I talked to the HR person, then had a 30 min technical interview with the ML lead, then they sent me an over the weekend coding challenge. Then I was called in for a second tech interview. The first interview was easy, the second was difficult. The first interview was completely unnecessary, and the coding challenge was a complete waste of time. they should've just done the more difficult technical interview first, and then short list for coding challenge... wasted a lot of my time.

The process included 3 steps: 1) HR phone screening: Very typical HR questions like "What are you good at?", "What aren't you good at?" ..etc. Mainly talk about yourself and your recent work. Note: that was a somewhat negative experience, because it was clear that the HR person did not read my resume at all, and had qualitatively bad answers for my questions about the company. 2) Technical phone interview: 30 mins interview with questions regarding basic concepts in Machine learning. 3) On-site technical interview: 1 hr interview with 2 engineers.