[ssmoot]

Ruby is glacially slow.

People try really hard to not accept this, and blame "architecture", but yeah, no.

You can read up on templating benchmarks from the very early days of Rails. You can easily spend tens of milliseconds just in template rendering.

The reason ActiveRecord, DataMapper, et all went with multiple Database round-trips had nothing to do with efficiency for the database and everything to do with Ruby's extreme performance deficits. A language so slow that a few thousand objects, with a dozen fields, and a relation, causing a couple million method calls during materialization would bring the interpreter to it's knees.

And now you've filled your response cycle with forced synchronous roundtrips to external services.

You don't even have the option to think about pure architecture. You're working under real constraints that don't just go away. Everything's got 'em, but the point where you have to start worrying about those kinds of issues in your average app in Scala is 100X later.