TikTok Frontend Software Engineer interview questions

Went through several rounds of interview with the HR and team leads. Questions were reasonable, mainly focusing on system design and past experiences questions. The interview process was quite drawn out especially after the final interview. Was told weeks later that I am not good enough compared to other candidates for the role. Bummed to have waited almost a month after the final interview to learn that the position I was interviewing for has been filled.

They asked me about my previous work experience and go deep about the project i worked on. During the process he asked me about the design of the architecture and possible scenarios that could happen. How to improve the performance. Then it comes with a hard coding question.