Detailed discussion of tips, tools and strategies for maintaining internal software forks with a particular emphasis on FreeBSD and its use in EMC's Isilon Storage Division. Occasionally you need to fork a project. You probably still want to track the upstream version but you've got local modifications you need to maintain. The EMC Isilon Storage Division does this with FreeBSD in a big way. This presentation will go through what happens when you don't keep up to date and how you can get back up to date in a way that can still mesh with your release process. It'll also go through tools you can use to help the process along and keep your project managers happy and strategies for making sure you don't get behind again.