ConNegModule.cs

namespace NancyConNegDemo
{
    using Extensions;
    using Models;
    using Nancy;

    public class ConNegModule : NancyModule
    {
        public ConNegModule() : base("/conneg")
        {
            Get["/"] = x =>
            {
                var model = new UserModel(Context.Items["username"].ToString());

                I.RespondTo(ContentTypes.Html).WithView("MyView")
                 .RespondTo(ContentTypes.Xml)
                 .RespondTo(ContentTypes.Json)
                 .UsingModel(model);
            };
        }
    }
}