Uber's interview process can be confusing. It starts with a take home assignment. If you clear this, it should be an onsite with a specific team. But it's in the hands of the recruiter to decide your next steps.
In my case, the recruiter came back to me a week later saying that my profile is not right for a backend role. When I mentioned that I am a backend engineer, she said I need to change my resume to show that. I changed the resume (added 4 words and changed my title to say backend) and suddenly this was a profile that managers liked - or so I was told. I think my resume was not shown to an engineering manager initially and once I added the word backend, it was shown. Then I had an onsite - 2 technical, 1 design, 1 bar raiser and 1 manager round. Design round seemed to concentrate highly on DB - which DB within NoSQL - trade offs, etc.
Overall the engineers seemed decent. But the recruiters were pretty inconsiderate with rude remarks like - your profile is a junior profile, we don't consider internships (I have no internship exp but 8+ years of full time exp), we only want backend engineers, etc. They basically look for keywords in your resume highlighted and bolded. If not present, they do as they please.