We have distributed crawler written in go configurable with xpath and javascript for advanced crawling using javascriptcore-go[1] and also our knowledge engine serves various form of formatted information card scripted in javascript.

Duckduckgo goodies[2] also a good example of what we've been doing.

1) https://bitbucket.org/rj/javascriptcore-go

2) https://duckduckgo.com/goodies