public interface IMessage
{
    Guid Id { get; set; }
}

[Serializable]
public class EntityCreatedMessage : IMessage
{
    public Guid Id { get; set; }
    public Type EntityType { get; set; }
    public Guid EntityId { get; set; }
    public DateTime CreatedTime { get; set; }

    public EntityCreatedMessage(DomainEntity entity)
    {
        EntityType = entity.GetType();
        EntityId = entity.Id;
        CreatedTime = entity.Created;
        Id = Guid.NewGuid();
    }
}

public class RulesEngine : IRulesEngine, Consumes<IMessage>.All
{
    public void Consume(IMessage message)
    {
        ProcessMessage(message);
    }
}