Disorganised, dragged out, and poor communication.
It took 6 weeks between applying online and actually hearing back. From there, I had interviews with 3 different people. During the final interview stage, the zoom link I was given was broken, with no one to contact to solve the issue.
The interviews, which were relatively straight forward, made it seem like the people conducting the interviews hadn't done any research before the interview, and hadn't read my CV which felt very unprofessional.
After the last interview, I was told I would be informed within 2-3 working days if I had an offer or not.
3 weeks later, after emailing twice to ask what the situation was since I never heard anything, I received a copy and pasted rejection email from a noreply address. No feedback or anything. After 3 interviews, the least you would expect of an up-and-coming company like Tiktok would be a few pointers of where I could improve - instead, I basically had to drag a rejection out of them since it looked like they expected me to just 'take the hint' without any communication. Probably a bullet dodged in the end.
If you want a company who is going to value its employees, or its employee candidates, I would look elsewhere.