The interview process was long, with a few gaps to pull extra details out of the recruiter, but many of the people I met with were really nice. The TLDR advice is: only pursue this place if you really, really are passionate about ecommerce and what Shoprunner specifically is doing.
The people I met with are committed to Shoprunner's goals and aren't shy about the fact that they're trying to take on heavy hitters like Amazon or that they don't expect Shoprunner to be around forever. They also were very focused on finding the absolute perfect candidate who would require little or no training, even if it meant delaying multiple projects that had strict deadlines. So if you get even a whiff of a hint that they aren't interested, back away and look elsewhere.
The process was straightforward - initial phone screen, then coffee with the recruiter, then later on if you get to the next step it was coffee with the manager who needed to hire. I had two of those manager meetings since there were two roles open at the time. As I wrote earlier, everyone was nice - but the social side of the interviews mattered way less than your answers, so if you try to do much or any wiggling to fit what they want, it's probably not worth your time.