Counsyl Software Engineer Interview Questions
& Process

A recruiter hit me up, and since I was moving and they used Python and seemed like a useful company, I bit. We did some initial phone/skype interviews, but I barely remember them - nothing major, just checking if I was totally unqualified. I'm in web ops, which Counsyl didn't have then (devs ran stuff), so they didn't know how to interview me and just interviewed me as a developer. That's fine, I can do it, but it's not what I'm into or what I'd be doing, so it wouldn't be super useful. The in-person interviews had five developers (randomly picked, I guess) spend an hour with me each, then I talked to one of the higher-ups (CTO-ish?). It was annoying because none of them prepped - they read my resume right then and asked stuff answerable by looking at my Github. If I work hard to make my code visible, the least they could do is not waste my time flying me up to rehash it; we couldn't get to the more interesting interview stuff. Also, every single one had me code a memoization problem. Some places like recursion, some like pointers, but Counsyl is all about memoization. Wish they'd coordinated so I didn't do the same thing five times. The only different one was talking to the bigwig. He asked me to architect Imgur and what happens when a user uploads an image. I figured the frontend was trivial (just a form), so I glossed over it, but he kept bringing me back - clearly wanting something else, but I had no clue what. Maybe 'cause I'm backend, but I think all the interesting stuff on a site like that is server-side. I'm practical; my uni put us in labs day one and required internships, and I worked part-time in the field through college. Counsyl was clearly full of more academic people; in the few minutes I asked interviewers about themselves (annoyed they didn't read my open-source code meant I only had time for one or two questions each), I found none had industry experience, all were deep into academic research and saw Counsyl as just a better-paying research job. My take: smart people, but they desperately need practical engineering sense - someone who knows complex systems fail, so plan for it, and humans mess up all the time (plan for that too). One interviewer, asked about the hardest part of working at Counsyl, said users, 'cause he'd never dealt with people using his stuff in unexpected ways before! They said they rejected me 'cause they wanted someone with more experience to start operations. I don't blame them, though they underestimated my experience (a year out of school, I had five years, including leading an Alexa global top-5k site). They have a good base, and if they hire fewer PhDs, they'll succeed.

I was first given a programming test that I had ample time to complete. After submitting my solution, I was informed by the reviewing engineers that my performance was excellent. I then provided my availability for an interview. However, despite my follow-up emails, there was no further communication. It would have been considerate to at least provide a brief response if I was no longer being considered, rather than being ghosted. Up to that point, the recruiter had been very responsive and pleasant.

You get a week to complete a coding test with two problems. One is way harder than the other, and your code needs to be efficient enough (BigO) to pass all their test cases. Then, there's a Skype interview where you'll do some simple Python coding questions with a CoderPad while the interviewer watches. Finally, you'll have an onsite interview where you meet 5 engineers and do a whiteboard coding problem with each of them.