diff --git a/apps/Makefile b/apps/Makefile
index d567a2d6..f4dc303e 100644
--- a/apps/Makefile
+++ b/apps/Makefile
@@ -3,7 +3,7 @@ COREPATH ?= ../core
 
 include $(COREPATH)/../Makefile.defs
 
-exclude_modules = mp3 examples py_sems
+exclude_modules ?= mp3 examples py_sems
 modules ?= $(filter-out $(exclude_modules) \
 		$(wildcard Makefile*) CVS, \
 		$(wildcard *) ) examples/tutorial/cc_acc