diff --git a/apollo/interfaces/azure/host.json b/apollo/interfaces/azure/host.json
index 88a6fb7..2c1bb24 100644
--- a/apollo/interfaces/azure/host.json
+++ b/apollo/interfaces/azure/host.json
@@ -9,7 +9,7 @@
   },
   "extensionBundle": {
     "id": "Microsoft.Azure.Functions.ExtensionBundle",
-    "version": "[3.*, 4.0.0)"
+    "version": "[4.0.0, 5.0.0)"
   },
   "extensions": 
   {
@@ -18,4 +18,4 @@
         "routePrefix": ""
     }
   }  
-}
\ No newline at end of file
+}