Squirrel is an experimental design-pattern search engine. It uses community-question answering techniques to try and provide a list of design patterns that could help address a particular design problem.

Squirrel is very much in its infancy at the moment and still under heavy development. It is an experimental prototype, no more, no less.

Squirrel has originally been written by Panos Katseas as part of his MSc thesis at King's College London. It has then been extended and revised by Steffen Zschaler and is currently being extended and improved by other MSc students.