After a marriage lasting almost 12 years, Google has decided to bid farewell to the WebKit rendering engine, upon which its open-source Chromium browser project is based. In its place, Google welcomes Blink, a new open-source rendering engine that’s based on WebKit, which from now on will become the driving force behind its popular Chrome browser.

Explaining what prompted the move, Google software engineer Adam Barth writes in a blog post that although WebKit is lightweight and powerful, Chromium employs a “different multi-process architecture than other WebKit-based browsers, and supporting multiple architectures over the years has led to increasing complexity for both the WebKit and Chromium projects.”

And so Google has decided to do away with WebKit and develop Blink, which is essentially a forked version of the former.

Barth points out that the decision wasn’t an easy one to make.

“We know that the introduction of a new rendering engine can have significant implications for the Web. Nevertheless, we believe that having multiple rendering engines—similar to having multiple browsers—will spur innovation and over time improve the health of the entire open web ecosystem.”

Google’s decision is important because WebKit has been, up until now anyway, one of the “big three” rendering engines alongside Microsoft’s Trident (used in Internet Explorer) and Mozilla’s Gecko (used in Firefox). WebKit is employed by both Google Chrome and Apple’s Safari browser, not to mention several lesser known browsers like the Yandex browser and Comodo Dragon, and the majority of mobile web browsers like Dolphin Browser and Boat. WebKit itself was derived from the old KHTML rendering engine that powered the old Konquerer browser on Linux desktops. It’s source code was later modified by Apple and given its new name.

For Google Chrome users, the change probably won’t cause much of a difference to their browsing experience. After all, Blink is just a fork of WebKit and many of its fundamental aspects will remain the same. Things won’t change that much for developers either, insists Barth. “The bulk of the initial work will focus on internal architectural improvements and a simplification of the codebase,” he wrote.

Barth adds that Google intends to collaborate with other browser makers to ensure that the transition goes as smoothly as possible:

“We’ve set strong guidelines for new features that emphasize standards, interoperability, conformance testing and transparency.”

Interestingly, Google’s decision to swap WebKit for Blink comes just weeks after Opera announced that it was doing away with its own Presto rendering engine in favor of the former. Opera’s Håkon Wium Li justified that move, saying that “it makes more sense to have our experts working with the open source communities to further improve WebKit and Chromium, rather than developing our own rendering engine further.”

Opera hasn’t commented officially on Google’s decision, but Bruce Lawson, an open web standard evangelist for the company, said on his personal blog that “Opera will be contributing to Blink” in the future. If Opera does indeed follow suit, that would leave Apple’s Safari as the only major browser still using WebKit.

Meanwhile, Google’s announcement follows a statement this morning that Mozilla is collaborating with Samsung to create a new browser engine called Servo, which will “rebuild the Web browser from the ground up on modern hardware, rethinking old assumptions along the way.”