1st round: some online algorithm exercises
2nd round: fill-in some information in a spreadsheet
3rd round: I received an email with a 1-2 days notice that three interviews would take place in a span of 4-5 hours.
I mentioned that I would be unavailable at these times, since I also work at night. After that, I never got back from them, even after sending another email asking if I was still in the process.
Normally companies politely request some time availability from candidates before scheduling any one-2-one interviews. Not getting back any email from them was a big disappointment for me.
They contact you inviting you to participate in a selection process, and then this is how they treat you.