diff --git a/Makefile b/Makefile
index 8e328b1..a22b009 100644
--- a/Makefile
+++ b/Makefile
@@ -23,7 +23,7 @@ all: release
 
 jars/classes.jar: $(SRCS)
 	@mkdir -p jars
-	$(KOTLINC) $(KOTLINFLAGS) $< 
+	$(KOTLINC) $(KOTLINFLAGS) $?
 
 clean: 
 	rm -rf jars/