/// <summary>
        /// Parse an incoming service descriptor instance &
        /// convert it into a useable Guppy TypeFactory/ServiceConfiguration
        /// </summary>
        /// <param name="descriptor"></param>
        /// <param name="services"></param>
        internal static void ConvertServiceDescriptor(this ServiceDescriptor descriptor, ServiceCollection services)
        {
            var implementationType = descriptor.ImplementationType ?? descriptor.ServiceType;
            var key   = ServiceConfigurationKey.From(descriptor.ServiceType);
            var count = services.ServiceConfigurations.Count(c => c.Key == key);

            services.RegisterTypeFactory(
                type: implementationType,
                typeImplementation: implementationType,
                method: descriptor.CreateFactoryMethod(),
                priority: count);

            services.RegisterServiceConfiguration(
                key,
                descriptor.Lifetime,
                implementationType,
                ServiceConfigurationKey.From(implementationType).Yield(),
                priority: count);
        }