diff --git a/Makefile b/Makefile
index f002375..4e8536f 100644
--- a/Makefile
+++ b/Makefile
@@ -8,7 +8,7 @@ DATADIR=/etc/sgs-xl/data
 # choose this if you want debugging help
 CPPFLAGS=-g -ggdb -W -Wall -std=c++17 -DCFG_DIR=\"$(CFGDIR)\" -DDATA_DIR=\"$(DATADIR)\"
 # or, you can choose this for a much smaller executable without debugging help
-#CPPFLAGS= -W -Wall -std=c++17 -DCFG_DIR=\"$(CFGDIR)\" -DDATA_DIR=\"$(DATADIR)\"
+#CPPFLAGS= -W -Wall -O3 -std=c++17 -DCFG_DIR=\"$(CFGDIR)\" -DDATA_DIR=\"$(DATADIR)\"
 
 SRCS = $(wildcard *.cpp)
 OBJS = $(SRCS:.cpp=.o)