Zalando Senior Software Engineer(Search) interview questions

Applied for this role. Process described briefly below. #1 - Phone interview with the technical recruiter/HR. Straightforward Hr questions dealing with the motivations of joining zalando and relocation to Berlin. #2 - Codility test. with 3 questions. #3 - Technical screen with the team lead and team manager. Went through my resume and asked some managerial questions. after this got a mail for a final interview. 4, 1 hour interviews back to back #4 - Algorithms and approach to problems. #5 - API design and structuring #6 - Programming with online code editor. #7 - Final round with HR regarding the salary and other details. Promised me to get back in a week. One of the worst interviews I've had in my life. This interview process gives a ver clear look into their culture. Having spent so much of time to interview with them , the least they could have done is send me a mail saying we wont move forward with my reply. I mailed and contacted them multiple times and every time got the same answer, (Recruiter is on leave, interviewers on leave) we'll get back within a week! very unprofessional and lack basic ethics to conduct interviews. vile and horrible experience. Waste of time .