anchor.diff:  # optional server deps
   , libmicrohttpd
   , libsodium
  +, withSystemd ? stdenv.isLinux
  +, systemd ? null
   
   # options
   , buildClient ? true
  
positive.code: { lib
  , mkDerivation
  , fetchurl
  , cmake
  , extra-cmake-modules
  
  # common deps
  
negative.code: 
  # client deps
  , qtbase
  , qtkeychain
  , qtmultimedia
  , qtsvg
  , qttools
  