diff --git a/scripts/targets.emscripten.mak b/scripts/targets.emscripten.mak
index 7c9900fe0..436890c53 100644
--- a/scripts/targets.emscripten.mak
+++ b/scripts/targets.emscripten.mak
@@ -1,12 +1,12 @@
 $(BUILD_DIR)/epsilon.packed.js: LDFLAGS += --memory-init-file 0
-$(BUILD_DIR)epsilon.packed.js: $(objs) $(app_objs) $(app_image_objs)
+$(BUILD_DIR)/epsilon.packed.js: $(objs) $(call object_for,$(epsilon_src))
 
-$(BUILD_DIR)/simulator.zip: epsilon.packed.js
+$(BUILD_DIR)/simulator.zip: $(BUILD_DIR)/epsilon.packed.js
 	@rm -rf $(basename $@)
-	@mkdir $(basename $@)
-	@cp epsilon.packed.js $(basename $@)/epsilon.js
+	@mkdir -p $(basename $@)
+	@cp $^ $(basename $@)/epsilon.js
 	@cp ion/src/emscripten/background.jpg $(basename $@)/
 	@cp ion/src/emscripten/simulator.html $(basename $@)/
 	@echo "ZIP     $@"
-	@zip -r -9 $@ $(basename $@) > /dev/null
+	@zip -r -9 -j $@ $(basename $@) > /dev/null
 	@rm -rf $(basename $@)