anchor.diff:  , speech-dispatcher
   , speex
   , speexdsp
  -, xproto
  +, xorgproto
   
   , mumbleOverlay ? true
   , releaseType ? "release"
  
positive.code:     speech-dispatcher
      speex
      speexdsp
      xproto
    ] ++ optionals (config == "murmur") [
      grpc
      ice
  
negative.code: , alsa-lib
  , avahi
  , boost
  , grpc
  , ice
  , libbsd
  , libcap
  , libsndfile
  