I worked on CI @ FB for multiple years before leaving last year.<p>>what does Meta’s CI infrastructure look like?<p>At it's core is a broken mess of Hack classes that I consider to be some of the worst code at the company. This, of course, varies depending on the platform. The developer experience for web (hack/js) was pretty good, but for mobile it was absolutely dreadful and wasn't getting better when I left. Depending on what code you were touching it could take hours to get signal.