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News From CloudFlare Labs: Javascript Preloader Research

2011-05-03

1 min read

Some of the techniques that CloudFlare uses to make sites faster and safer have generally been around and used by the Internet Giants for some time. In other places, CloudFlare is breaking new ground in offering state-of-the-art technologies to increase performance and security. We roll these technologies out to our users either as options or enhancements to our core service. Where we can, we also offer our insights back to the community.

Take, for example, our work in Web Content Optimization (WCO). This goes beyond your traditional caching CDN to actually optimize the way your site renders on a particular browser or device. Jason and Chris have been working on a number of performance improvements that we can then deploy to CloudFlare. One tricky challenge is how to reliably "preload" Javascript without it actually executing on the page. While some of the established techniques work in controlled environments, when you try and deploy them on the wide range of websites behind CloudFlare, and the wide variety of devices that access those websites, you see they fail in some interesting ways.

Jason just published CloudFlare's latest findings on preloading Javascript without execution:http://static.jtwb.dotcloud.com/research/preloaders.html

The good news? We have an incredible solution that is innovative and going to completely revolutionize web performance, especially on mobile devices and we're going to be turning it on to all our users (even those of you on the free service) soon. Stay tuned!

Speed & ReliabilityJavaScript

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Matthew Prince|@eastdakota
Cloudflare|@cloudflare

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