Three calls: two with co-founders, one with a team lead. Trivial stuff: talk about your experience, and one leetcode super easy. Sent an informal (yet remarkable) offer shortly thereafter, though lacking lots of details (no paperwork). When I asked some clarifying questions about the offer and asked to connect with team members, they retracted the offer the very next day! This says a lot about the culture and not having a single call with a potential team member is worrisome, do they have any? Before accepting, try to talk to former workers if you can't speak with the current ones.