Development and Deployment at Facebook
Dror G. Feitelson, Eitan Frachtenberg, Kent L. Beck · IEEE Internet Computing · 2013
Internet companies such as Facebook operate in a "perpetual development" mindset. This means that the website continues to undergo development with no predefined final objective, and that new developments are deployed so that users can enjoy them as soon as they're ready. To support this, Facebook uses both technical approaches such as peer review and extensive automated testing, and a culture of personal responsibility.