diff --git a/lib/websocket-tracker.js b/lib/websocket-tracker.js
index f84b81b..874490f 100644
--- a/lib/websocket-tracker.js
+++ b/lib/websocket-tracker.js
@@ -17,7 +17,7 @@ try {
   wrtc = null // optional dependency failed to install
 }
 
-var WEBRTC_SUPPORT = !!wrtc
+var WEBRTC_SUPPORT = !!wrtc || typeof window !== 'undefined'
 
 var common = require('./common')