HTTP requests, heavy/unminified resources, and UI thread blocking should be on the mind of every front-end developer. These are just a few issues that can cause serious bottlenecks in page load times. Having a faster load time equals better search engine rankings, higher conversion rates, and an overall reduction in bandwidth costs. How do we measure all the aforementioned performance killers? How can we bring these measurements into our automated build process to ensure that our site is getting better, and not worse?

PhantomJS, a headless WebKit with JavaScript API, gives us the ability to create lightweight performance measurement tools with JavaScript (and so much more). In this talk we’ll review how PhantomJS has influenced some of the web’s top ranking sites and how it can be put into any automated build to produce reporting on performance. We’ll look at how other open source projects such as WebPageTest.org measure up to this approach and see when one might be better over the other.