public ICollection <DependentRegistration> GetRegistrations(IEnumerable <Assembly> assemblies = null) { assemblies = assemblies ?? GetAssemblies() .Where(a => a.GetCustomAttribute <DiscoverableAssemblyAttribute>() != null); var registrations = _dependentRegistrationFactory.CreateDependentRegistrations ( assemblies ); _registrationSorter.Sort(registrations); return(registrations); }