diff --git a/quad/library.mk b/quad/library.mk
index 1a4aa5dd4490cbc4196eaaf22de2fc6efb633e6f..88914b2dad79799038b95bb1db9924dde324413b 100644
--- a/quad/library.mk
+++ b/quad/library.mk
@@ -14,6 +14,8 @@ TESTOBJECTS = $(patsubst $.c, %.o, $(TESTSOURCES))
 
 TARGET = $(LIBDIR)/lib$(NAME).a
 TESTBIN = run_tests
+
+# For Unity; allows custom configuration
 UNITYDEFINES = -DUNITY_INCLUDE_CONFIG_H
 
 .PHONY: default test clean