anchor.diff:  # note: the resulting program has to be invoced as
   # 'dropbox' because the internal python engine takes
   # uses the name of the program as starting point.
  -#
  -# todo: dropbox is shipped with some copies of libraries.
  -# replace these libraries with the appropriate ones in
  -# nixpkgs.
  +
  +# Dropbox ships with its own copies of some libraries.
  +# Unfortunately, upstream makes changes to the source of
  +# some libraries, rendering them incompatible with the
  +# open-source versions. Wherever possible, we must try
  +# to make the bundled libraries work, rather than replacing
  +# them with our own.
   
   let
     arch = if stdenv.system == "x86_64-linux" then "x86_64"
  
positive.code: { stdenv, fetchurl, makeDesktopItem, makeWrapper
  , dbus_libs, gcc, glib, libdrm, libffi, libICE, librsync, libSM
  , libX11, libXmu, ncurses, popt, qt5, zlib
  }:
  
  
negative.code: 
    ldpath = stdenv.lib.makeSearchPath "lib"
      [
        dbus_libs gcc glib libdrm libffi libICE libSM libX11
        libXmu ncurses popt qt5.base qt5.declarative qt5.webkit
        zlib
      ];
  