public static class UnityContainerExtensions
{
    public static void AssertMappingsAreValid(this IUnityContainer container)
    {            
        foreach (var registration in container.Registrations)
        {
            container.Resolve(registration.RegisteredType, registration.Name);
        }
    }
}

using System;
using System.Collections.Generic;
 
namespace UltraLight
{
    public class RegistrationInfo
    {
        private readonly object _lock = new object();
        private readonly UltraLightContainer _container;
        private readonly Type _concrete;

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
 
public class SimpleContainer 
{
    readonly List<ContainerEntry> entries = new List<ContainerEntry>();
 
    public void RegisterInstance(Type service, string key, object implementation)