anchor.diff:  , mpg123
   , twolame
   , gtkSupport ? false, gtk3 ? null
  +, qt5Support ? false, qt5 ? null
   , raspiCameraSupport ? false, libraspberrypi ? null
   , enableJack ? true, libjack2
   , libXdamage
  
positive.code:   mesonFlags = [
      "-Dexamples=disabled" # requires many dependencies and probably not useful for our users
      "-Ddoc=disabled" # `hotdoc` not packaged in nixpkgs as of writing
      "-Dqt5=disabled" # not clear as of writing how to correctly pass in the required qt5 deps
    ] ++ optionals (!gtkSupport) [
      "-Dgtk3=disabled"
    ] ++ optionals (!enableJack) [
  
negative.code:   ] ++ optionals gtkSupport [
      # for gtksink
      gtk3
    ] ++ optionals qt5Support (with qt5; [
      qtbase
      qtdeclarative
      qtwayland
      qtx11extras
    ]) ++ optionals stdenv.isDarwin [
      darwin.apple_sdk.frameworks.Cocoa
    ] ++ optionals stdenv.isLinux [
      libv4l
  