Working on the Facebook News Feed design means making decision that affect literally billions of people. Still, the classic Question, Solve, Validate process works, at even that scale. “Small changes, like a few extra pixels of padding or the tint of a button, can have large and unexpected repercussions.” So how do they do it? By communicating regularly with users and gaining valuable feedback. Areas that were identified as needing improvement were improving readability on the news feed, making comments more conversational and engaging, and making navigation between news feed stories easier.