Ryan Paul had the opportunity to go to Facebook headquarters and get a behind the scenes look at how a typical Facebook update deployment works. Highlights include:

• Minor updates to Facebook happen every day. Major updates happen every week – usually on a Tuesday. This rapid development schedule is part of the reason for Facebook’s agility and success.
• The frequent updates make testing difficult. There are three main stages of testing. First after the developer submits the code, the update is rolled out to all Facebook employees. After that the pages of a small number of randomly selected public users are updated. If there are no problems then the update finally goes out to everybody’s page in a process that takes about half an hour. There is rarely any downtime.
• During the update rollouts every developer is expected to be on hand in case of any problems. Developers are responsible for the code they submit and if their code breaks down they have to fix it. Those that do badly get a thumbs down and can accumulate negative karma.
• Facebook monitors several sources of data for evidence of problems with updates. These include Twitter streams and how favourably people are tweeting about Facebook.
• There is a well-stocked bar where the release engineering team works. The team leader sits within arm’s reach of the bar.
• After a successful update the developers celebrate by taking a few shots.

To read more about Facebook’s plans for the future, the one man in the world who has access to a dislike button, how disgraced developers can increase their karma through alcohol, and the 1.5 gigabyte binary executable file that creates the magic, click here.

Source: ArsTechnica