We didn't develop YCAdvice from scratch. In fact the motivation behind YCAdvice came from putting our core tech at
Polymer Search to work for something we've benefited from for a long time: YCombinator's powerful content for startups. Polymer Search's automation automatically converts any structured data to a ready to use and highly functional insights engine. Once we were able to generate YCAdvice's data and label it, rest was automatic.
Polymer Search's stack is mostly written in Javascript.