There were 7 interviews total if you include the HR related phone calls. 2 Leetcode style tests, an 8 hour takehome assignment and a "system design interview" which is actually just a UI design interview, not a system design interview... Still not sure why they labelled it as such. This took place over the course of about 2 months. After all was completed, I got a phone call from the recruiter saying that I aced every single technical interview, but they didn't hire me because I didn't know the "definition" of the "event loop" in Node.js. It's true, I didn't know exactly what it was called in my interview with the hiring manager, and I could tell immediately he thought I was a moron. However: A. You can literally google what terms mean. B. The event loop, and understanding of it, is a concept I leverage successfully on a daily basis at my job, and successfully used in the coding assignment THEY sent me, which they said was one of their best submissions. So my advice to Data Dog would be to make the interview with the elitist, gatekeeping hiring manager at the beginning of the process, instead of at the end so that misunderstandings like this can be avoided, and 2 months of my time can avoid being wasted.

1 HR screening ( 30 min ) Then 1 Initial coding interview (45 min) Then Onsite React interview (1h) Frontend System design interview (1h) System design interview ( with something I actually worked on ) ( 45 min ) Behavioral interview ( 45 min )