anchor.diff: -{avahi, dbus, fetchurl, git, gzip, libav, libiconv, openssl, pkgconfig, python
  +{avahi, dbus, fetchurl, git, gnutar, gzip, libav, libiconv, openssl, pkgconfig, python
   , stdenv, which, zlib}:
   
   with stdenv.lib;
   
  -let version = "4.0.6";
  +let version = "4.0.7";
       pkgName = "tvheadend";
   
   in
  
positive.code: 
    src = fetchurl {
      url = "https://github.com/tvheadend/tvheadend/archive/v${version}.tar.gz";
      sha256 = "05jidg7jma3mban40iy1bg3sirw6crscxkd8b70if4kjlf86i31l";
    };
  
    enableParallelBuilding = true;
  
negative.code:   # cannot happen during build.
    configureFlags = [ "--disable-dvbscan" ];
  
    buildInputs = [ avahi dbus git gnutar gzip libav libiconv openssl pkgconfig python
      which zlib ];
  
    preConfigure = ''
      patchShebangs ./configure
      substituteInPlace src/config.c --replace /usr/bin/tar ${gnutar}/bin/tar
    '';
  
    meta = {
      description = "TV steaming server";
  