     // MARK: - Properties
     private let configuration: URLSessionConfiguration
     private let session: URLSession
-    private let queue: DispatchQueue
+    var queue: DispatchQueue = .main
     
     // MARK: - Structs
     private struct Constants {

        
        self.configuration = configuration
        self.session = URLSession(configuration: configuration)
        self.queue = queue
        
        dumpAllConfigurationHeaders()
    }
    
    public init(configuration: URLSessionConfiguration, queue: DispatchQueue = .main) {
        configuration.httpAdditionalHeaders = Constants.defaultHeaders
        
        self.configuration = configuration
        self.session = URLSession(configuration: configuration)
        self.queue = queue
        
        dumpAllConfigurationHeaders()
    }

    // MARK: - Initialiser
    public init(appName: String? = nil,
                headers: [AnyHashable: Any]? = nil,
                timeout: TimeInterval = 60) {
        let configuration: URLSessionConfiguration = .ephemeral
        configuration.httpAdditionalHeaders = Constants.defaultHeaders
        configuration.userAgent(using: appName)
