title: What is the namespace for IService interface?
body: <p>I am learning ServiceStack and developing simple demo for helloworld, but could not find namespace for <code>ISservice</code> interface, my code as per below:</p>
  
  <pre><code> public class Hello
  {
      public string name { get; set; }
  }
  public class HelloResponse
  {
      public string Result { get; set; }
  }
  
  public class HelloService :  **IService**&lt;Hello&gt;
  {
      public object Execute(Hello request)
      {
          return new HelloResponse { Result = "Hello" + request.name };
      }
  }
  
  public class HelloAppHost : AppHostBase
  {
      public HelloAppHost() : base("Hello Web Services", typeof(HelloService).Assembly) { }
      public override void Configure(Funq.Container container)
      {
          Routes.Add&lt;Hello&gt;("/hello")
              .Add&lt;Hello&gt;("/hello/{Name}");
  
      }
  }
  </code></pre>
  
  <p>Can anyone please tell me what namespace or DLL I need to add for <code>IService</code> interface?</p>