Working in Ruby is fine if you’re just adding a feature on top of the pile of features. All you have to do is add some unit tests, make sure the old ones pass,

Working in Ruby is fine if you’re just adding a feature on top of the pile of features. All you have to do is add some unit tests, make sure the old ones pass, and run away. But anything else is impossibly difficult. No, not "impossibly difficult". Just not as effortless as you'd like it do be. Which fortunately makes it easy to discount the the rest of the article for what it is - needlessly charged hyperbole and (gross) oversimplification of what should be viewed as a substantially more complex set of tradeoffs. Or that is to say: a rant.