anchor.diff:        }).config;
   
         tarball = config.system.build.tarball;
  +
       in
         tarball //
           { meta = {
  
positive.code:   pkgs = import <nixpkgs> { system = "x86_64-linux"; };
  
  
    makeIso =
      { module, type, description ? type, maintainers ? ["eelco"], system }:
  
  
negative.code:     with import <nixpkgs> { inherit system; };
  
      let
  
        config = (import lib/eval-config.nix {
          inherit system;
  