{ config, pkgs, lib, ... }:
{
  nixpkgs.config.allowUnfree = true;
  # TODO: Consider adding a randomized delay.
  nix.gc = {
    automatic = true;
    dates = "weekly";
    options = "--delete-older-than 30d";
  };
  nix.settings = {
    auto-optimise-store = true;
    experimental-features = [ "nix-command" "flakes" ];
  };

  # https://datatracker.ietf.org/doc/html/rfc8375
  networking.domain = lib.mkDefault "home.arpa";

  # TODO: Consider enabling automatic-timezoned on laptops that move between TZs
  time.timeZone = lib.mkDefault "America/Chicago";
  services.automatic-timezoned.enable = lib.mkDefault false;

  i18n.defaultLocale = "en_US.UTF-8";
  i18n.extraLocaleSettings = {
    LC_ADDRESS = "en_US.UTF-8";
    LC_IDENTIFICATION = "en_US.UTF-8";
    LC_MEASUREMENT = "en_US.UTF-8";
    LC_MONETARY = "en_US.UTF-8";
    LC_NAME = "en_US.UTF-8";
    LC_NUMERIC = "en_US.UTF-8";
    LC_PAPER = "en_US.UTF-8";
    LC_TELEPHONE = "en_US.UTF-8";
    LC_TIME = "en_US.UTF-8";
  };

  console.font = null;  # Kernel will automatically choose a font.
  console.keyMap = "us";
  # 4-bit ANSI -> Catpuccin Mocha Colors: https://catppuccin.com/palette/
  console.colors = [
    "11111b"  # black               -> crust
    "f38ba8"  # red                 -> red
    "a6e3a1"  # green               -> green
    "fab387"  # yellow              -> peach
    "89b4fa"  # blue                -> blue
    "cba6f7"  # magenta             -> mauve
    "74c7ec"  # cyan                -> sapphire
    "6c7086"  # white               -> overlay 0
    "313244"  # bright black (gray) -> surface 0
    "eba0ac"  # bright red          -> maroon
    "94e2d5"  # bright green        -> teal
    "f9e2af"  # bright yellow       -> yellow
    "b4befe"  # bright blue         -> lavender
    "f5c2e7"  # bright magenta      -> pink
    "89dceb"  # bright cyan         -> sky
    "cdd6f4"  # bright white        -> text
  ];

  networking.firewall.enable = true;

  # Installed on every NixOS Host.
  environment.systemPackages = with pkgs; [
    wget curl
    ripgrep
  ];
  programs = {
    less = {
      enable = true;
      # https://ascending.wordpress.com/2011/02/11/unix-tip-make-less-more-friendly/
      # https://www.topbug.net/blog/2016/09/27/make-gnu-less-more-powerful/
      envVariables = {
        LESS = lib.concatStrings [
          "--quit-if-one-screen "
          "--ignore-case "
          "--long-prompt "
          "--raw-control-chars "  # raw ANSI colors
          "--hilite-unread "  # first unread line after forward screen
          "--tabs=4 "
          "--no-init "  # Don't use termcap init/deinit strings.
        ];
        # Render colors
        # TODO: Figure out how to represent those termcap sequences properly.
        LESS_TERMCAP_mb="\E[1;31m";     # begin bold
        LESS_TERMCAP_md="\E[1;36m";     # begin blink
        LESS_TERMCAP_me="\E[0m";        # reset bold/blink
        LESS_TERMCAP_so="\E[01;44;33m"; # begin reverse video
        LESS_TERMCAP_se="\E[0m";        # reset reverse video
        LESS_TERMCAP_us="\E[1;32m";     # begin underline
        LESS_TERMCAP_ue="\E[0m";        # reset underline
      };
    };

    git.enable = true;
    htop.enable = true;
    bat.enable = true;
    bandwhich.enable = true;

    command-not-found.enable = false;
    #nix-index.enable = true;

    nano.enable = false;
    neovim = {
      enable = true;
      defaultEditor = true;
      viAlias = true;
      vimAlias = true;
    };
  };

  services.openssh.enable = lib.mkDefault false;
  # services.openssh = {
  #   enable = true;
  #   settings = {
  #     PasswordAuthentication = false;
  #     PermitRootLogin = "no";
  #   };
  # };
}