So why the relative lack of popularity for JRuby/Truffle? I know about startup time and a degraded dev experience (compile/restart server etc is slower). Are these the major pain points?
Or is it simply that most Ruby shops have a good enough performance and they're not looking for anything else?
Very slow startup and the compatibility isn't 100%. You don't get the latest Ruby features and every once in a while, code that would work on CRuby doesn't work out of the box. It's kind of a similar situation with PyPy as far as I can tell. It's been around for a long time but not much adoption.
