Add openfortivpn.nix with sops secrets.

modules/core/system.nix

@@ -0,0 +1,34 @@
+{
+  pkgs,
+  username,
+  hostname,
+  modulesPath,
+  inputs,
+  ...
+}:
+{
+  boot.kernelPackages = pkgs.linuxPackages_latest;
+
+  time.timeZone = "Europe/Paris";
+
+  nix = {
+    settings = {
+      ## Enable flakes
+      experimental-features = [
+        "nix-command"
+        "flakes"
+      ];
+      ## Users trusted to use flake command
+      trusted-users = [
+        "root"
+        "${username}"
+      ];
+    };
+  };
+
+  networking = {
+    hostName = "${hostname}";
+    networkmanager.enable = true;
+    firewall.enable = true;
+  };
+}