anchor.diff:  { nixpkgs ? { outPath = (import ./all-packages.nix {}).lib.cleanSource ../..; revCount = 1234; shortRev = "abcdef"; }
   , officialRelease ? false
   , # The platforms for which we build Nixpkgs.
  -  supportedSystems ? [ "x86_64-linux" "i686-linux" "x86_64-darwin" ]
  +  supportedSystems ? [ "x86_64-linux" "i686-linux" ]
   , scrubJobs ? true
   }:
   
  
positive.code: 
        stdenvBootstrapTools.x86_64-linux =
          { inherit (import ../stdenv/linux/make-bootstrap-tools.nix { system = "x86_64-linux"; }) dist test; };
  
        stdenvBootstrapTools.x86_64-darwin =
          let
            bootstrap = import ../stdenv/darwin/make-bootstrap-tools.nix { system = "x86_64-darwin"; };
          in {
            # Lightweight distribution and test
            inherit (bootstrap) dist test;
            # Test a full stdenv bootstrap from the bootstrap tools definition
            inherit (bootstrap.test-pkgs) stdenv;
          };
  
      } // (mapTestOn ((packagePlatforms pkgs) // rec {
  
  
negative.code:         xf86videovesa = linux;
          xf86videovmware = linux;
          xf86videomodesetting = linux;
          xfs = linux;
          xinput = linux;
          xkbcomp = linux;
          xlsclients = linux;
          xmessage = linux;
          xorgserver = linux;
          xprop = linux;
          xrandr = linux;
          xrdb = linux;
          xset = linux;
          xsetroot = linux;
          xwininfo = linux;
        };
  
        xfce = {
  