I recently finished a couple of weeks of interviews for a mobile application developer position at Capital One’s flagship “Cafe” office in downtown San Francisco. I figured it would be good to recap my experiences for the next person who comes down the interview pipeline.

In addition to being another “big bank” (or big bank wannabe), one of Capital One’s initiatives is to try to come up with products and services that drive customer “engagement” – that is to say, active usage and churning within the customer’s various Capital One accounts. There are two mobile apps actively in development, apparently related to “shopping” and “travel.” The first app has been in development for at least two years, and the second is a much newer product. Neither of these apps is on the app store, and I wasn’t given the opportunity to see a demo of them. There’s also some third consumer-facing mobile app on a whiteboard somewhere. So this is why Capital One is actively trying to hire mobile developers.

In the San Francisco office, there are at least two or three product managers plus a PM boss, and at least two or three mobile developers per platform and an engineering boss.

I didn’t get a close look at the office environment, but the office area, which takes up the third and fourth floors of the building, is not nearly as big as the much more impressive ground and second floors that the general public is welcome to visit. The interview room was very small, with a modern-looking steel barn door and walls that doubled as whiteboards. There’s a fully stocked fridge next to the interview room, with bottled water and soft drinks inside.

The interview process started with phone conversations with two PMs, who were exceedingly friendly. I also got to speak with the engineering boss on the phone, who certainly seemed nice enough. After three or four phone interviews, I was invited in to do half-hour interviews with three different people:

• One of the PMs I had talked to on the phone.
• The PM boss, who kept a strange, poker-player, unreadable face the entire time I spoke with him. He seemed impossible to get a sense of whether or not he was skeptical of me, or if he was just being awkwardly friendly.
• The last person was a developer, and it’s there I ran into trouble.

Regarding the two mobile developers I spoke with, I wasn’t very impressed with these potential direct co-engineers.

The first one I spoke with on the phone asked me a number of technical questions that I felt good about the answers to. As a homework assignment, he gave me two different programming problems to solve, including one full-blown, compiling, and functional mobile app – within 30 minutes in total for both. I’m a little more experienced than the average candidate, so I did deliver both solutions within that 30-minute deadline (with a couple of algorithm adjustments that I sent in a follow-up email a few minutes after the deadline had passed). I’ve done plenty of small programming projects and homework assignments for job interviews before, but this was the first time I’ve been told to code up multiple answers with such a short deadline. I think this would be a somewhat stressful challenge for the average developer.

Here are the two problems he had me code up:

1. Write an algorithm that reverses a linked list (this is a standard algorithm question any engineer of any experience level should expect).
2. Write an app that displays one of multiple pictures and add swipe gestures to the picture, swapping pictures when one is swiped off-screen.

During the in-person interview visit, I got to speak with the second mobile developer. He blasted me with a few deep programming language questions, and to my dismay, didn’t seem particularly pleased with any answers I was giving back to him. He had me design out a 2-3 screen shopping app, describing the architecture and the classes I’d use to assemble the thing. This is where I pulled out the marker to do some drawing on the whiteboard. He still didn’t seem impressed with my descriptions of things. It may have been that he wasn’t explaining his question well, or more likely, what he was really looking for were specific answers he wanted to hear. In retrospect, I walked out of there thinking he may have been purposely trying to agitate me to see how I’d work well under pressure. So, if I had to guess why I flunked the interview process, this guy (who was not an employee but instead a contractor) would be the veto on me going forward. Definitely not a friendly or welcoming culture fit.

Hopefully, my experience flunking the Capital One interview will help you prepare to pass your interviewing day. If you find any of the information in my interview review helpful, please let me know by voting "Yes" on the "Helpful?" question below. This helps to motivate me to be as detailed as possible.

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