     
     private func objectMapperResponseHandler(data: AnyObject) {
         
-        let json: NSDictionary = NSJSONSerialization.JSONObjectWithData(data as! NSData, options: NSJSONReadingOptions(0), error: nil) as! NSDictionary
+        let json: AnyObject? = NSJSONSerialization.JSONObjectWithData(data as! NSData, options: NSJSONReadingOptions(0), error: nil)
             
         let repo = Mapper<RepoObjectMapper>().map(json)
             

    }
    
    func requestFor(library: Library) {
        
        Alamofire.request(.GET, "https://api.github.com/repos/hkellaway/swift-json-comparison", parameters: nil).response { (request, response, data, error) in
            
            if let e = error {
                println("ERROR = \(e)")
            }
            


class ViewController: UIViewController {

    enum Library {
        case Argo
        case JSONJoy
        case ObjectMapper
        case SwiftyJSON
    }
    
    override func viewDidLoad() {
