alt Hacker NewsFor pretty much everything. My terminal is in Ruby, with a Ruby font renderer, running Ruby shell, and my editor is in Ruby, my window manager, my file manager.
(Yes, I'm taking it a bit far; my prototype Ruby compiler is self-hosting finally, so I guess sometime in the next 20 years I'll end up booting into a Ruby kernel for no good reason...)
I really like Ruby. It had a formative impact on my young programmer self, particularly the culture. So much joyful whimsy.
But like... something like a font renderer in Ruby? The thing that is incredibly cache sensitive and gets run millions of times per day on a single machine? The by far slowest step of rendering any non-monospaced UI?
The Earth is weeping my brother.