anchor.diff:  { stdenv
   , fetchurl
  +, pkg-config
   , alsaLib
   , audiofile
   , libjack2
  
positive.code: , libsndfile
  , lilv
  , lv2
  }:
  
  # TODO: fix readline, ncurses, lilv, liblo, liboil and python. See configure log.
  
  stdenv.mkDerivation rec {
    pname = "ecasound";
  
negative.code:     sha256 = "1m7njfjdb7sqf0lhgc4swihgdr4snkg8v02wcly08wb5ar2fr2s6";
    };
  
    nativeBuildInputs = [
      pkg-config
    ];
  
    buildInputs = [
      alsaLib
      audiofile
      libjack2
      liblo
      liboil
      libsamplerate
      libsndfile
      lilv
      lv2
      ncurses
      readline
    ];
  
    strictDeps = true;
  
    configureFlags = "--enable-liblilv --with-extra-cppflags=-Dnullptr=0";
  
    postPatch = ''
      sed -i -e '
        s@^#include <readline.h>@#include <readline/readline.h>@
        s@^#include <history.h>@#include <readline/history.h>@
        ' ecasound/eca-curses.cpp
    '';
  
    meta = {
      description = "Software package designed for multitrack audio processing";
  