Split everything up

system/default.nix

@@ -0,0 +1,13 @@
+{lib, ...}:
+{
+    imports = [
+        ./network.nix
+        ./users.nix
+        ./nix.nix
+        ./packages.nix
+    ];
+
+    # Internationalisation properties
+    time.timeZone = "CET";
+    i18n.defaultLocale = "en_US.UTF-8";
+}

system/network.nix

@@ -0,0 +1,16 @@
+{lib, ...}:
+{
+  networking = {
+    firewall.enable = false;
+
+    networkmanager = {
+      enable = true;
+      dns = "systemd-resolved";
+    };
+  };
+
+  services.resolved.enable = true;
+
+  # Don't wait for network manager startup
+  systemd.services.NetworkManager-wait-online.enable = lib.mkForce false;
+}

system/nix.nix

@@ -0,0 +1,35 @@
+{pkgs, ...}:
+{
+  nix = {
+    settings = {
+      # nix often takes up a lot of space, with /nix/store growing beyond reasonable sizes
+      # this turns on automatic optimisation of the nix store that will run during every build
+      # (alternatively, you can do this manually with `nix-store --optimise`)
+      auto-optimise-store = true;
+      # enable flakes support
+      experimental-features = [ "nix-command" "flakes" ];
+    };
+
+    # Enable automatic garbage collection, deleting entries older than 14 days
+    # you can also run this manually with `nix-store --gc --delete-older-than 14d`.
+    # If a result still exists in the file system, all the dependencies used to build
+    # it will be kept.
+    gc = {
+      automatic = true;
+      dates = "weekly";
+      options = "--delete-older-than 14d";
+    };
+
+    # Also run garbage colleciton whenever there is not enough space left,
+    # freeing up to 1 GiB whenever there is less than 512MiB left.
+    extraOptions = ''
+      min-free = ${toString (512 * 1024 * 1024)}
+      max-free = ${toString (1024 * 1024 * 1024)}
+    '';
+  };
+
+  nixpkgs.config.allowUnfree = true;
+
+  # Git is needed for flakes
+  environment.systemPackages = with pkgs; [git];
+}

system/packages.nix

@@ -0,0 +1,9 @@
+{pkgs, ...}:
+{
+  # Basic list of must-have packages for all systems
+  environment.systemPackages = with pkgs; [
+    vim
+    gnupg
+    delta
+  ];
+}

system/users.nix

@@ -0,0 +1,8 @@
+{pkgs, ...}:
+{
+  users.users.itsdrike = {
+    isNormalUser = true;
+    extraGroups = [ "wheel" ];
+    initialPassword = "itsdrike";
+  };
+}