After a short "sanity check" interview with their HR department, I had a fairly easy technical screen focusing on my core C++ skills and basic design. This was followed by a second phone screen with a Senior Engineer that delved much deeper and was more challenging.

This interview covered knowledge of programming practices, code, design patterns, and more.

Passing this led to a full day in-person interview. This consisted of a series of talks, mostly with people in the same department, covering relevant skills (with many whiteboard problems). There was also a significant set of interviews with people from other departments.

The culture at Riot was obviously that of a young company, with many jokes, but clearly, everyone got along quite well. The technical interview was quite challenging, going into great depth on low-level knowledge as well as big-picture design. It was easily the most challenging technical interview I've had in person, but it never felt like a barrage of trivia questions. When I didn't know an answer, I was encouraged to take a stab at figuring out how I might solve it.

How can you create a 'final' class in C++ that is enforced by the compiler?