diff --git a/include/types/checks.h b/include/types/checks.h
index 29d0ebd..49e4ed6 100644
--- a/include/types/checks.h
+++ b/include/types/checks.h
@@ -225,6 +225,7 @@
 	int alpn_len;                  /* ALPN string length */
 	uint16_t options;              /* options when setting up a new connection */
 	uint16_t port;                 /* port to connect to */
+	struct sample_expr *port_expr; /* sample expr to determine the port, may be NULL */
 	struct sockaddr_storage addr;  /* the address to the connect */
 };