anchor.diff:    passthru = {
       srcVerified = fetchurl rec {
         failEarly = true;
  -      urls = tarballUrls "4.2";
  +      urls = tarballUrls "4.2.1";
         pgpsigUrls = map (n: "${n}.sig") urls;
         pgpKeyFingerprint = "3D25 54F0 A153 38AB 9AF1  BB9D 96B0 4715 6338 B6D4";
         inherit (src) outputHashAlgo;
  -      outputHash = "4e5ce3b62fe5d75ff8db92b7f6df91e476d10c3aceebf1639796dc5bfece655f";
  +      outputHash = "d6e262bf3601b42d2b1e4ef8310029e1dcf20083c5446b4b7aa67081fdffc589";
       };
     };
   
  
positive.code: }:
  
  let
    version = "4.2";
  
    tarballUrls = version: [
      "mirror://gnu/make/make-${version}.tar.bz2"
  
negative.code:   src = fetchurl {
      urls = tarballUrls version;
      allowHashOutput = false;
      sha256 = "d6e262bf3601b42d2b1e4ef8310029e1dcf20083c5446b4b7aa67081fdffc589";
    };
  
    patches = [
  