First a recruiter reached out, and I decided to go ahead with the process. First there was a technical phone interview, that involved some DOM manipulation. That interview was nice, and the recruiter said that we could move on the the next step, which was a 10h UX project. I asked why they needed that step instead, since I already had many relevant Open Source projects that would be easy to review by any other dev. So she told me that this was their process, and I should not spend more than 10h. The project was easy enough, I put a lot of effort into making the code clean, and delivering a good UX that match requirements and mocks. Still it got rejected without any clear feedback, all the recruiter said is that my code was very good but the "Senior Engineer" was expecting more of an overall design (whatever it is), probably my mistake was not writing the code EXACTLY the way he would.

Note: I went through this in late 2021 - early 2022. Might have changed since then. Initial interview process took a few weeks. First spoke to a recruiter who assessed my basic skills, then went through several rounds of technical interviews, including a take-home exercise that had clearly not been updated in a very long time (they had a REST API you were supposed to hit, and all the data in it was 7 years old, plus it didn't actually work due to CORS restrictions, so I had to write my own proxy for it). Then some live white-boarding, which wasn't too terrible, mostly just general questions and problem-solving skills. Now the bad part: after passing all the interview rounds and getting a stamp of approval, you are placed in a pool of vetted candidates. You're then supposed to be matched with a team/role. The team leads interview you to check your fit and interest with the role, and then have to make an argument internally for why they should hire you. This is OK in theory, but in practice, it just dragged on and on and on. From the time I started interviewing with them to the day I finally got an offer (which I turned down to go to a startup), it took EIGHT MONTHS.