Facebook details the AI technology behind Instagram Explore

According to Facebook, over half of Instagram's roughly 1 billion users visit Instagram Explore to discover videos, photos, livestreams, and Stories each month. Predictably, building the underlying recommendation engine -- which curates the billions of pieces of content uploaded to Instagram -- posed an engineering challenge, not least because it works in real time. In a blog post published this morning, Facebook for the first time peeled back the curtains on Explore's inner workings. Its three-part ranking funnel, which the company says was architected with a custom query language and modeling techniques, extracts 65 billion features and makes 90 million model predictions every second. Before the team behind Explore embarked on building a content recommendation system, they developed tools to conduct large-scale experiments and obtain strong signals on the breadth of users' interests.