GUIDEWIRE STUDIO
Guidewire Studio is an IDE for Guidewire's enterprise software platform. It includes support for editing Gosu, Guidewire's programming language, a quasi-WYSIWYG page configuration editor for Guidewire's UI framework, and configuration editors for Guidewire's rules engine, workflow engine, and more.
I have been the lead developer on Studio for two years, and am currently leading an effort to convert it from a standalone Swing application to a set of Eclipse plugins. Prior to that, I led the design and development of Studio's UI configuration editor, which facilitates UI authoring by providing drag-and-drop, rapid error feedback, and code completion facilities.