may I ask why remove TruffleRuby? That is a huge PR :)

@claudiug this mailing list post explains the reasons http://lists.ruby-lang.org/pipermail/jruby/2017-January/000511.html

TruffleRuby doesn't have any source code dependencies on JRuby anymore and hasn't for a while. We're having to tidy up our code base quite a bit in order to prepare for an ahead-of-time compiled (no JVM required) version of TruffleRuby that we are going release soon, and with both of those things it seemed time to start to develop in a separate repo.

@chrisseaton thx for the quite fast reply.
AOT for ruby? wow

It's AOT for the Java program that implements an interpreter for Ruby, not AOT for the Ruby program. It's confusing I know.

It allows us to build a single, statically linked truffleruby executable that doesn't need a JVM to run, so much like the ruby executable you get with MRI. This reduces startup time by orders of magnitude, memory footprint, and deployment issues.