anchor.diff:  
       shell = stdenvLinuxBoot4Pkgs.bash + "/bin/bash";
   
  -    fetchurlBoot = fetchurl;
  +    fetchurlBoot = stdenvLinuxBoot0.fetchurlBoot;
   
       extraAttrs = {
         inherit (stdenvLinuxBoot3Pkgs) glibc;
  
positive.code:     overrides = pkgs: {
        inherit (stdenvLinuxBoot1Pkgs) perl;
      };
      inherit fetchurl;
    };
  
  
  
negative.code:       binutils = bootstrapTools;
        coreutils = bootstrapTools;
      };
    };
  
  
  