Nowadays, users expect your app to be not only fast and reliable but also smart. As a consequence, more and more teams are becoming data-intensive — relying on data to build their solutions. And it’s a common belief that putting models into production is one of the biggest bottlenecks in a journey of becoming more data-driven. While true, this step is only the beginning of the journey. I believe that a much broader transformation is required in how we think about product development lifecycle as well as communication flows between business, engineering, and data. In this talk, I’ll show how we are building data-grounded solutions in the domain of search and recommendations and instilling an experimental culture in one of the biggest online marketplaces.