Current Employment
Position: iOS Engineer at Mercari Inc.
Location: Tokyo, Japan
Date: June 21, 2020

Background
I have an experience of 6.5 years as an iOS Engineer. I worked for a company called Directi in India for 5 years and currently working in Mercari Inc. from past 1.5 years.

Initial communication
I was contacted by a recruiter on e-mail in Jan 2020. At that time I was not ready for interviews, so I told the HR that I will get back to them after a few months and so in May 2020, I contacted HR again.

Phone Screening (45 mins) - May 2020
Binary string addition question (LC easy) - solved it without any issues.
Average of last k integers at any point from a stream of integers question - solved it but not the best solution.

Overall impression: the interviewer was extremely nice. I got the impression he was interested in my success. The feedback was that I could have done better in the second question but overall coding and logical reasoning skills are good.

Virtual onsite (4 x 45 mins) - June 2020

Coding Interview 1

• a string question (Not present on Leetcode) - solved it but interviewer had to correct me in one scenario and overall it took me first 25 minutes.
• a disconnected graph related question (LC medium) - Told the correct logic but only able to complete 90% of the code because the time got over.

Coding Interview 2

• In starting 5 minutes, interviewer asked me something related to iOS?
• a simple binary tree related question (LC easy) - solved it without any issues.
• iOS related coding question (Not present on Leetcode) - solved it without any issues.

Behavior Interview
No coding here. Typical behavioral questions:

• Conflicts related questions
• Feedback or criticism related questions
• Best or worst projects so far

I was able to answer each and every one of them very well from my past experience. Be honest about your past, don't sugar coat.

iOS System Design Interview

• Design the status feature in Instagram iOS app assuming that backend is available.

I was able to design the feature without much issues and covered almost every aspect of the iOS app development.

Overall Feedback
The whole interview process was quite good and all the interviewers were nice. Also, the recruiter is also very responsive and helpful throughout the process. Luckily, in just one day, I got an email from the recruiter that the overall feedback was positive. Overall coding skills looks good but a little bit of issue with the speed. iOS domain knowledge is quite good. Behavioral was the best out of all and design skills are also good and able to cover a lot of things. Recruiter passed the feedback for the final review, then after a week I got another email stating that they want to take one more iOS system design interview as they didn't get enough positive signal from the first iOS system design round.

Follow up iOS System Design Interview
In the first 5-10 minutes, interviewer asked me general iOS related questions.

• Design a flight booking iOS app assuming that backend is available.

I didn't feel very satisfied with my performance in this interview.

I am a bit scared as I saw many posts about E4 hiring freeze and I am not sure that I passed the level of E5 but hoping for the best.

It's been a week but still waiting for the final feedback from the recruiter. Will update it once I get the feedback.

Final thoughts
In the last six months, I did around 100 fb tagged questions and it helped me to improve my coding skills as well as to target those areas which facebook generally asks, although 50% of questions that I got in the interview were not from Leetcode.

[Update] It was very heartbreaking that I got rejected as the recruiter told me that my iOS system design skills didn't match E5 level and they are not hiring for E4