anchor.diff:    passthru = {
       srcVerification = fetchurl {
         failEarly = true;
  -      pgpsigUrls = map (n: "${n}.sign") baseTarballs;
  -      pgpDecompress = true;
  -      pgpKeyFingerprint = "E1B7 1E33 9E20 A10A 676F  7CB6 9AFB 1D68 1A12 5177";
  -      inherit (src) urls outputHash outputHashAlgo;
  +      inherit (src)
  +        urls
  +        outputHash
  +        outputHashAlgo;
  +      fullOpts = {
  +        pgpsigUrls = map (n: "${n}.sign") baseTarballs;
  +        pgpDecompress = true;
  +        pgpKeyFingerprint = "E1B7 1E33 9E20 A10A 676F  7CB6 9AFB 1D68 1A12 5177";
  +      };
       };
     };
   
  
positive.code:   src = fetchurl {
      urls = map (n: "${n}.xz") baseTarballs;
      hashOutput = false;
      sha256 = "245ec2f9abb51bcc233b64f6f3e9ac8e5cd16ffd35dba9450f83ce2803844cda";
    };
  
    buildInputs = [
  
negative.code: }:
  
  let
    version = "2.3.3";
    name = "nfs-utils-${version}";
  
    baseTarballs = [
  