diff --git a/conmon/Makefile b/conmon/Makefile
index 034ba59a..4be94283 100644
--- a/conmon/Makefile
+++ b/conmon/Makefile
@@ -2,7 +2,7 @@ src = $(wildcard *.c)
 obj = $(src:.c=.o)
 
 override LIBS += $(shell pkg-config --libs glib-2.0 json-glib-1.0)
-override CFLAGS += -std=c99 -Wall -Wextra $(shell pkg-config --cflags glib-2.0)
+override CFLAGS += -std=c99 -Os -Wall -Wextra $(shell pkg-config --cflags glib-2.0)
 
 conmon: $(obj)
 	$(CC) -o $@ $^ $(CFLAGS) $(LIBS)