nix/groups/servers/default.nix

{...}: {
  nix.settings = {
    trusted-users = ["root" "@wheel"];
  };

  security = {
    sudo = {
      enable = true;
      wheelNeedsPassword = true;
    };

    pam = {
      sshAgentAuth.enable = true;
      services.sudo.sshAgentAuth = true; # pam_ssh_agent_auth module
    };
  };
}