diff --git a/main/include/wifi_connection.h b/main/include/wifi_connection.h
index 040e949..782e48d 100644
--- a/main/include/wifi_connection.h
+++ b/main/include/wifi_connection.h
@@ -2,6 +2,7 @@
 
 #include <stdbool.h>
 #include <stdint.h>
+#include <stddef.h>
 
 #include "esp_wifi.h"