Deno is something in javascript-land that just popped up (I'm not sure what exactly what it is, since I haven't keep up about JS ecosystem since friday and everything has changed), so yeah it's a joke that they require 5 years of experience in it.

Unless they're trying to catch a time-traveler.

IIRC Deno is a new JS runtime built by the creator of Node and written in Rust that pledges to resolve some of the hairier issues with Node. It’s actually one of the JS projects I’m most looking forward to maturing.

Did you read his job opening? There's absolutely no part of it that's not sarcasm

Ironically, you're assuming that he knows what Deno is and how recent it is.

sometimes sarcasm is like well written code self explaining :-)