We are looking for a passionate Backend Software Engineer to join the Fulfillment Optimization team. This team builds the platforms that determine how customer orders are fulfilled, optimizing for Wayfair profitability and customer delight. A big part of our work revolves around enhancing and scaling customer-facing platforms that provide fulfillment information on our websites, starting at the top of the customer funnel on the search pages all the way through orders being delivered. Throughout this customer journey, we are responsible for maintaining an accurate representation of our dynamic supply chain, determining how different products will fit into boxes, predicting how these boxes will flow through warehouses and trucks, and ultimately surfacing the information our customers need to inform their decision and the details our suppliers and carriers require to successfully execute on the promises made to our customers. We do all of this in milliseconds, thousands of times per second.