{
  config,
  pkgs,
  lib,
  inputs,
  ...
}: {
  # Bootloader.
  boot.loader = {
    efi.canTouchEfiVariables = true;
    systemd-boot = {
      enable = true;
      configurationLimit = 5;
    };
  };

  # Garbage collection
  nix = {
    gc = {
      automatic = true;
      dates = "weekly";
      options = "--delete-older-than 1w";
    };
    nixPath = ["nixpkgs=${inputs.nixpkgs}"];
    settings = {
      auto-optimise-store = true;
      download-buffer-size = 524288000;
      experimental-features = ["nix-command" "flakes"];
    };
  };

  # Allow unfree packages
  nixpkgs.config.allowUnfree = true;

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

  # Select internationalisation properties.
  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_GB.UTF-8";
  };

  # Configure keymap
  console.keyMap = lib.mkDefault "jp106";

  services.xserver.xkb = {
    layout = lib.mkDefault "jp";
    model = lib.mkDefault "jp106";
  };

  # Allow power management
  powerManagement.enable = true;

  # Enable networking
  networking.networkmanager.enable = true;

  # Catppuccin
  catppuccin = {
    enable = true;
    flavor = "mocha";
  };

  # Android debug tools
  programs.adb.enable = true;

  # Bash config
  programs.bash = {
    blesh.enable = true;
  };

  # zsh config
  programs.zsh = {
    enable = true;
    enableCompletion = true;
    enableBashCompletion = true;
    autosuggestions.enable = true;
    syntaxHighlighting.enable = true;
  };

  # Define a user account
  users.users.chase = {
    isNormalUser = true;
    description = "Chase";
    extraGroups = [
      "adbusers"
      "audio"
      "cdrom"
      "dialout"
      "kvm"
      "networkmanager"
      "tss"
      "video"
      "wheel"
    ];
    openssh.authorizedKeys.keys = [
      "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIFSQX+s8Krl312DcnUtoEWOA2silcUnt5URtyVZz8Yek"
    ];
    shell = pkgs.zsh;
  };

  # Install git and enable cache
  programs.git = {
    enable = true;
    config = {
      init = {
        defaultBranch = "main";
      };
      credential = {
        helper = "cache --timeout 21600";
      };
    };
  };

  # Install Neovim
  programs.neovim = {
    enable = true;
    defaultEditor = true;
    configure = {
      customRC = ''
        set autoindent
        set number relativenumber
        set tabstop=4
        colorscheme catppuccin-mocha
      '';
      packages.myVimPackage = with pkgs.vimPlugins; {
        start = [catppuccin-nvim];
      };
    };
    viAlias = true;
    vimAlias = true;
  };

  # ssh agent
  programs.gnupg.agent.enable = true;

  programs.ssh = {
    enableAskPassword = false;
  };

  sops = {
    defaultSopsFile = ../secrets.yaml;
    validateSopsFiles = false;
    age = {
      sshKeyPaths = ["/etc/ssh/ssh_host_ed25519_key"];
      keyFile = "/var/lib/sops-nix/key.txt";
      generateKey = true;
    };
    secrets = {
      "smb-username" = {};
      "smb-password" = {};
    };
    templates = {
      "smb-credentials".content = ''
        username=${config.sops.placeholder.smb-username}
        password=${config.sops.placeholder.smb-password}
      '';
    };
  };

  # List packages installed in system profile.
  environment.systemPackages = with pkgs; [
    alejandra
    bitwarden-cli
    cifs-utils
    flashrom
    gcc
    nixd
    pam_u2f
    pciutils
    python3
    qemu
    rustup
    sbctl
    sops
    usbutils
    wget
    yubikey-manager
  ];

  security.pam = lib.optionalAttrs pkgs.stdenv.isLinux {
    sshAgentAuth.enable = true;
    u2f = {
      enable = true;
      settings = {
        cue = false;
        authFile = "~/.config/Yubico/u2f_keys";
      };
    };
    services = {
      login.u2fAuth = true;
      sudo = {
        u2fAuth = true;
      };
    };
  };

  security.tpm2 = {
    enable = true;
    pkcs11.enable = true;
    tctiEnvironment.enable = true;
  };

  services.fstrim.enable = lib.mkDefault true;

  # Firmware updates
  services.fwupd.enable = true;

  # Enable the OpenSSH daemon.
  services.openssh = {
    enable = true;
    settings = {
      PermitRootLogin = "no";
      PasswordAuthentication = false;
      KbdInteractiveAuthentication = false;
    };
  };

  services.pcscd.enable = true;

  # Enable CUPS to print documents.
  services.printing.enable = true;

  services.udev = {
    packages = with pkgs; [
      yubikey-personalization
    ];
    extraRules = ''
      SUBSYSTEM=="usb", ATTRS{idVendor}=="04b8", ATTRS{idProduct}=="0202", MODE="0666", GROUP="dialout"
    '';
  };

  services.yubikey-agent.enable = true;
}
