Correct. We do not currently support RubyGems. It's something we're working towards, but it's a fairly complex project and not having OpenSSL support currently limits the ability to install gems quite a bit. However, we do ship with a tool that will install gems using JRuby without Truffle and then running your script with a the $LOAD_PATH set up appropriately. Please see:

https://github.com/jruby/jruby/blob/master/lib/ruby/truffle/...

Re: Rails ... there's still a fair bit of work involved there. We've been working on passing all the ActiveSupport tests (we're currently at 99%), as that's a core dependency. We haven't looked much into the other gems. Things like ActiveRecord simply won't work since we currently don't run C or Java extensions. I think it's a bit more likely we'll start with a custom driver of some sort with an ActiveModel front-end. I strongly suspect the asset pipeline and Spring will present problems, as well. The rest of Rails should pull together somewhat quickly and that's a big goal for us in 2016.