There were multiple interviews with different members of the data science team, a group presentation of a prior project, and an interview with the COO before any offer was made.

I had a first round screening interview, which seemed to go well based on the interviewer's reaction. She said she would get back to me about scheduling a second interview, but never did. I sent a follow up email, but received no reply. Later on, I learned independently that they had hired someone whose background was in security (not data science) for this role.