Hi,
the documentation does not mentions the libboost-dev dependency. However, liquidpcb/trunk/src/liquid_message.h includes boost/function.hpp and boost/bind.hpp. Either liquidpcb/trunk/external_libs/boost_signals is not built correctly, or more functionality is required? However, since boost is a pretty heavy-weight dependency and only boost::shared_ptr seem to be used, wouldn't it be better to implement shared pointers locally?
--- These files reference boost symbols:
liquidpcb/trunk/src/widgets/widget_sizer.h
liquidpcb/trunk/src/widgets/widget_hex_menu.h
liquidpcb/trunk/src/widgets/world_widget.h
liquidpcb/trunk/src/widgets/widget_windows.h
liquidpcb/trunk/src/widgets/widget_typesizer.h
liquidpcb/trunk/src/liquid_message.h
liquidpcb/trunk/src/pcb_window.h