anchor.diff: -{ stdenv, pkgconfig, fetchurl, python3Packages
  -, intltool, itstool, libtool, texinfo, autoreconfHook
  -, glib, dotconf, libsndfile
  +{ stdenv
  +, pkgconfig
  +, fetchurl
  +, python3Packages
  +, intltool
  +, itstool
  +, libtool
  +, texinfo
  +, autoreconfHook
  +, glib
  +, dotconf
  +, libsndfile
   , withLibao ? true, libao
   , withPulse ? false, libpulseaudio
   , withAlsa ? false, alsaLib
  
positive.code: 
    meta = with stdenv.lib; {
      description = "Common interface to speech synthesis";
      homepage = https://devel.freebsoft.org/speechd;
      license = licenses.gpl2Plus;
      maintainers = with maintainers; [ berce ];
      platforms = platforms.linux;
  
negative.code:     sha256 = "1wvck00w9ixildaq6hlhnf6wa576y02ac96lp6932h3k1n08jaiw";
    };
  
    nativeBuildInputs = [
      pkgconfig
      autoreconfHook
      intltool
      libtool
      itstool
      texinfo
      wrapPython
    ];
  
    buildInputs = [
      glib
      dotconf
      libsndfile
      libao
      libpulseaudio
      alsaLib
      python
    ] ++ optionals withEspeak [
      espeak
      sonic
      pcaudiolib
    ] ++ optional withFlite flite
      ++ optional withPico svox
      # TODO: add flint/festival support with festival-freebsoft-utils package
      # ++ optional withFestival festival-freebsoft-utils
  