I think, that is what we'll go for rather sooner than later. People already start talking about nano-services when some still haven't fully covered micro-services.

• With containers like Docker or rocket (CoreOS), we're gaining experience in packaging.
• Dependency injection has arrived at many languages.
• In Elixir/Erlang you can already hot rep​lace an application.
• In Node.js (React+Webpack) we have hot module replacement already.
• With amok.js, we can replace functions now.

If we develop such tools a bit further, we may truly gain something like disposable code components.