{...}:
{
  boot.cleanTmpDir = true;
  networking.firewall.allowPing = true;
  nix.binaryCaches = [ "https://cache.nixos.org" ];
  nix.gc.automatic = true;
  nix.gc.dates = "Sunday 02:15";
  nix.optimise.automatic = true;
  nix.optimise.dates = [ "Sunday 02:30" ];
  #nixpkgs.overlays = overlays;
  programs.mosh.enable = true;
  programs.mosh.withUtempter = true;
  security.acme.email = "ben@bsima.me";
  security.acme.acceptTerms = true;
  security.sudo.wheelNeedsPassword = false;
  services.clamav.daemon.enable = true; # security
  services.clamav.updater.enable = true; # security
  services.fail2ban.enable = true; # security
  services.openssh.enable = true;
  services.openssh.openFirewall = true;
  services.openssh.forwardX11 = true;
  services.openssh.passwordAuthentication = false;
  services.openssh.permitRootLogin = "prohibit-password";
  system.autoUpgrade.enable = false; # 'true' breaks our nixpkgs pin
}