anchor.diff:    src = fetchurl {
       urls = map (n: "${n}.xz") tarballUrls;
       hashOutput = false;
  -    sha256 = "805bdb0031c21a0a5d2ba295a8c9bdd8ba831a68c3fa801aab85677ec902d783";
  +    sha256 = "09095cbc3bc2b6aa9d09c93146fb4d7437c51d2572f6918b74fe990fcdcb91af";
     };
   
     nativeBuildInputs = [
  
positive.code: , lzo
  , util-linux_lib
  , zlib
  }:
  
  let
    version = "4.13.3";
  
    tarballUrls = [
      "mirror://kernel/linux/kernel/people/kdave/btrfs-progs/btrfs-progs-v${version}.tar"
  
negative.code:     lzo
      util-linux_lib
      zlib
      zstd
    ];
  
    passthru = {
  