Hermes-F is a framework that enables the development of applications that perform information retrieval(IR) tasks. Its central component is an extensible server that provides access to a variety of IR models, query transformations and digital collections. We have successfully instantiated our proposed framework by implementing a fully operational IR server that is accessed from various digital library applications. We describe the Hermes-F environment and focus on our experiences with this instance of the application framework. We report on various tests, as well as on our results of using and extending the available IR models for diverse collections.