anchor.diff: -{ stdenv, fetchFromGitHub, fetchpatch
  -, talloc, docutils }:
  +{ stdenv, fetchFromGitHub
  +, talloc, docutils, swig, python, coreutils, enablePython ? true }:
   
  -({ version, rev, sha256, patches }: stdenv.mkDerivation {
  -  name = "proot-${version}";
  -  inherit version;
  +stdenv.mkDerivation rec {
  +  pname = "proot";
  +  version = "5.1.0.20190305";
   
     src = fetchFromGitHub {
  -    inherit rev sha256;
       repo = "proot";
       owner = "proot-me";
  +    rev = "ff61c86cb26f71c06af22574d9d4cc3a77292781";
  +    sha256 = "0qink34bjv0lshf3c8997w39r8yxgbhxpjbxw47l5xkvimlpc0dl";
     };
   
  -  buildInputs = [ talloc ];
  -  nativeBuildInputs = [ docutils ];
  +  postPatch = ''
  +    substituteInPlace src/GNUmakefile \
  +      --replace /bin/echo ${coreutils}/bin/echo
  +  '';
  +
  +  buildInputs = [ talloc ] ++ stdenv.lib.optional enablePython python;
  +  nativeBuildInputs = [ docutils ] ++ stdenv.lib.optional enablePython swig;
   
     enableParallelBuilding = true;
  -
  -  inherit patches;
   
     makeFlags = [ "-C src" ];
   
  
positive.code:     description = "User-space implementation of chroot, mount --bind and binfmt_misc";
      platforms = platforms.linux;
      license = licenses.gpl2;
      maintainers = with maintainers; [ ianwookim makefu veprbl ];
    };
  })
  (if stdenv.isAarch64 then rec {
    version = "5.1.0";
    sha256 = "0azsqis99gxldmbcg43girch85ysg4hwzf0h1b44bmapnsm89fbz";
    rev = "v${version}";
    patches = [
      (fetchpatch { # debian patch for aarch64 build
        sha256 = "18milpzjkbfy5ab789ia3m4pyjyr9mfzbw6kbjhkj4vx9jc39svv";
        url = "https://sources.debian.net/data/main/p/proot/5.1.0-1.2/debian/patches/arm64.patch";
      })
    ];
  } else {
    version = "5.1.0.20190305";
    sha256 = "0qink34bjv0lshf3c8997w39r8yxgbhxpjbxw47l5xkvimlpc0dl";
    rev = "ff61c86cb26f71c06af22574d9d4cc3a77292781";
    patches = [];
  })
  
negative.code:     make -C doc proot/man.1
    '';
  
    installFlags = [ "PREFIX=${placeholder "out"}" ];
  
    postInstall = ''
      install -Dm644 doc/proot/man.1 $out/share/man/man1/proot.1
  