Methods, computer program products, and systems are presented. The method computer program products, and systems can include, for instance: examining programming data defining a first user interactive user interfacing application for interactive engagement with an end user; examining programming data defining a second user interactive user interfacing application for interactive engagement with a user; identifying one or more difference between the second user interactive user interfacing application and the first user interactive user interfacing application using result data resulting from the examining programming data defining a first user interactive user interfacing application and resulting data resulting from the examining programming data defining a second user interactive user interfacing application; and generating update data for updating the second user interactive user interfacing application in dependence on the one or more difference between the second user interactive user interfacing application and the first user interactive user interfacing application.