anchor.diff:        ninja
         nixops
         mercurial
  +      packer
         ripgrep
         terraform
         urweb
  +      vagrant
         xz
       ];
   
  
positive.code: 
    services.activate-system.enable = true;
    services.nix-daemon.enable = true;
  
    system.stateVersion = 4;
  
    nix.maxJobs = 2;
    nix.package = pkgs.nix;
    nix.trustedUsers = [ "root" "cbarrett" ];
  }
  
negative.code: { config, lib, options, pkgs, ... }:
  {
    environment.systemPackages =
      with pkgs;
  