A simple NRack app [https://github.com/kevinswiber/NRack]

Config.cs

using System;
using NRack.Auth;
using NRack.Configuration;
using NRack.Helpers;

namespace NRack.Example.AspNet
{
    public class Config : ConfigBase
    {
        public override void Start()
        {
            Use<CustomAuthHandler>()
                .Run(new MyApp()));
        }
    }
}

MyApp.cs

using System.Collections.Generic;
using NRack.Helpers;

namespace NRack.Example.AspNet
{
    public class MyApp : ICallable
    {
        public dynamic[] Call(IDictionary<string, dynamic> environment)
        {
            return new dynamic[] { 200, new Hash{{"Content-Type", "text/html"}}, "<h1>Hello, World!</h1>"};
        }
    }
}