Redpanda Data Senior Software Engineer interview questions

I started interviewing for a senior role which got filled after 2 interview rounds - 1 with HM and 1 C++ round. Then I was asked if i'd be interested to interview for a Software engineer role. Then I had another C++ round, HM round and a take home assignment using Seastar. The assignment is real fun! Throughout, the interviewers were really nice and spoke as if they were genuinely keen. They said they had another interviewer ahead of me in process and made me hurry with the rounds. After the assignment presentation, had a culture-fit round and then they ghosted me for a week. Then came back and mumbled something that said they chose someone else, citing NO reason. I was fine with the rejection, but wanted feedback. After all, I have engaged with them for nearly 5-6 rounds! You don't need 5 rounds to "ghost" someone as unworthy. Absolute waste of time. Please don't interview with them.