anchor.diff:      owner = "axboe";
       repo = "fio";
       rev = "fio-${version}";
  -    sha256 = "0g26xvbb60f96ks8q7jpap0xc2grb5j5w4m4glz910ndgf0s45wm";
  +    inherit sha256;
     };
   
     buildInputs = [ libaio python zlib ];
  
positive.code:     homepage = "http://git.kernel.dk/?p=fio.git;a=summary";
      description = "Flexible IO Tester - an IO benchmark tool";
      license = licenses.gpl2;
      platforms = platforms.linux;
    };
  }
  
negative.code: { stdenv, fetchFromGitHub, libaio, python, zlib }:
  
  let
    version = "2.9";
    sha256 = "10x5b1f1pdsh33kqzc8yf2v4mijlmkh72lmh9za6kz7hb3hp1nvi";
  in
  
  stdenv.mkDerivation rec {
    name = "fio-${version}";
  