anchor.diff:  
     buildInputs = [
       alsaLib
  +    bc  # for the Everything module calculator mode
       bzip2
       efl
       gdbm
  
positive.code: { stdenv, fetchurl, meson, ninja, pkgconfig, gettext, alsaLib, bzip2,
    efl, gdbm, libXdmcp, libXrandr, libcap, libffi, libpthreadstubs,
    libxcb, luajit, mesa, pam, pcre, xcbutilkeysyms, xkeyboard_config,
  
    bluetoothSupport ? true, bluez5,
    pulseSupport ? !stdenv.isDarwin, libpulseaudio,
  
negative.code: 
      substituteInPlace src/bin/e_import_config_dialog.c \
        --replace "e_prefix_bin_get()" "\"${efl}/bin\""
  
      substituteInPlace src/modules/everything/evry_plug_calc.c \
        --replace "ecore_exe_pipe_run(\"bc -l\"" "ecore_exe_pipe_run(\"${bc}/bin/bc -l\""
    '';
  
    mesonFlags = [ "-Dsystemdunitdir=lib/systemd/user" ];
  