diff -r -u mosquitto-1.6.9/lib/mosquitto.c mosquitto-1.6.9-macos11/lib/mosquitto.c
--- mosquitto-1.6.9/lib/mosquitto.c	2020-02-28 01:49:51.000000000 +0200
+++ mosquitto-1.6.9-macos11/lib/mosquitto.c	2020-11-18 10:36:04.000000000 +0200
@@ -23,6 +23,11 @@
 #include <sys/time.h>
 #include <strings.h>
 #endif
+#ifdef __APPLE__
+#include <mach/mach.h>
+#include <mach/mach_time.h>
+#endif
+
 
 #include "mosquitto.h"
 #include "mosquitto_internal.h"