I applied through another source. The process took two weeks.

Zopa has a mature and sensible four-stage interview process which I will outline. I have seen this recruitment model slowly being adopted throughout the industry and welcome this. In my opinion, it is a much more realistic gauge of skill compared to painful and useless algorithmic white-boarding/challenges or the traditional rote-memory gotcha question approaches.

• Stage 1: Phone Screening – A normal phone screen. A full-time Zopa-employed internal recruiter will screen you and ask you questions about your background and interests. Then they will describe the role and Zopa. My recruiter here was exceptional and seemed down-to-earth and genuine, all of which makes it easy to decide if you want to proceed. Important note: this recruiter will stick with you throughout the rest of the process, which is nice.
• Stage 2: Deliverable – Build an application that takes a CSV file and loan amount as command-line arguments and then returns an output of the best loan rate based on the CSV file contents. Passing this assignment involves two things. Firstly, finding and implementing the correct compounding interest formula. Secondly, structuring your program in a modern and clean way. This is probably the area that needs to be improved, and they know it; I have seen a few other people's reviews/interviews come unstuck here. The assignment I received was relevant to the company and completely achievable, which is great, but had no marking criteria. The assignment brief makes it seem like they want this program in any language (even shell script) and will be marking it against edge cases and auto-marking. This couldn’t be further from the truth. The deliverable is marked on your application structure, programming technique, and test coverage/structure, which makes a lot more sense.
• Stage 3: Technical phone interview – An engineer will phone you for a chat and ask you a series of industry-relevant questions and give you a chance to ask some. This was handled well in my case. The questions were deep and varied but completely relevant to modern development; you must go in depth here and explain a series of concepts and design approaches. There were zero pointless memory-based language-specific questions or algorithmic gotchas. At the end, I felt challenged in a very good way.
• Bonus Stage: Friday Drinks – My recruiter invited me in for Friday drinks before my final stage to get a company culture feel. This was a good idea in my opinion. It gives you a chance to feel Zopa out, meet the crew, and in my case the CTO, and vice versa.
• Stage 4: Internal Interview and Pair Programming Exercise – This is a two-part interview process which takes around 1.5-2 hours. The first part was a meeting with a product manager and a senior/lead engineer. This part had more in-depth realistic development questions and scenarios coming from the engineer, with interesting management and process questions coming from the product manager. In my case, it was a great experience. The second part is a pair programming exercise in which I was tasked with adding a new feature to the technical exercise I completed in Stage 2. It was a good challenge with good questions throughout on a range of subjects coming from the engineer. I liked the challenge and appreciated how it used my existing project, and adding a feature is a realistic everyday encounter.

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