An online coding interview then they waved the second phone interview and went to on site. At onsite, except for one interview which was about coding, the rest were basically asking the same question over and over again and they call it "System Design". Design a system like Netflix, design a system like Yahoo stocks, design a system that collects sensor data.
The interviewers were polite. One of them wanted to show how smart he is constantly bragging about how others steal his coding questions but the others were nice and modest. The coding problem was easy. The good part was the session with the hiring manager, during which I realized the company is treading on La La Land. Asked him how many clients they have and the answer was "we can't tell you now", which was very much telling. If you're a start-up that was founded 8 years ago, after so many rounds of funding, you should be yelling at the top of your lungs how many customers you have, not "can't tell you now but we have a 'healthy' number of clients".