I had a mixed experience interviewing at Twitter. They had their standard Engineering Manager round and a technical screener. Then the final virtual interview with 4 rounds (Project Deep Dive, ML Design, Systems Design/Coding, Topgrading). Each round had 2 interviewers assessing you. The interviewers themselves were a mixed bag as well. For their Systems Design round, I had great interviewers who clearly knew how to interview. The ML Design round had guys who couldn't explain the problem well or pose a question well. Perhaps, its because you are trying to interview for ML virtually and it's better to whiteboard in person. I wish the interviewer just gave a problem and utilized an online app to design ML model instead of making it an interactive session. Project Deep Dive was pretty neutral, one of the guys kept dropping connection, so be prepared for that too. So this was the technical interview experience, overall pretty neutral. Now, I had a read a lot about Twitter's recruiters being finicky but I actually experienced it first hand. They are actually as sloppy as you might have heard. First, they told me my technical screener is a coding round but I got greeted for ML problem solving/knowledge. Second, for the final interview rounds, they said there will coding but in fact there wasn't any coding and I spent all the time on Leetcode and Hackerrank. Lastly, it took the recruiter 3 days to inform me that they had cancelled my Topgrading interview round. In every step of the process, I had to email the recruiters twice before I got any response. My final suggestion for someone interviewing for this position would be to focus on more the ML model designing more than coding and keep bugging the recruiters because they don't respond. Hope this helps in knowing what to expect.