diff --git a/package.json b/package.json
index f244206..24face4 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "ngx-mqtt",
-  "version": "6.8.3",
+  "version": "6.8.4",
   "description": "ngx mqtt client library",
   "main": "bundles/ngx-mqtt.min.js",
   "module": "./src/index.js",
@@ -32,7 +32,7 @@
   ],
   "license": "MIT",
   "peerDependencies": {
-    "@angular/core": "^6.0.0",
+    "@angular/core": ">6.0.0",
     "rxjs": "^6.2.1",
     "handlebars": "^4.0.11"
   },
@@ -40,6 +40,7 @@
     "@types/node": "10.3.2",
     "ecstatic": ">=3.2.0",
     "ssri": ">=6.0.0",
+    "ngrok": "3.1.0",
     "mqtt": "github:mqttjs/MQTT.js#16848192d5e31918d5b63a697803231caef74a3a"
   },
   "devDependencies": {