So where does that leave Mozilla's Firefox?
"It's still SpiderMonkey, only substantially more awesome this time," Shaver told InternetNews.com.
Additionally, Mozilla is working on implementing Tamarin technology in its browser by way of the ActionMonkey project. Shaver said the goal of ActionMonkey is to wedge Tamarin into Firefox and make it match Mozilla's existing APIs.
As for how Mozilla stacks up against the new Apple SquirrelFish, Shaver did not deny that the newest contender provides a performance leap.
"They've dropped SquirrelFish in now and got a big speed up there," he said. "We've got more coming on our side. You'll see this leapfrog pattern over and over. We're not going to let anybody slack on that and the other browser vendors need to keep up, too.
Shaver added that he suspects SquirrelFish is faster than SpiderMonkey, though that situation may be likely to change soon.
"We've been in our release lockdown for three months now -- we've got a bunch of stuff queuing up that you'll see in the next few months," Shaver said.
This article was first published on InternetNews.com.