Pyre is a problem solving environment and integration platform for massively parallel computational engines. Written in Python, Pyre is an extensible, object-oriented framework for specifying and staging complex, multi-physics simulations. Pyre, which has the ability to utilize pieces of code written in other languages, provides a level of transparency that allows scientists to focus on their research rather than being distracted by computational details. However, while Pyre will enable the average user, it was also designed not to hinder expert users, offering powerful, flexible development features.