Static architectural conformance checking can be used to find architectural violations, cases where the implementation does not adhere to the architecture, and prevent architectural erosion. We implement a software service for automated conformance checking and investigate the effect this has on the number of architectural violations in software projects. The service is implemented using our heuristic-based approach to static architecture conformance checking of the Model-View-Controller pattern. The service is integrated in the source code management system of each project, so a report is generated every time the source code is modified. The service was evaluated in a field experiment that consisted of eight student projects. We found that the four projects that used the service produced significantly fewer violations compared to those that did not.