+Qt and QJSON will be required if `-DENABLE_GUI=TRUE` is passed to CMake, and
+never used if `-DENABLE_GUI=FALSE` is passed instead. The implicit default is
+`-DENABLE_GUI=AUTO`, which will build the GUI if Qt is available, using the
+bundled QJSON if it is not found on the system.
+
+
+The code also depends on zlib, libpng, and snappy libraries, but the bundled
+sources are always used regardless of system availability, to make the wrapper
+shared-objects/DLL self contained, and to prevent symbol collisions when
+tracing.