diff --git a/src/schema/Identify.ts b/src/schema/Identify.ts
index 65ef9c89..eaa2ff80 100644
--- a/src/schema/Identify.ts
+++ b/src/schema/Identify.ts
@@ -16,7 +16,9 @@ export const IdentifySchema = {
 		$browser_version: String,
 		$os_version: String,
 		$referrer: String,
+		$$referrer: String,
 		$referring_domain: String,
+		$$referring_domain: String,
 		$referrer_current: String,
 		$referring_domain_current: String,
 		$release_channel: String,
diff --git a/src/util/setHeartbeat.ts b/src/util/setHeartbeat.ts
index a59dd251..9f88b481 100644
--- a/src/util/setHeartbeat.ts
+++ b/src/util/setHeartbeat.ts
@@ -1,3 +1,4 @@
+import { CLOSECODES } from "./Constants";
 import WebSocket from "./WebSocket";
 
 // TODO: make heartbeat timeout configurable
@@ -5,6 +6,6 @@ export function setHeartbeat(socket: WebSocket) {
 	if (socket.heartbeatTimeout) clearTimeout(socket.heartbeatTimeout);
 
 	socket.heartbeatTimeout = setTimeout(() => {
-		return socket.close(4009);
+		return socket.close(CLOSECODES.Session_timed_out);
 	}, 1000 * 45);
 }