diff --git a/SocketIO-MacTests/SocketEngineTest.swift b/SocketIO-MacTests/SocketEngineTest.swift
index 317281e..90ef328 100644
--- a/SocketIO-MacTests/SocketEngineTest.swift
+++ b/SocketIO-MacTests/SocketEngineTest.swift
@@ -15,8 +15,8 @@ class SocketEngineTest: XCTestCase {
 
     override func setUp() {
         super.setUp()
-        client = SocketIOClient(socketURL: NSURL())
-        engine = SocketEngine(client: client, url: NSURL(), options: nil)
+        client = SocketIOClient(socketURL: NSURL(string: "http://localhost")!)
+        engine = SocketEngine(client: client, url: NSURL(string: "http://localhost")!, options: nil)
         
         client.setTestable()
     }
diff --git a/Source/SocketEngine.swift b/Source/SocketEngine.swift
index 83be7b3..791f016 100644
--- a/Source/SocketEngine.swift
+++ b/Source/SocketEngine.swift
@@ -47,8 +47,8 @@ public final class SocketEngine: NSObject, SocketEnginePollable, SocketEngineWeb
     public private(set) var session: NSURLSession?
     public private(set) var sid = ""
     public private(set) var socketPath = "/engine.io/"
-    public private(set) var urlPolling = NSURL()
-    public private(set) var urlWebSocket = NSURL()
+    public private(set) var urlPolling = NSURL(string: "http://localhost?default=")!
+    public private(set) var urlWebSocket = NSURL(string: "http://localhost?default=")!
     public private(set) var websocket = false
     public private(set) var ws: WebSocket?