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      Senior Frontend Engineer Interview

      8 Apr 2026
      Anonymous interview candidate
      No offer
      Positive experience

      Other Senior Frontend Engineer interview reviews for Customer.io

      Senior Frontend Engineer Interview

      13 Apr 2021
      Anonymous interview candidate
      New York, NY
      No offer
      Easy interview

      Application

      I applied online. I interviewed at Customer.io in Apr 2026

      Interview

      I applied through website and the whole process took me around 2.5 weeks and 2 interview rounds. 1. The HR interview was very smooth and pleasant, and I was moved to the next stage. 2. The interview with the Director of Engineering was more focused on my professional experience - the challenges I faced at previous companies, mistakes I made along the way and how I handled them, my approach to using AI, and similar topics. Unfortunately, despite the fact that it went relatively well (or so it seemed to me 😁 ), I was informed that they are moving forward with other candidates. But based on my research, I believe this is a great place to work, with a wonderful team and interesting challenges, especially for Frontend engineers.
      Positive experience
      Easy interview

      Application

      I applied online. The process took 3 weeks. I interviewed at Customer.io (New York, NY) in Feb 2021

      Interview

      About 4-5 interviews in total. The first is a chat with their HR lead, the second with the dev team lead, the third with the lead front end engineer, the fourth is a couple of front-end engineers to review your work. Supposedly the last one is an interview with the CEO.

      Interview questions [1]

      Question 1

      How would you crunch a lot of numbers in a browser without locking up the UI?
      Answer question
      1