I don't think I've ever seen a J/K/APL job posting, but something tells me that maybe I'm not meant to see one.

But it definitely helps to know it beforehand. APL/J/K job postings are pretty common, although less common than C or Rust postings. Just keep an eye out and you'll see one eventually (and if you do your stuff in public, you'll probably get an offer from one of the usual suspects).

Things I dislike: [...] APL/J/K "culture",

Ow. It cuts like a knife. Right in the heart! Is it the silly jokes? The bad memes in almost every presentation? That we think our approach is better than everyone else's because it produces better code, faster? That we like math?

None of that is exaggerated; I think most of the comparisons usually have a far higher disparity between Iverson's family of languages and everything else.

There are a few very plausible/simple/not at all "out there" reasons for all of this that I'll explain if you want.

This would be for performance issue though. And K, even when interpreted, is still faster than most people's C code because the interpreter does very little and most of the time is spent in optimized loops.

Also, I heard rumors of a JIT (I've seen some of his compilation code and it is pretty amazing and small and even include SSE/AVX optimizations).

I would expect K in particular to benefit immensely from SIMD instructions, yes?

What exactly is it about the "culture" which you dislike?

I love the language but it is, in my opinion, not much more than an academically interesting paradigm now. I agree that every programmer should have non-trivial exposure to these ideas (also Forth and Assembly). And then they should move on.

The language stopped evolving some 20 to 30 years ago. Frankly, I am perplexed as to why it pops-up on HN so much.