anchor.diff:    src = fetchurl {
       url = "https://raw.githubusercontent.com/wiki/SELinuxProject/selinux/"
         + "files/releases/${release}/${name}.tar.gz";
  -    sha256 = "94c9e97706280bedcc288f784f67f2b9d3d6136c192b2c9f812115edba58514f";
  +    hashOutput = false;
  +    sha256 = "4ea2dde50665c202253ba5caac7738370ea0337c47b251ba981c60d24e1a118a";
     };
   
     nativeBuildInputs = [
  
positive.code: }:
  
  let
    release = "20160223";
    version = "2.5";
  in
  stdenv.mkDerivation rec {
    name = "libselinux-${version}";
  
negative.code:     description = "SELinux userland library";
      homepage = http://userspace.selinuxproject.org;
      license = licenses.gpl2;
      maintainers = with maintainers; [
        wkennington
      ];
      platforms = with platforms;
        x86_64-linux;
    };
  }
  