Coding interview asked you to complete object oriented question based on question provided, then you are required to improve you code quality up to thread safety/concurrent one.

General tech questions asked mainly focusing on microservice, java internals and concepts about monitoring system. But you need to figure out what type of question the interviewer wants you to answer based on the situation/incidents he described.

System design questions, that is the easiest part as far as I have met during the interview process. You could pass this round if you are familiar with System Design Interview – An Insider's Guide: Volume 2 by Alex Xu.

Culture fit interview experience is quite different from where I interviewed with Amazon. The director level of manager asked my personal background first then asked questions about agile methodology, incident handling experience, innovative break, and my taste of working with people. You answer must align with your work experience which you would start at the very beginning. This is really a tough behavioral interview I've meet.