Participated in three of four one-to-one interviews:

1. Screening session with the hiring manager. This is a general 'get to know you' session and is also a great opportunity to get to understand the company a bit more and what you could potentially be working on. This interview lasted roughly 45 minutes.
2. Take-home coding exercise and follow-up review. The coding exercise takes roughly 2 hours, with the follow-up interview being one hour.
3. Systems architecture interview (question below). This interview lasted roughly 1 hour.

I thought all the interviews went well, but didn't get an offer. The interactions with the company were all conducted professionally. From an outsider's perspective, I had good impressions of the company.

Presented with a small design for an image conversion service. A few different scenarios are presented with increasingly complex requirements. The aim of the exercise is to discuss how to architect improvements to said system that are scalable, available and production-ready.