The longest and most in depth interview process I have personally ever experienced, despite the fact that it was all remote due to the COVID-19 pandemic. I was contacted by an Ab Initio HR representative on Linkedin (who was really helpful, professional, and very kind throughout the process), and from that point to receiving the offer took 2 months, a brief take home exercise, and 13 interviews, all of which were scheduled to be at least an hour long. Due to the lockdown, all of these interviews were conducted remotely which meant that the process was expedited enormously - the second half of the interview process would normally take place in Massachusetts but obviously this was impossible. I had also informed the company of another offer I had received, so I think I was fast tracked as much as possible, which was very thoughtful of them. The process began with a phone screen, which was a mixture of some information about the company (almost none is available online) and a few technical questions mainly related to elements on my CV. Then I was sent a take home exercise to complete in Python, which was straightforward and took me less than an hour. This was followed by a Zoom interview where the in-depth nature of the interview process and more details about the role were given. At this point I was asked to sign an NDA, which I did, and therefore I won't go into too much detail about the rest of the process, except to say that it involved 2 days of 3 interviews each, the first with UK based staff and the second with staff in Massachusetts. A few went into detail about their software, and most of which involved some algorithmic discussion. Overall, while there were a lot of interviews, they were generally very enjoyable and all the Ab Initio staff were great to talk to. My advice would be to have at least one very technically challenging piece of work to discuss, and to be prepared to have that discussion quite a few times. Brushing up on Data Structures and Algorithms would not hurt either: they are looking for people who are confident communicating both technically and non technically.