Software To Automate PHP Script Updates?


we are making a php script for shopping carts and are looking for a program or software that will help us in automating updates to the script when we need to patch client sites. We have many customers that will be using it. I searched Google and could not find any. Does anyone know of any?

Do you control the hosting or is this a lot of different hosts? And are you doing all of the deployments or is this something the client could download and install?