migrate most of the nixos system

modules/system/base.nix

@@ -0,0 +1,25 @@
+{ hostname, timezone, ... }: {
+  system.stateVersion = "24.11";
+  imports = [ ./apps.nix ];
+
+  nixpkgs.config.allowUnfree = true;
+  nix = {
+    settings = {
+      experimental-features = [ "nix-command" "flakes" ];
+      auto-optimise-store = true;
+    };
+    gc = {
+      automatic = true;
+      dates = "weekly";
+      options = "--delete-older-than 7d -d";
+    };
+    optimise.automatic = true;
+  };
+
+  networking.hostName = "${hostname}";
+  time.timeZone = timezone;
+  services = {
+    openssh.enable = true;
+    tailscale.enable = true;
+  };
+}