Building an eCommerce system is not easy, and building a platform is even harder. When it comes to data in eCommerce, there is nothing definite, no real structure you could stick to, and no final requirements. Something as obvious as the "item you add to cart" could be overly complicated when it comes to data. In this talk I will cover how we used MongoDB in a real world ecommerce system at OpenSky - an ecommerce startup in NYC - and how that changed the way we think about data and improved overall system design and performance