diff --git a/Makefile b/Makefile
index 9afbb54..9d16a38 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-override CFLAGS := -g -O2 -Wall -Wextra -D_FORTIFY_SOURCE=2 -fstack-protector --param ssp-buffer-size=4 $(CFLAGS)
+CFLAGS ?= -g -O2 -Wall -Wextra -D_FORTIFY_SOURCE=2 -fstack-protector --param ssp-buffer-size=4
 # for install-home
 BINDIR ?= $(HOME)/bin