alt Hacker NewsI surely don't want a fast compiled Ruby for the tasks I would use crystal for though.
Like every one else I also used ruby for almost everything back then, usually some hundred of lines or less for processing stuff. but for tasks that run for several hours using ruby was a frustrating experience. slowness and memory consumption aside, the duck typing system and lazy evaluation of method meaning you can run to typo after hours of running session. sure, you can fix it by write the code more carefully, running smoke tests beforehand and other stuff, but it still a chore, and when you write code all days it makes you sloppier.
having a strong typed compiled language helps it immensely, and with crystal you don't have to sacrifice the easiness of programming. and you can compile it to a portable binary and run it everywhere, no need to reinstall a huge toolchain again. (yeah rust or go can also do that, but not for ruby level expressioness language)
I'm sure crystal is not the ideal language for everything you want to use, and ruby is still helpful for what you use daily. but for some tasks, crystal surely has it own advantages. you can write very capable CLI programs without have to install a single library!
You're free to like Crystal of course, but for me even for long running tasks (almost my entire desktop, including my wm, terminal, editor are Ruby - I still use Ruby for almost everything; if anything, for more than ever), the Ruby ecosystem beats the steadily diminishing performance gap between MRI and an AOT compiled language to the extent that even going to TruffleRuby where I could keep almost all of my code, is rarely worth it for me.
But my main point was that people who do want a fast Ruby should be aware that Crystal isn't a Ruby in any meaningful sense - if you like Crystal for Crystal, by all means use it.