title: How should I support and continue development on a forked application?
body: <p>We have a large application that runs at roughly 5 locations. None of these locations are running the same version of the application. This makes patching and updating very complicated.</p>
  
  <p>Try to follow this example: We'll call the application I'm talking about "application A". Now we want to roll out an application B to one of these locations and it must implement application A. We'll have to modify A to accept B's requirements. However, our development version of A (the version that eventually each location will have) must have support for B as well. This means we have to rollback to the state of the software running on the site requiring B as well as make these changes to our development version of A. This also means that the 4 other locations are implementing a version of A without B support.</p>
  
  <p>So one can see where it gets frustrating to control the versioning. If we want to support sites 2-5 we can't use our development version of the source, we have to rollback to the specific version on that site. What's the best way to do this? Keep in mind we're using Visual Studio 2008 and Team Foundation Server.</p>