WebScarab : WebScarab is a framework for analysing applications that communicate using the HTTP and HTTPS protocols.
boomerang : boomerang is a piece of javascript that you add to your web pages, where it measures the performance of your website from your end user's point of vie...
Phantomas : PhantomJS-based web performance metrics collector and monitoring tool
tracing-framework : Rich tools for instrumenting, analyzing, and visualizing web apps.
The coach helps you find performance problems on your web page. Think of the coach as a modern version of YSlow. The coach will give advice of how your page can be faster.