I was approached by their recruiter, and the process initially went very smoothly. After completing a take-home assignment, however, communication stopped completely.
After a few weeks, I followed up to ask for an update, making it clear that I was fine with not being selected, but would appreciate closure. I never received a response, even after several months.
Being rejected is part of the process, but completely cutting off communication after a candidate invests time in an assignment is disappointing. At minimum, an automated rejection email would be expected.