rubinius

A few points: a) The ruby standard library is written in Ruby and is actually surprisingly well-behaved from a threading perspective. The code is not super-pretty, but it uses appropriate locking strategies and has been well-tested in threaded environments. All three major implementations (JRuby, MRI and Rubinius) share the vast majority of the Ruby standard library, so if JRuby works, Rubinius will work. 2) For the part of MRI written in C (which Rubinius calls the "kernel"), Rubinius has reimplemented the entire thing mostly in Ruby with some primitives. Since they own that code, it is their responsibility to define its semantics when run in parallel. 3) Rubinius implements its locking classes (like Mutex and ConditionVariable, see https://github.com/evanphx/rubinius/blob/master/lib/thread.r...) on top of its own low-level Channel imple

One other thing a lot of people don't know about Rubinius is that its fundamental concurrency primitive is Rubinius::Channel, similar to channels in Go. For example, see Rubinius' implementation of class Mutex: https://github.com/evanphx/rubinius/blob/master/lib/thread.r... Quoth MenTaLguY: MenTaLguY: Channels are the basic communication primitive in Rubinius; everything else is implemented atop them. The fundamental concurrency model is more or less the asynchronous pi calculus minus replication and a few common extensions like non-deterministic choice (which potentially requires channel operations to be centrally arbitrated). I advocated pi calculus channels because of their simplicity, which generally translates to performance and maintainability. http://www.infoq.com/articles/actors-rubinius-interview

That's not what the Rubinius team is saying. http://news.ycombinator.com/item?id=631646 I'm not qualified to judge how much progress is being made, but casting an eye briefly over the commit log, there certainly seems to be plenty of activity. http://github.com/evanphx/rubinius/commits

We have a branch of Rubinius that is compiling ruby to rubinius bytecodes and then transforming that into LLVM bitcode for native compilation. It is still in the early stages but it already giving big speed improvements. http://github.com/evanphx/rubinius/commits/cpp

I'd recommend github for source hosting. I've got multiple open source projects that I run or use that use github for scm and use lighthouseapp.com for ticketing. These are fairly large OSS projects with many many contributors and it works great. http://github.com/wycats/merb-core/tree/master and http://github.com/evanphx/rubinius/tree/master as well as a bunch of other smaller oss projects. Both github and Lighthouse will give free accounts to open source projects.