Split everything up

configuration.nix

@@ -1,103 +0,0 @@
-# Edit this configuration file to define what should be installed on
-# your system.  Help is available in the configuration.nix(5) man page
-# and in the NixOS manual (accessible by running ‘nixos-help’).
-
-{ config, pkgs, ... }:
-
-{
-  imports =
-    [ # Include the results of the hardware scan.
-      ./hardware-configuration.nix
-    ];
-
-  # Bootloader.
-  boot.loader.systemd-boot.enable = true;
-  boot.loader.efi.canTouchEfiVariables = true;
-
-  networking.hostName = "nixos"; # Define your hostname.
-  # networking.wireless.enable = true;  # Enables wireless support via wpa_supplicant.
-
-  # Configure network proxy if necessary
-  # networking.proxy.default = "http://user:password@proxy:port/";
-  # networking.proxy.noProxy = "127.0.0.1,localhost,internal.domain";
-
-  # Enable networking
-  networking.networkmanager.enable = true;
-
-  # Set your time zone.
-  time.timeZone = "Europe/Bratislava";
-
-  # Select internationalisation properties.
-  i18n.defaultLocale = "en_US.UTF-8";
-
-  i18n.extraLocaleSettings = {
-    LC_ADDRESS = "sk_SK.UTF-8";
-    LC_IDENTIFICATION = "sk_SK.UTF-8";
-    LC_MEASUREMENT = "sk_SK.UTF-8";
-    LC_MONETARY = "sk_SK.UTF-8";
-    LC_NAME = "sk_SK.UTF-8";
-    LC_NUMERIC = "sk_SK.UTF-8";
-    LC_PAPER = "sk_SK.UTF-8";
-    LC_TELEPHONE = "sk_SK.UTF-8";
-    LC_TIME = "sk_SK.UTF-8";
-  };
-
-  # Configure keymap in X11
-  services.xserver = {
-    layout = "us";
-    xkbVariant = "";
-  };
-
-  # Define a user account. Don't forget to set a password with ‘passwd’.
-  users.users.itsdrike = {
-    isNormalUser = true;
-    description = "ItsDrike";
-    extraGroups = [ "networkmanager" "wheel" ];
-    packages = with pkgs; [];
-  };
-
-  # Allow unfree packages
-  nixpkgs.config.allowUnfree = true;
-
-  # List packages installed in system profile. To search, run:
-  # $ nix search wget
-  environment.systemPackages = with pkgs; [
-  vim
-  git
-  gnupg
-  delta
-  #  vim # Do not forget to add an editor to edit configuration.nix! The Nano editor is also installed by default.
-  #  wget
-  ];
-
-  # Some programs need SUID wrappers, can be configured further or are
-  # started in user sessions.
-  # programs.mtr.enable = true;
-  # programs.gnupg.agent = {
-  #   enable = true;
-  #   enableSSHSupport = true;
-  # };
-
-  # List services that you want to enable:
-
-  # Enable the OpenSSH daemon.
-  # services.openssh.enable = true;
-
-  # Open ports in the firewall.
-  # networking.firewall.allowedTCPPorts = [ ... ];
-  # networking.firewall.allowedUDPPorts = [ ... ];
-  # Or disable the firewall altogether.
-  # networking.firewall.enable = false;
-
-  # This value determines the NixOS release from which the default
-  # settings for stateful data, like file locations and database versions
-  # on your system were taken. It‘s perfectly fine and recommended to leave
-  # this value at the release version of the first install of this system.
-  # Before changing this value read the documentation for this option
-  # (e.g. man configuration.nix or on https://nixos.org/nixos/options.html).
-  system.stateVersion = "23.11"; # Did you read the comment?
-
-  nix.package = pkgs.nixUnstable;
-  nix.settings.experimental-features = [ "nix-command" "flakes" ];
-}
-

flake.nix

@@ -17,7 +17,7 @@
       flake = {
         nixosConfigurations = {
           nixos = nixpkgs.lib.nixosSystem {
-            modules = [ ./configuration.nix ];
+            modules = [ ./system ./hosts/vbox_nix ];
           };
         };
       };

hosts/vbox_nix/default.nix

@@ -0,0 +1,17 @@
+{lib, ...}:
+{
+  imports = [ ./hardware-configuration.nix ];
+
+  boot.loader = {
+    systemd-boot.enable = true;
+    efi.canTouchEfiVariables = true;
+    timeout = 3;
+  };
+
+  networking.hostName = "nixos";
+
+  # NixOS release from which this machine was first installed.
+  # (for stateful data, like file locations and db versions)
+  # Leave this alone!
+  system.stateVersion = lib.mkForce "23.11";
+}

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";
+  };
+}