-CFLAGS = -Os ${INCS} -DVERSION=\"${VERSION}\"
-LDFLAGS = ${LIBS}
-#CFLAGS = -g -Wall -O2 ${INCS} -DVERSION=\"${VERSION}\"
-#LDFLAGS = -g ${LIBS}
+CPPFLAGS = -DVERSION=\"${VERSION}\" -D_DEFAULT_SOURCE -DHAVE_SHADOW_H
+CFLAGS = -std=c99 -pedantic -Wall -Os ${INCS} ${CPPFLAGS}
+LDFLAGS = -s ${LIBS}
+COMPATSRC = explicit_bzero.c
+
+# On OpenBSD and Darwin remove -lcrypt from LIBS
+#LIBS = -L/usr/lib -lc -L${X11LIB} -lX11 -lXext -lXrandr
+# On *BSD remove -DHAVE_SHADOW_H from CPPFLAGS
+# On NetBSD add -D_NETBSD_SOURCE to CPPFLAGS
+#CPPFLAGS = -DVERSION=\"${VERSION}\" -D_BSD_SOURCE -D_NETBSD_SOURCE
+# On OpenBSD set COMPATSRC to empty
+#COMPATSRC =