The software developer said it was switching to a 'sprint' cycle because it decided it not only needs a way to be more nimble but it had "a lot of great improvements we want to do every week and every month", according to Firefox architect Vlad Vukicevic.
"That was the thinking behind the 'sprint' development: that we have a bunch of projects that we assign to one or two people, who then have two to three weeks to maybe finish [the feature] or at least get some data on it," Vukicevic said.
"Then we can decide if we want to do another sprint."
The change means that the next two Firefox upgrades will be minor updates that are pushed through development in a matter of a few months, a big difference from the last two versions of the browser, which included major changes to the interface or the underlying technology, or both.
Here comes Firefox 3.6... and 3.7
According to Mozilla's current schedule , for example, Firefox 3.6, the follow-on to June's version 3.5, will ship in the October-to-November time frame. The next update, Firefox 3.7, is now set to release around March 2010.
The major update, tentatively tagged as Firefox 4.0, won't launch until late 2010, perhaps in the October-to-November time period.
Even with a roadmap, however, Vukicevic said a lot remains provisional. "The only thing we're certain of is that we'll do at least one release a year from now on," he said. "But whether there's a second release this year, for example - that's up in the air."
Picking up the development pace came out of Mozilla's experience with Firefox 3.0 and 3.5. "Back when we were doing Firefox 3.0, we were adding so much new stuff that it was very hard to wrap up the release," admitted Vukicevic.
Competition heats up
Although Vukicevic denied that the shorter schedules were a direct response to heated competition among browser makers, his explanation hinted as much. "The schedules are driven by (the fact) that we want to get new features into the hands of our users as fast as possible," he said.
Mozilla will also provide the Firefox 3.6 and 3.7 upgrades in different ways to previous updates, said Vukicevic. Rather than make a big deal out of those updates, and offer them via its traditional upgrade process, which extends over several months, Mozilla will probably push them to users with the same kind of update method it uses for security fixes.
In that case, users will be notified within 48 hours that the update is available.
"We want to focus on the large updates," said Vukicevic, "and get users excited bout the major updates. The minor updates, though, we want to make them as transparent as possible."
Among the changes planned for Firefox 3.6, Mozilla has highlighted several, including 'Personas' or lightweight themes that don't require a browser restart; more performance improvements to TraceMonkey; support for Windows 7 features such as 'Aero Peek' and a speed boost to Firefox's location bar, which does automatic lookups in the browser's history database.
Firefox 4.0, on the other hand, will be the first Mozilla browser to include Electrolysis, a project that aims to separate each tab and add-on to its own process, which will prevent the application from crashing when a website, web application or extension fails. Google uses that multi-process model in its Chrome browser.
Mozilla has also recently posted information on its website about the user interface changes it wants to make in the Windows versions of Firefox 3.7 and 4.0.
Firefox 3.6 is available now as an alpha , which Mozilla issued more than a month ago. The company intends to ship the first, and only, beta version of the November update later this month.