This is simply not possible with what Glimmer tries to achieve. (Did you even read the article?)
The point I'm trying to make it, there's already a huge amount of churn around the vast amount build tooling needed to write any javascript these days. Part of making a framework with a low barrier to entry is having the build tooling stay out of your way until you're ready to deploy.
I get that's not necessarily Glimmer/Ember's philosophy, I just think it's a shame that using the framework from day 1 requires buying into all of the technology choices around ember-cli.
(Not to mention that the app size zealots will eat you alive)
(No Glimmer there yet, only full Ember, but you can get a feel for what it can do, how it is like, test a things out...)