News

Adobe Takes Flex SDK Open Source

• By Chris Kanaracus
• April 27, 2007

In a major salvo that ups the stakes in the emerging battle for mindshare among developers and architects building rich Internet applications (RIAs), Adobe said it is releasing its Flex SDK into the open-source community.

The move comes less than two weeks after Microsoft unveiled Silverlight, formerly known as Windows Presentation Foundation Everywhere, or WPF/E. Silverlight is the company's cross-platform browser plug-in for rich media that some have dubbed a "Flash Killer."

The timing of Adobe's announcement comes just days before Microsoft's MIX07 conference in Las Vegas, where Microsoft is expected to reveal extensive details about Silverlight-based development over the course of three days.

Adobe said in a statement that the open source Flex SDK and documentation will be available under the Mozilla Public License. The company intends to release all components of the Flex SDK required to develop Flex apps, a list that includes Java source code for the ActionScript and MXML compilers, the ActionScript debugger and ActionScript libraries. However, Adobe said its Eclipse-based IDE, Flex Builder, doesn’t factor into the open-source release.

Adobe's Flash enjoys a market penetration often pegged in the 90-plus percent range, but Microsoft has a massive user base in place through its browser and operating system, which it can leverage to distribute and foster Silverlight. Therefore, every move by both camps counts, suggested Forrester Research Analyst Jeffrey Hammond.

"As both Apollo and Silverlight emerge as RIA development platforms, wooing the open-source community gives Adobe a potential advantage in the race toward ubiquity, an advantage they will need to counter the continued market share leadership of IE and Microsoft’s desktop OS," Hammond wrote in an e-mail.

Hammond put Thursday's news in context against Adobe's decision last year to give the source code for the ActionScript Virtual Machine to the Mozilla Foundation as part of an open-source project known as Tamarin. (Developers already working on Tamarin-based projects will be able to use the open-source Flex SDK for compiling and debugging, Adobe said.)

Hammond says now Flex and Tamarin are positioned to become "the Mozilla language and framework of choice for cross-platform RIA development that includes Linux."

Burton Group research director Peter O'Kelly calls Adobe's move "a subtly significant strategic shift .... It’s likely to make Flex a viable choice in some important domains in which developers otherwise would have gone with an open-source alternative (e.g., OpenLaszlo)," he wrote in an e-mail to Redmond Developer News. "Overall, it's likely to accelerate what’s already impressive momentum for Flex."

One difference between the Flex SDK announcement and Tamarin is the fact Adobe says it plans to sponsor and host the Flex project infrastructure. The Flex SDK will also remain available under a commercial license, and the two versions will be as similar as possible, according to Adobe.

Thursday's announcement is only the latest in a series of moves by Adobe to foster development around its RIA technologies. The company in March released an alpha of "Apollo," a cross-platform runtime capable of building and deploying RIAs on the desktop.

Apollo will let users work with Internet apps without launching a browser. If content is changed or added offline, it can be synced back up with the app once a user goes online.

The company has said users eventually will be able to drag and drop files and assets into Apollo apps. Future versions of Apollo will support Linux and work with mobile technologies, as well as include more support for AJAX, according to Adobe.