The process took 3 weeks. I interviewed at Candlewick Press (Somerville, MA) in Aug 2016
Interview
Received email asking for an in-person interview after 2 or 3 weeks after my application. There were two people interviewing. One from HR and one from the Art Department.
Pleasant, met first with HR and then with the team lead of the department I was a candidate for. Both friendly, and it helps to be knowledgeable about the company, including authors and illustrators of some of their more popular books/series.