In regular websites, it is common to send multiple events to track user clicks. Single Page Applications change the way you look at metrics. This is a talk about a simple pattern we created at Globo.com to manage a metrics layer for http://globoplay.globo.com. The talk will cover how to track user flow using Google Analytics and other services. We solved the challenge of tying metrics and components, keeping information across pages and having global data. Also some React, React Router and React Side Effects concepts like context, higher order components, history state will be covered.