Add support for darwin

machines/demeter/configuration.nix

@@ -0,0 +1,59 @@
+{ pkgs, ... }:
+
+{
+  imports = [ <home-manager/nix-darwin> ];
+
+  nixpkgs.config.allowUnfree = true;
+
+  environment = { variables = { LANG = "en_US.UTF-8"; }; };
+
+  networking = { hostName = "demeter"; };
+
+  system.defaults = {
+    NSGlobalDomain = {
+      AppleMeasurementUnits = "Centimeters";
+      AppleMetricUnits = 1;
+      AppleShowScrollBars = "Automatic";
+      AppleTemperatureUnit = "Celsius";
+      AppleKeyboardUIMode = 3;
+      ApplePressAndHoldEnabled = false;
+      InitialKeyRepeat = 10;
+      KeyRepeat = 3;
+      _HIHideMenuBar = true;
+    };
+
+    dock = {
+      autohide = true;
+      mru-spaces = false;
+      tilesize = 512;
+    };
+
+    finder = {
+      AppleShowAllExtensions = true;
+      QuitMenuItem = true;
+      FXEnableExtensionChangeWarning = false;
+    };
+
+    trackpad = {
+      Clicking = true;
+      TrackpadThreeFingerDrag = true;
+      TrackpadRightClick = true;
+    };
+
+    # Login and lock screen
+    loginwindow = { GuestEnabled = false; };
+  };
+
+  # Auto upgrade nix package and the daemon service.
+  services.nix-daemon.enable = true;
+  nix.package = pkgs.nixFlakes;
+
+  programs.zsh = {
+    enable = true;
+    # https://github.com/nix-community/home-manager/issues/108#issuecomment-340397178
+    enableCompletion = false;
+  };
+
+  # Used for backwards compatibility, please read the changelog before changing.
+  system.stateVersion = 4;
+}