Software product line engineering provides a systematic approach for the reuse of software assets in the production of similar software systems. For such it employs different variability modeling and realization approaches in the development of common assets that are extended and configured with different features. The result is usually generalized and complex implementations that may hide important dependencies and design decisions. Therefore, whenever software engineers need to extend the software product line assets, there may be dependencies in the code that, if not made explicit and adequately managed, can lead to feature interference. Feature interference happens when a combined set of features that extend a shared piece of code fail to behave as expected. Our experience in the development of YANCEES, a highly extensible and configurable publish/subscribe infrastructure product line, shows that the main sources of feature interference in this domain are the inadequate documentation and management of software dependencies. In this paper, we discuss those issues in detail, presenting the strategies adopted to manage them. Our approach employs a contextual plug-in framework that, through the explicit annotation and management of dependencies in the software product line assets, better supports software engineers in their extension and configuration.