Engineering resilient distributed systems remains extremely challenging, particularly in mapping from collective specifications to individual device behavior. Aggregate programming aims to address this problem using a computational field abstraction to provide inherent guarantees of resilience, scalability, and safe composition. These capabilities are provided, however, by an expressive but terse set of operators too low-level for pragmatic use in complex systems development. We thus present an API to raise the level of abstraction, thereby providing an accessible and user-friendly interface for construction of complex resilient distributed systems. In particular, we capture and organize a large, heterogeneous collection of algorithms and use patterns into a unified framework, including methods for common tasks such as leader election, distance and state estimation, and gossip-based information dissemination. We demonstrate how the expressiveness of this library reduces the abstraction gap required to engineer scenarios of large-scale pervasive computing, while introducing the novel multiInstance pattern enabling an unanticipated composition of computational fields.