No. There's one that made noise about it, but I personally know more than one other from working on their code. Not going to name anyone because I'm not sure

No. There's one that made noise about it, but I personally know more than one other from working on their code. Not going to name anyone because I'm not sure they want their tech decisions publicized. Also some performance-sensitive chunks of wall street itself (depending on how you define "wall street itself". And "performance sensitive" (what I worked on was more "high throughput" than "no pauses".).) run on java. TBF, I write a lot of java, so my perspective is probably biased, but I can assure you, it's out there.