title: Is Autofac ContainerBuilder.Build an expensive operation?
body: <p>I'm starting to use Autofac and I can't seem to find an answer to this question.</p>
  
  <p>Also, when should I call ContainerBuilder.Build() ?</p>
  
  <p>After I call the ContainerBuilder.Build() is it possible to register another type or instance?</p>