Rubinius, the implementation of Ruby designed for concurrency with the aim of running Ruby code fast, has reached the major milestone of 2.0 and has just lost its major sponsor.

Rubinius 2.0 is expected to be compatible with the forthcoming Ruby 2.1 which, as Brian Shirai points out in his announcement of the new release means it

"regains a laser focus on supporting the future of Ruby."

He also states:

Starting with 2.0, Rubinius will concentrate on providing exceptional Ruby support for building modern concurrent and distributed applications. Not every legacy Ruby program or quirky Ruby feature will be suitable for Rubinius. Instead, we'll prioritize the performance and stability of concurrent applications to make Ruby competitive with Go, Erlang, Clojure, Scala, and Node.

For this release, which is the first for over two years, Rubinius has been dramatically simplified with major components, like the bytecode compiler, Ruby parser, debugger, etc. have been moved to gems, as has the Ruby standard library, which provides the opportunity to rebuild it in Ruby so that multiple implementations can share it.

The plan is that in future new versions of Rubinius will be released "every week or so" and starting with version 3.0 the goal is to semantically version the Rubinius core. This means using version numbers of the form Major.Minor.Patch where Major is used for incompatible API changes; Minor for added functionality that is backward compatibility and Patch is for bug fixes.

The release of Rubinius 2.0 was greeted with "a tremendous response" from the community, according to Brian Shirai but it has also been marked by the end of Engine Yard's involvement with the project, which dated from 2007. At one time Engine Yard, which sponsors multiple open source projects, has six people working on Rubinius and until last week paid Brian Shirai's salary as a full time worker.

After thanking Engine Yard for its support in a post titled The Once and Future Rubinus, Shirai writes:

The simplest statement about the status of Rubinius is that there are now zero people paid to work on the project.

He sees both advantages and disadvantages of this new state of affairs:

On the one hand, Rubinius is free to aggressively pursue the goals of the project in helping build the future of Ruby. On the other hand, I have significantly less time to devote to the project. While unfortunate, I'm not discouraged. I worked on Rubinius for over a year before Engine Yard hired me and we accomplished a tremendous amount.

We still have numerous things yet to do. Over the past several weeks, I have been working to simplify and focus the project so that all the time we can invest pays significant rewards for developers and businesses. We'll continue to streamline and accelerate delivering value to the people investing their time to use Rubinius.

Rubinius remains an ambitious and forward-looking project - and right now is looking for new contributors with enthusiasm and energy.