anchor.diff:    # You should generally set this to the total number of logical cores in your system.
     # $ sysctl -n hw.ncpu
     nix.maxJobs = 1;
  +  nix.buildCores = 1;
   }
  
positive.code: { config, lib, pkgs, ... }:
  {
  
    # List packages installed in system profile. To search by name, run:
    # $ nix-env -qaP | grep wget
    environment.systemPackages =
  
negative.code:   # Create /etc/bashrc that loads the nix-darwin environment.
    programs.bash.enable = true;
  
    # Used for backwards compatibility, please read the changelog before changing.
    # $ darwin-rebuild changelog
    system.stateVersion = 2;
  