{pkgs, ...}: {
  system = {
    # activationScripts are executed every time you boot the system or run `nixos-rebuild` / `darwin-rebuild`.
    activationScripts.postUserActivation.text = ''
      # activateSettings -u will reload the settings from the database and apply them to the current session,
      # so we do not need to logout and login again to make the changes take effect.
      /System/Library/PrivateFrameworks/SystemAdministration.framework/Resources/activateSettings -u
    '';

    defaults = {
      menuExtraClock.Show24Hour = true; # show 24 hour clock

      # customize dock
      dock = {
        autohide = true;
        #   show-recents = false;  # disable recent apps

        #   # customize Hot Corners
        #   wvous-tl-corner = 2;  # top-left - Mission Control
        #   wvous-tr-corner = 13;  # top-right - Lock Screen
        #   wvous-bl-corner = 3;  # bottom-left - Application Windows
        #   wvous-br-corner = 4;  # bottom-right - Desktop
      };

      # # customize finder
      finder = {
        _FXShowPosixPathInTitle = true; # show full path in finder title
        AppleShowAllExtensions = true; # show all file extensions
        FXEnableExtensionChangeWarning = false; # disable warning when changing file extension
        QuitMenuItem = true; # enable quit menu item
        ShowPathbar = true; # show path bar
        ShowStatusBar = true; # show status bar
      };

      # # customize trackpad
      # trackpad = {
      #   Clicking = true;  # enable tap to click
      #   TrackpadRightClick = true;  # enable two finger right click
      #   TrackpadThreeFingerDrag = true;  # enable three finger drag
      # };

      # # customize settings that not supported by nix-darwin directly
      # # Incomplete list of macOS `defaults` commands :
      # #   https://github.com/yannbertrand/macos-defaults
      # NSGlobalDomain = {
      #   # `defaults read NSGlobalDomain "xxx"`
      #   "com.apple.swipescrolldirection" = true;  # enable natural scrolling(default to true)
      #   "com.apple.sound.beep.feedback" = 0;  # disable beep sound when pressing volume up/down key
      #   AppleInterfaceStyle = "Dark";  # dark mode
      #   AppleKeyboardUIMode = 3;  # Mode 3 enables full keyboard control.
      #   ApplePressAndHoldEnabled = true;  # enable press and hold

      #   # If you press and hold certain keyboard keys when in a text area, the key’s character begins to repeat.
      #   # This is very useful for vim users, they use `hjkl` to move cursor.
      #   # sets how long it takes before it starts repeating.
      # InitialKeyRepeat = 15; # normal minimum is 15 (225 ms), maximum is 120 (1800 ms)
      #   # sets how fast it repeats once it starts.
      # KeyRepeat = 3; # normal minimum is 2 (30 ms), maximum is 120 (1800 ms)

      #   NSAutomaticCapitalizationEnabled = false;  # disable auto capitalization
      #   NSAutomaticDashSubstitutionEnabled = false;  # disable auto dash substitution
      #   NSAutomaticPeriodSubstitutionEnabled = false;  # disable auto period substitution
      #   NSAutomaticQuoteSubstitutionEnabled = false;  # disable auto quote substitution
      #   NSAutomaticSpellingCorrectionEnabled = false;  # disable auto spelling correction
      #   NSNavPanelExpandedStateForSaveMode = true;  # expand save panel by default
      #   NSNavPanelExpandedStateForSaveMode2 = true;
      # };

      # # Customize settings that not supported by nix-darwin directly
      # # see the source code of this project to get more undocumented options:
      # #    https://github.com/rgcr/m-cli
      # #
      # # All custom entries can be found by running `defaults read` command.
      # # or `defaults read xxx` to read a specific domain.
      # CustomUserPreferences = {
      #   ".GlobalPreferences" = {
      #     # automatically switch to a new space when switching to the application
      #     AppleSpacesSwitchOnActivate = true;
      #   };
      #   NSGlobalDomain = {
      #     # Add a context menu item for showing the Web Inspector in web views
      #     WebKitDeveloperExtras = true;
      #   };
      #   "com.apple.finder" = {
      #     ShowExternalHardDrivesOnDesktop = true;
      #     ShowHardDrivesOnDesktop = true;
      #     ShowMountedServersOnDesktop = true;
      #     ShowRemovableMediaOnDesktop = true;
      #     _FXSortFoldersFirst = true;
      #     # When performing a search, search the current folder by default
      #     FXDefaultSearchScope = "SCcf";
      #   };
      #   "com.apple.desktopservices" = {
      #     # Avoid creating .DS_Store files on network or USB volumes
      #     DSDontWriteNetworkStores = true;
      #     DSDontWriteUSBStores = true;
      #   };
      #   "com.apple.spaces" = {
      #     "spans-displays" = 0; # Display have seperate spaces
      #   };
      #   "com.apple.WindowManager" = {
      #     EnableStandardClickToShowDesktop = 0; # Click wallpaper to reveal desktop
      #     StandardHideDesktopIcons = 0; # Show items on desktop
      #     HideDesktop = 0; # Do not hide items on desktop & stage manager
      #     StageManagerHideWidgets = 0;
      #     StandardHideWidgets = 0;
      #   };
      #   "com.apple.screensaver" = {
      #     # Require password immediately after sleep or screen saver begins
      #     askForPassword = 1;
      #     askForPasswordDelay = 0;
      #   };
      #   "com.apple.screencapture" = {
      #     location = "~/Desktop";
      #     type = "png";
      #   };
      #   "com.apple.AdLib" = {
      #     allowApplePersonalizedAdvertising = false;
      #   };
      #   # Prevent Photos from opening automatically when devices are plugged in
      #   "com.apple.ImageCapture".disableHotPlug = true;
      # };

      # loginwindow = {
      #   GuestEnabled = false;  # disable guest user
      #   SHOWFULLNAME = true;  # show full name in login window
      # };
    };

    # keyboard settings is not very useful on macOS
    # the most important thing is to remap option key to alt key globally,
    # but it's not supported by macOS yet.
    # keyboard = {
    #   enableKeyMapping = true;  # enable key mapping so that we can use `option` as `control`

    #   # NOTE: do NOT support remap capslock to both control and escape at the same time
    #   remapCapsLockToControl = false;  # remap caps lock to control, useful for emac users
    # remapCapsLockToEscape = true; # remap caps lock to escape, useful for vim users

    #   # swap left command and left alt
    #   # so it matches common keyboard layout: `ctrl | command | alt`
    #   #
    #   # disabled, caused only problems!
    #   swapLeftCommandAndLeftAlt = false;
    # };
  };

  # Add ability to used TouchID for sudo authentication
  security.pam.enableSudoTouchIdAuth = true;

  # Create /etc/zshrc that loads the nix-darwin environment.
  # this is required if you want to use darwin's default shell - zsh
  programs.zsh.enable = true;
  environment.shells = [
    pkgs.zsh
    pkgs.fish
    pkgs.bash
  ];

  # Set your time zone.
  time.timeZone = "America/Detroit";
}