Other browser vendors needed to overhaul their interpreters to compete. Apple developed the Nitro engine for its Safari browser, which had 30% better performance than its predecessor. Mozilla leveraged portions of Nitro to improve its own SpiderMonkey engine. Opera replaced its interpreter with the Carakan engine, which was twice as fast in some cases.
- SpiderMonkey is developed by Mozilla for use in Firefox and its forks. The GNOME Shell uses it for extension support.
- Chakra is the current engine of the Microsoft Edge browser, forked from the same-named engine of Internet Explorer. However, Microsoft is now rebuilding Edge as a Chromium-based browser, so it will be using V8 instead of Chakra. Internet Explorer continues to use its version of Chakra.
- Shankland, Stephen (2008-09-02). "Speed test: Google Chrome beats Firefox, IE, Safari". CNET Business Tech. CBS Interactive. Retrieved 2010-06-28.
- "Big browser comparison test: Internet Explorer vs. Firefox, Opera, Safari and Chrome". PC Games Hardware. Computec Media AG. Retrieved 2010-06-28.
- "Lifehacker Speed Tests: Safari 4, Chrome 2". Lifehacker. Retrieved 2010-06-28.
- "Mozilla asks, 'Are we fast yet?'". Wired. Retrieved 18 January 2019.
- Safari 5 Released
- Stachowiak, Maciej (November 9, 2008). "Companies and Organizations that have contributed to WebKit". WebKit Wiki. Retrieved April 13, 2019.
- Belfiore, Joe (2018-12-06), Microsoft Edge: Making the web better through more open source collaboration, Microsoft
- "Microsoft Edge and Chromium Open Source: Our Intent". Microsoft Edge Team. 6 December 2018. Retrieved 8 December 2018.