diff --git a/examples/regex_patterns/build_opt.h b/examples/regex_patterns/build_opt.h
new file mode 100644
index 0000000..f597851
--- /dev/null
+++ b/examples/regex_patterns/build_opt.h
@@ -0,0 +1 @@
+-DASYNCWEBSERVER_REGEX=1
\ No newline at end of file