trivago Software Engineer Data Integration interview questions

Took one day, applied online at trivago website. Got an email for an on-site interview at Leipzig office. Had interview with HR, Team Lead and Head of the department all at the same time. I would say one of the best interviews I have experienced, very friendly and relaxed interview environment. Everyone introduced themselves and the company first, then some basic HR questions. After that a technical round from basic trivia to a high level architecture and case study. Then they showed me the office setup, everyone seemed to be very nice and friendly. Got the job offer via email the same day.