diff --git a/example/echo_server.c b/example/echo_server.c
index 98d5140..c632768 100644
--- a/example/echo_server.c
+++ b/example/echo_server.c
@@ -14,7 +14,7 @@
 //
 // On macOS you may need to add the following flags to your C compiler:
 //
-// 	-framework CoreFoundation -framework Security
+// 	-framework CoreFoundation -framework Security -framework IOKit
 //
 
 #include "../tailscale.h"