In an interview with eWEEK Feb. 5, Lam said Kelly approached him after the conference was over “to talk about what he wants to do next. I think he made up his mind after learning more about the DLR at Lang.NET. We talked about areas in IronRuby where we thought we could use his help, and his interest really is much more from an academic point of view versus shipping a product. In the end, it was kind of strange that a university was involved in producing a production-quality compiler."

Kelly said as much in his e-mail. "As a researcher, my prime interest is not in developing products, but in developing innovative new ideas and having an impact by having those ideas used in the real world," he said.

Kelly also said that Microsoft did not try to influence his decision.

“Joining forces lets us avoid duplicating effort,” Lam said. “More people working in parallel on libraries means that folks will get a working Ruby on .Net that runs real programs sooner."

Both Lam and Kelly said a core goal of both projects is to get the popular Ruby on Rails framework running on .Net.

Meanwhile, on the same Ruby.Net discussion group thread, some Ruby.Net supporters said that while they respect Kelly's decision, they do not see reason to kill the project.

"I still believe that there is room in the world for both a statically-compiled Ruby and a dynamically-interpreted Ruby on the CLR, with Ruby.NET representing the former and IronRuby the latter," said Ted Neward, founder of Neward & Associates.

“There is a clean separation between what Ruby.NET can offer the .NET developer ‘right now’ and what IronRuby ‘will not’ offer the .NET  developer in the near term future. As such this is one area that I believe should be the core focus of the Ruby.NET project moving forward,” said M. David Peterson, co-founder and chief architect at 3rd&Urban.