diff --git a/package.json b/package.json
index 0f9261059..712dc0350 100644
--- a/package.json
+++ b/package.json
@@ -82,13 +82,14 @@
   },
   "devDependencies": {
     "@types/node": "^10.0.0",
+    "@types/ws": "^8.2.0",
+    "aedes": "^0.42.5",
     "airtap": "^3.0.0",
     "browserify": "^16.5.0",
     "chai": "^4.2.0",
     "codecov": "^3.0.4",
     "end-of-stream": "^1.4.1",
     "global": "^4.3.2",
-    "aedes": "^0.42.5",
     "mkdirp": "^0.5.1",
     "mocha": "^4.1.0",
     "mqtt-connection": "^4.0.0",
diff --git a/types/lib/client.d.ts b/types/lib/client.d.ts
index 7821a96d7..c439fe89e 100644
--- a/types/lib/client.d.ts
+++ b/types/lib/client.d.ts
@@ -8,7 +8,7 @@ import {
   IClientReconnectOptions
 } from './client-options'
 import { Store } from './store'
-import { Packet, IConnectPacket, IPublishPacket, IDisconnectPacket, QoS } from 'mqtt-packet'
+import { Packet, IConnectPacket, IPublishPacket, IDisconnectPacket, QoS, IConnackPacket } from 'mqtt-packet'
 
 export interface ISubscriptionGrant {
   /**
@@ -66,7 +66,7 @@ export interface ISubscriptionMap {
   }
 }
 
-export declare type OnConnectCallback = (packet: IConnectPacket) => void
+export declare type OnConnectCallback = (packet: IConnackPacket) => void
 export declare type OnDisconnectCallback = (packet: IDisconnectPacket) => void
 export declare type ClientSubscribeCallback = (err: Error, granted: ISubscriptionGrant[]) => void
 export declare type OnMessageCallback = (topic: string, payload: Buffer, packet: IPublishPacket) => void