foo.js

watchFor("[data-react-class='Uploader']", function() {
  import(/* webpackChunkName: "uploader" */ "components/uploader").then(
    module => {
      exposeComponents({ Uploader: module.default });
    }
  );
});

watchFor("[data-react-class='AudioEditor']", function() {
  import(/* webpackChunkName: "AudioEditor" */ "components/audio_editor").then(
    module => {
      exposeComponents({ AudioEditor: module.default });
    }
  );
});

watchFor("[data-react-class='MidrollEditor']", function() {
  import(/* webpackChunkName: "MidrollEditor" */ "components/midroll_editor").then(
    module => {
      exposeComponents({ MidrollEditor: module.default });
    }
  );
});