anchor.diff:    meta = with lib; {
       description = "Open-source braille translator and back-translator";
       homepage = "http://liblouis.org/";
  -    license = licenses.lgpl21;
  +    license = with licenses; [
  +      lgpl21Plus # library
  +      gpl3Plus # tools
  +    ];
       maintainers = with maintainers; [ jtojnar ];
       platforms = platforms.unix;
     };
  
positive.code: { fetchFromGitHub
  , lib
  , stdenv
  , fetchpatch
  , autoreconfHook
  , pkg-config
  , gettext
  
negative.code: 
  stdenv.mkDerivation rec {
    pname = "liblouis";
    version = "3.22.0";
  
    outputs = [ "out" "dev" "man" "info" "doc" ];
  
    src = fetchFromGitHub {
      owner = "liblouis";
      repo = "liblouis";
      rev = "v${version}";
      sha256 = "sha256-EI/uaHXe0NlqdEw764q0SjerThYEVLRogUlmrsZwXnY=";
    };
  
    nativeBuildInputs = [
      autoreconfHook
  