diff --git a/apps/Makefile b/apps/Makefile
index d3cb9321f..34eeb7463 100644
--- a/apps/Makefile
+++ b/apps/Makefile
@@ -89,7 +89,10 @@ epsilon_src += $(addprefix apps/, \
   i18n.py \
 )
 
-$(call object_for,$(app_src) $(epsilon_src)): $(BUILD_DIR)/apps/i18n.h
+all_app_src = $(app_src) $(epsilon_src)
+
+$(call object_for,$(all_app_src)): $(BUILD_DIR)/apps/i18n.h
+$(call object_for,$(all_app_src)): $(BUILD_DIR)/python/port/genhdr/qstrdefs.generated.h
 
 $(BUILD_DIR)/epsilon.$(EXE): $(call object_for,$(epsilon_src))