diff --git a/Makefile b/Makefile
index 1c86195..0238aab 100644
--- a/Makefile
+++ b/Makefile
@@ -5,7 +5,7 @@ export CPPFLAGS += -I"$(shell cd)"
 else
 export CPPFLAGS += -I"$(shell pwd)"
 endif
-export CXXFLAGS := -Wall -O1
+export CXXFLAGS := -Wall -O2
 
 LDFLAGS := -lfl