How do you switch languages during a job search? Are you avoiding companies with language requirements (four years Ruby)? Do you run into language/framework tests and/or homework assignments in languages you are unfamiliar with?
That still takes time. If someone is already experienced in an (complex) ecosystem, he or she will be way more effective in it, than someone who has just general skills. I guess I am a very good problem solver. But if I suddenly would have to do a C++ project with all its footguns, I am not aware of (last time I coded in C++ was in university)? I would suck in it for quite a while. This would not be effective at all, unless I would want to change my skillset to the C++ ecosystem.
Yes. I want to work somewhere that shows they're committed to the long term, not somewhere that's focused on how much I'll get done in my first week.
I'm not sure. I'd guess very few companies that hire more than 20 devs a year would have any language requirements. But I don't know what % of jobs are at companies of that size.
As opposed to companies which consider them as glorified factory workers, who are insufferably hard to manage and monitor.
I'm currently working with RoR, which I'd never used before, and what matters is that I know algorithms, SQL beyond ORM, how to write code which won't be a nightmare to maintain in a couple of years, etc. All those skills are the same in Rails, in Django, in C++.
Prior experience is almost a curse these days. I learned Go by having the Go team review every one of my CLs for a year. Now I do Go code reviews and think "that simply isn't done, I would never have been allowed to check that in", but often have a hard time supporting my arguments. (When Effective Go, Code Review Comments, and Test Comments fail me, I usually resort to snippets from the standard library. "This pattern appears 0 times in the standard library, I don't think we should use it." It's a lot of work, but I will say that a few things I thought were simply never done are actually done. And that's my standard; I hate it, but Go itself did it to implement Go, so you can too.)
Side rant: I guess the Go team stopped doing this. Read Kubernetes for the current state of Go at Google. Wow.