Long-running applications such as network services require continuous uptime but also frequent changes to the software. To avoid downtime for software maintenance, applications must be updated at run-time. We describe a system based on the ideas of aspect-oriented programming (AOP) to manage such updates. Join points as defined by AOP establish locations for code modification in a program. We use these join points to guide software updates. Updating a system is a two-step process: the original (old) and new (updated) versions of a software system are compared and a list of update actions and pointcuts is constructed. We present a case-study to evaluate the applicability of this approach.