diff --git a/Makefile.am b/Makefile.am
index cce4d0f..2a4bc76 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -264,18 +264,19 @@ sgpemv2_LDADD = \
 # Please keep this in sorted order:
 sgpemv2_SOURCES = \
 	src/graphical_terminal_io.cc \
+	src/gui_builder.cc \
 	src/main.cc \
 	src/main_window.cc \
 	src/observer.cc \
 	src/parse_opts.cc \
 	src/simulation.cc \
 	src/standard_io.cc \
-	src/start_gui.cc \
 	src/text_simulation.cc
 
 noinst_HEADERS += \
 	src/graphical_simulation.hh \
 	src/graphical_terminal_io.hh \
+	src/gui_builder.hh \
 	src/io_manager.hh \
 	src/main.hh \
 	src/main_window.hh \
@@ -283,7 +284,6 @@ noinst_HEADERS += \
 	src/parse_opts.hh \
 	src/simulation.hh \
 	src/standard_io.hh \
-	src/start_gui.hh \
 	src/text_simulation.hh
 
 #  ---------- glade files -----------
diff --git a/src/gui_builder.cc b/src/gui_builder.cc
index 25b8766..57e0704 100644
--- a/src/gui_builder.cc
+++ b/src/gui_builder.cc
@@ -28,7 +28,6 @@
 #include <gtkmm/main.h>
 #include <gtkmm/menuitem.h>
 
-#include <cassert>
 #include <iostream>
 
 using namespace sgpem;
@@ -47,19 +46,14 @@ GuiBuilder::GuiBuilder(const std::string& gladefile)
 	// Glade::Xml::get_widget_derived -- better --)
 	MenuItem* file_quit = NULL;
 	_refXml->get_widget("MenuItem.File.Quit", file_quit);
-	assert(file_quit != NULL);
  	file_quit->signal_activate().connect(sigc::ptr_fun(&Main::quit));
 
 	// About dialog
 	MenuItem* help_about = NULL;
 	_refXml->get_widget("MenuItem.Help.About", help_about);
-	assert(help_about != NULL);
 	AboutDialog* about_dialog = NULL;
 	_refXml->get_widget("AboutDialog", about_dialog);
-	assert(about_dialog != NULL);
 	help_about->signal_activate().connect(sigc::mem_fun(*about_dialog, &Window::show));
-
-	//	main_window.show_all_children();
 }
 
 
@@ -73,7 +67,6 @@ GuiBuilder::get_initial_window() const
 {
 	Gtk::Window* main_window = NULL;
 	_refXml->get_widget("MainWindow", main_window);
-	assert(main_window != NULL);
 	return *main_window;
 }