diff --git a/uloop.c b/uloop.c
index e9f8d52..568dcd6 100644
--- a/uloop.c
+++ b/uloop.c
@@ -46,7 +46,7 @@
 #endif
 #define ULOOP_MAX_EVENTS 10
 
-struct uloop_timeout *first_timeout;
+static struct uloop_timeout *first_timeout;
 static int poll_fd;
 bool uloop_cancelled = false;