diff --git a/bff/ws_proxy.py b/bff/ws_proxy.py
index a245f79..c71188d 100644
--- a/bff/ws_proxy.py
+++ b/bff/ws_proxy.py
@@ -3,6 +3,7 @@
 import asyncio
 import json
 import logging
+import secrets
 
 from fastapi import APIRouter, WebSocket, WebSocketDisconnect
 import websockets
@@ -32,10 +33,11 @@ async def ws_proxy(ws: WebSocket, token: str = ""):
 
     try:
         async with websockets.connect(TRACKER_WS_URL) as tracker_ws:
-            # Send auth to tracker on behalf of user
+            # Auth to tracker with on_behalf_of so Tracker uses user's slug
             auth_msg = json.dumps({
                 "type": "auth",
                 "token": TRACKER_TOKEN,
+                "on_behalf_of": user_slug,
             })
             await tracker_ws.send(auth_msg)