[haskellandchill]

Not true. While it's harder, you can stack shift. I've done Ruby/Rails, Python/Django, and JavaScript/React and treated them as interchangeable. I might be rejected in some resume screens here and there but once talking I make it clear I'm comfortable with the target tech stack and it has never been an issue.

[danjac]

"Once talking" is the problem. You have to get your resume picked out of the pile so you get to talk to a real person.