Javascript A/B testing services are prohibitively expensive when you want to test for thousands of users. On the other hand, in-house solutions require implementations of data stores that can handle all these signals – a major project in its own right. In this presentation we’ll examine a Javascript-based solution to leverage Google Analytics and your Javascript skills to implement a simple and straightforward frontend A/B testing framework that can scale to testing across millions of users, for free!

UX doesn’t only come down to looks and speed. Error handling is quite as important and in order to get it right it has to be easy and straightforward. In this talk, we’ll find out how to achieve this in modern web apps.