Akamai Edge: Tracking the Performance of the Web with HTTP Archive

"We went from plain HTML and JS to using a package manager to automatically download 3rd party packages, a module bundler to create a single script file, a transpiler to use future JavaScript features, and a task runner to automate different parts of the build process."

"The paint timing API enables website creators to track and monitor the important metrics which affects perceived performance. Consider that 53% of users will abandon a site if it takes longer than 3 seconds to load (source). Being able to keep your paint times low is likely to keep your users happy and improve the perceived performance of your site."