IBM is losing a leader in the area of aspect-oriented programming to an open-source startup.

Adrian Colyer, a senior member of the technical staff at IBM's Hursley, England facility, said he resigned his position with the systems giant to join London-based Interface21, a startup focusing on the open-source Spring framework for building Java applications.

Colyer will assume the position of chief scientist at Interface21.

According to Xerox Palo Alto Research Center documents describing AOP, "AOP introduces a new unit of modularity, called an aspect, that is not present in other types of programming. Aspects are suited for modularizing crosscutting concerns, which are difficult to address in OO (object-oriented) and procedural languages."

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Colyer is the head of the AspectJ project, an open-source project delivering a framework for building aspect-oriented applications.

Colyer said AspectJ is the premier AOP (aspect-oriented programming) platform. AspectJ is the result of a merger between AspectJ technology, supported by IBM and AspectWerkz technology supported by BEA Systems Inc.

Up to now, Colyer led IBM's foray into AOP and helped support other groups throughout the company that were interested in the technology, he said.

"I lead the AspectJ project," Colyer said in an interview with eWEEK.com. "That's one of the wonderful things about open source. I can change employers but still keep right on doing that. I'll be pushing both the Spring project and the AspectJ project under the roof of one company, which is Interface 21. That's quite an exciting marriage there."

Indeed there are three leading AOP projects out right now, Colyer said.

"There are basically three key players now in the AOP space," he said. "You have had AspectJ and AspectWerkz and we merged them together and are about to deliver AspectJ 5, and BEA contributes to that project as well as IBM. That's probably the long established leader.

"Then there's Spring AOP, which said we'll just do the very basic things like help you configure your beans [JavaBeans], but we're not going to go any further than that," Colyer added. "And if you want to go further than that we'll make it easier for you to use AspectJ. And the other option is JBossAOP, which has got some good stuff and focuses on writing a lot of aspects as well as building the framework.

"But really the question there is can they take JBossAOP and move it up into the JBoss server and get it used outside of that environment a little bit more? I don't see the momentum behind it that the others have got at the moment."

Colyer said he submitted his resignation to IBM Monday and plans to begin working at Interface21 next month.

He said he could have continued to work on Spring AOP at IBM, "but the freedom to contribute more heavily to the Spring AOP code base would be a bit more restricted at IBM," he said. "But I'll still be heading the AspectJ project. But the time that I would spend working with teams around the [IBM] corporation I'll now be using to work on Spring AOP with clients around the world."

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"I think this is a significant announcement for AOP in general," said Rod Johnson, founder of Spring and Interface21. "Part of what he [Colyer] will be doing is laying out a comprehensive roadmap for AOP, from Spring AOP through to enhanced Spring/AspectJ integration.

"We believe that this will help to provide users with clarity in the AOP space, and that it will help further mainstream adoption of AspectJ. By the way, the AspectJ 5 release is a major milestone, fully incorporating the results of the merger with AspectWerkz and many new features."

Colyer said he is excited about the momentum Spring has attained. "Spring is getting a lot of traction and Spring AOP is working quite well," he said.

"The opportunity arrived to join the other side of the fence and work with Interface21. The thing I really like about Spring is that it's got a really pragmatic focus. That's really what sets it apart.

"It's about being a simple pragmatic thing that works," he added. "And I think that's actually a great way to be pitching aspect-oriented programming for the next little while, because there's going to be a lot of hype and backlash as the new technology breaks."

This article was originally published on eWEEK.com.