diff --git a/backends/events/sdl/sdl-events.cpp b/backends/events/sdl/sdl-events.cpp
index 65d5b62beb3..ce846a0836d 100644
--- a/backends/events/sdl/sdl-events.cpp
+++ b/backends/events/sdl/sdl-events.cpp
@@ -29,6 +29,7 @@
 
 #include "backends/events/sdl/sdl-events.h"
 #include "backends/platform/sdl/sdl.h"
+#include "backends/graphics/graphics.h"
 #include "common/config-manager.h"
 
 // FIXME move joystick defines out and replace with confile file options
diff --git a/backends/modular-backend.cpp b/backends/modular-backend.cpp
index 52edcebd247..19cba89af3e 100644
--- a/backends/modular-backend.cpp
+++ b/backends/modular-backend.cpp
@@ -24,7 +24,13 @@
  */
 
 #include "backends/modular-backend.h"
+
 #include "backends/fs/fs-factory.h"
+#include "backends/events/default/default-events.h"
+#include "backends/audiocd/default/default-audiocd.h"
+#include "backends/mutex/null/null-mutex.h"
+#include "backends/graphics/null/null-graphics.h"
+
 #include "gui/message.h"
 
 ModularBackend::ModularBackend()
diff --git a/backends/modular-backend.h b/backends/modular-backend.h
index 0f9b604de45..863d9c2a81f 100644
--- a/backends/modular-backend.h
+++ b/backends/modular-backend.h
@@ -29,10 +29,9 @@
 #include "common/system.h"
 #include "common/timer.h"
 #include "common/savefile.h"
-#include "backends/events/default/default-events.h"
-#include "backends/audiocd/default/default-audiocd.h"
-#include "backends/mutex/null/null-mutex.h"
-#include "backends/graphics/null/null-graphics.h"
+
+class GraphicsManager;
+class MutexManager;
 
 /**
  * Base class for modular backends.