I applied online. I interviewed at Klaviyo in Oct 2020
Interview
First round is a phone screen with a developer, which was almost entirely behavioral. He asked me some questions related to my past experience, but nothing that required much prep. I heard back early next day, though it took almost a month to schedule the next round, which was technical. They present you with semi-working code revolving around REST APIs, Python and SQL. Your job is to optimize it (there are some errors as well). Honestly I wasn't too comfortable working with flask, etc, so I didn't do great. The interviews (2 of them) were understanding. and will help you if you ask for clarifying questions. Took another week until they got back to me.
All in all, I truly believe this is a great company to work for, especially since they are headed for IPO soon. clients seem to love the product, but the hiring process was long, drawn out. Had they gotten back to me earlier, I would've explored other opportunities—but this is just the job game. Good luck everybody
Interview questions [1]
Question 1
They present you with semi-working code revolving around REST APIs, Python and SQL. Your job is to optimize it (there are some errors as well).
HR screening. Asked me some questions about software basics and sent me a code signal link. Asked about how I utilized AI in day to day work and how much design work versus coding task
ICF Codesignal, recruiter screen, and then final interview. Codesignal was easy as long as you prepped for it, there are many examples of ICFs online. Recruiter screen was normal. Final interview was not DSA related. Mostly related to the real experience of being a swe.
Application
I applied online. I interviewed at Klaviyo (London, England) in Mar 2026
Interview
The interview process was generally well structured. I had an initial 30-minute recruiter call, followed by an assessment task and a hiring manager interview. The final stage consisted of three separate one-hour interviews covering different skill areas, with two interviewers in each session. One focused on frontend skills, while the others leaned more toward backend and broader technical competencies. Overall, the experience was positive, though having a three-hour final stage in a single day felt quite intensive.
Interview questions [1]
Question 1
Do a code review and fix what might be wrong or how you would fix it.