Amazon Software Development Engineer, II interview questions

A recruiter reached out to me on LinkedIn and asked if I was available to interview. I scheduled a 30 minute initial screening with them. It included the basic, tell me about yourself question, the nature of work done, how big the team is that I am a part of and how many people have I mentored or managed directly followed by what is the number of customers serviced by the products I have worked on developing. They shared study material after that which included a Data Structures Big O time notation sheet, some brochures about the company and team and links to Leetcode, Hackerrank and Cracking The Coding Interview. They sent me an online assessment in a few weeks. I asked them to send it after a month so that I could prepare prior to taking the assessment. I prepared by solving as many Amazon tagged Leetcode problems as possible. There were 2 questions (both were LC medium) sliding window problems. I solved one and all the test cases passed. I was close to the output for the second one but some test cases did not pass. Both my solutions were optimized and ran in O(n) time. They progressed me to the onsite rounds. There were 4 rounds, 2 System Design, 1 Object Oriented Design and 1 coding round. I was surprised by the number of design rounds and had unfortunately not prepared some of the topics they asked and not prepared for OOD rounds either. They also asked several Leadership Principle (LP) questions, they expected a concise answer following the STAR approach and asked not to mention "we" but talk about what "I" did specifically. They had 2 to 3 follow-up questions on every LP answer. The onsite lasted all day, was virtual and was exhausting. I experienced poor connectivity issues on my interviewer's end in 1 of the interviews so that one ran longer than the others into the lunch break. The whiteboarding tool they suggested also did not work well with Amazon Chime, upon screen sharing, the tool did not work as it did without screen sharing. I would recommend testing the whiteboarding tools recommended by them thoroughly before the onsite rounds. Some don't work as expected.

Everything started with a recruiter's message on LinkedIn. The overall process took 3 months. I was looking for an SDE I position but a recruiter approached for an SDE II position. I would say 4 events took place after that. Event 1: Online Assessment - 90 minutes hackerrank test. There were two coding questions and two subjective (analysis of the solution to the code written for the coding questions). Event 2: A phone interview. One behavioral question and 1 coding question from Tree. Followup on coding question required space optimization. Event 3: Final virtual onsite interview. Four rounds of interview. The length of each round was an hour. There was a lunch break after the second round. Round 1: The interviewer was a Principal Engineer. The first five minutes were the introduction of each other. The next 15 minutes were for behavioral questions based on Amazon Leadership Principles. Pretty much followup on my answer. Next 30 minutes was for coding question related to the hash table and string manipulation. I found it straight forward and solved it. The interviewer asked a few questions regarding optimization and time complexity. The last 10 minutes were given for me to ask questions. The interviewer was very welcoming and made me feel very comfortable. Round 2: There were two interviewers in this round. One was Front End Engineer II leading the interview and the other was Engineering Manager. The first five minutes were the introduction of each other. The next 15 minutes were for behavioral questions based on two different Amazon Leadership Principles. Pretty much followup on my answer. The next 35 minutes were for the system design question. I started with assumptions of different microservices on the backend. The Engineering Manager asked several questions on the database schema and reasons for using the specific technology. Frontend Engineer II wanted to move forward with API design as we were already running out of time. The last 5 minutes were given for me to ask questions. The overall experience was very comfortable. Round 3: The interviewer was a Software Development Engineer II. The interviewer gave an introduction and moved to behavioral questions. Had one follow-up on my answer. 15 minutes was passed by then. Next 40 minutes was for coding question related to logic and maintainability. I found it straight forward and solved it. The follow-up question was pretty tough and I could not solve it even though I had already thought of the process till we just had 8 mins left. The interviewer then asked for my thought process to solve the problem. I explained it and he seemed to be convinced with my answer. I was then given the last five minutes to ask any question. Round 4: This round was with Software Development Engineer II and was the best experience among all four. The first 5 minutes were again for the introduction. Then 15 minutes for the behavioral questions. I had never been in the situation that the interviewer wanted me to explain so I said, "I have not been in that situation so if you could ask something else". I had heard from Amazon engineers that it's not a red flag if you say so. Then Next 30 minutes was for the coding question. The question was of a greedy approach and also required writing a custom class. I solved it in 15 minutes. I was continuously pitching my idea while writing the code so the interviewer said "you are right, but maybe you want to go through and check for some typos". I went through and saw I was comparing the wrong attribute of the class and fixed it. I was then asked a follow-up question which I solved in the next 10 minutes. Then the interviewer said "well we still have some time so let me ask you something." Then asked one more follow-up question and told to explain the thought process. I explained it and she said "awesome". That word made me feel very confident. Then I was allowed to ask any questions I had. Event 4: I got a call from the recruiter. The recruiter said that the team felt I am not ready for the SDE II position but was able to raise the bar for SDE I position and decided to offer an SDE I position. I was happy and said yes to the offer. Then there was a twist. The team I had an interview with did not have SDE I position available so the recruiter had to find a team for me and asked my preferred location. I chose Seattle. The recruiter came up with two teams next week but that did not work out for me. Then it took 3 weeks for the recruiter to come up with one more team. The call with the hiring manager went very well. Later that evening I heard from my recruiter that the team is offering me the position. I celebrated. Hard work paid off. The next day I signed the offer.