diff --git a/include/proto/checks.h b/include/proto/checks.h
index 69c5d2a..042b854 100644
--- a/include/proto/checks.h
+++ b/include/proto/checks.h
@@ -32,6 +32,8 @@
 int start_checks();
 void health_adjust(struct server *s, short status);
 
+extern struct data_cb check_conn_cb;
+
 #endif /* _PROTO_CHECKS_H */
 
 /*