Always Ship Trunk: Managing Change In Complex Websites

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Version control systems are essential for managing any slightly complex software project, but few teams have given much thought about how to get the most out of their repository.

The most common best practices for source control are based on the needs of shrink wrap or open source software. Running a website is different, and needs different approaches to tracking modifications.

This session will take an in-depth look at the idea of shipping trunk and branching in code. We’ve found that this technique reduces the risks associated with change, allowing you to:

  • Deploy frequently, facilitating rapid product iteration
  • Avoid large merges and the associated integration testing
  • Easily perform A/B testing of functionality
  • Run QA and beta testing on production hardware
  • Launch big features without worrying about your infrastructure
  • Provide all the switches your operations team needs to manage the deployed system

We’ll discuss how (and why) you’d want to do all this, and cover some of the downsides of this technique.

The ideas discussed will be useful for both developers and operations, and will work with any revision control system from CVS to Git.

Paul Hammond


Paul Hammond is a web developer, product manager and father. He has been building websites for as long as he can remember, and now leads a team of hard-working supernerds at Flickr. Before then he was part of the Yahoo Brickhouse team, and previously led technical project management at BBC Radio and Music interactive.

Paul regularly speaks on subjects from Javascript and APIs to the future of broadcasting, at events including South By Southwest, Web 2.0 expo and Web Directions North. He currently lives in San Francisco, and keeps an irregularly updated technical weblog at

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Picture of Ernest Mueller
Ernest Mueller
06/24/2010 10:19am PDT

Interesting stuff. Notes from this session here:

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