];
+  };
+}