The HR person contacted me a couple of weeks after I had applied online. An interview was arranged with four people through video chat. The first few questions were about 'what have you worked on so far?', 'Tell me a day in your current job' and other behavioral ones. Then, a few were on basic OOP concepts, a small programming problem on data structures and several testing related concepts such as test plan, test metrics, test design, test automation, and some fundamentals of computer science such as stack vs. heap and memory management. About 3 weeks later, 1:1 interview with 5 people was set up again in Cambridge MA. Questions were similar but heavily behavioral as they wanted to see how I am to work with. The technical ones were mostly knowledge based and on Windows OS such as event viewer. I was also questioned on knowledge of testing certain web service APIs. In between the whole process, there was a lot of disorder from HR and the interview panel on availability and setting up the interviews.

Started with a phone screen, met with one of the founders who was very nice, competent and informative; then acting manager who didn't seem to know a whole lot yet about what the direction of the group was and what type of candidate they were looking for; finished with an interview with an automation engineer who did a lot of technical grilling.