[chaostheory]

> i could imagine that a decent full stack dev would rather use the right tool for the right job.

The right tool depends on the requirements. If there's no special requirements then I don't see why javascript can't be a substitute for ruby, python, php, or perl on the backend.

> you would use something like couchdb instead of a relational db

I'm not sure this is a good analogy since javascript (as well as the backend languages that it seeks to substitute for) is more of a general purpose tool, and not a super specialized datastore.