Uma implementação Python pura do [Cassowary constraint-solving ] (http://constraints.cs.washington.edu/cassowary/). O Cassowary é o algoritmo que forma o núcleo do mecanismo de layout visual do OS X e do iOS. do OS X e do iOS.
This project is no longer in use. It was originally developed for use in Toga; however, Toga now uses CSS-based layout, implemented in Colosseum.