A developer who uses crystal? Like a builder who uses a hammer is not a hammer-user ;)
EDIT: Wow that took a long time to realize what you meant...haha no, truly not good, and thinking about it my comment "A developer who uses crystal?" is now terrible too.
As someone from the US state of Michigan that has at least two competing demonyms, I actually find the idea of everyone using a different form based on preference to be charming.
Man, there have to be better alternatives than this.
Did you try “crystacean?” Chuckles in .rs.