Vaadin Software Engineer interview questions

I have passed pre-screening coding challenge, passed several interviews, including the one with CEO. After that had the official offer, and accepted it. After that I had a Skype meeting with the team. After that I was invited to visit the team in office and said "We will make final hiring decision after your visit" (???). I suggested the manager to give me a test assignment if they have some doubts on my skills. But they did not reply anything to that. I asked the manager of what shall I learn before the visit, and learned that. Obtained visa, visited them, spend a half of day in their office learning the docs and fixing bugs in their samples. After that I was said "We revoke your offer". Because you "do not fit the team well enough", and "not enough enthusiastic". It looks like something is terribly wrong with their hiring process. To be honest, I would not recommend to deal with that company in any way at all. And, if you've decided to apply, be prepared to jump up to the ceiling showing how you're excited by them and swear on blood that it was a blue dream of all your life to work with them. May be that helps. p.s. I can prove each and every word in this review.

I took phone interview, answered questions and explained working experience base on resume, then interviewer told me to take onsite interview. I was very interested in this company and canceled a famous company's onsite interview invitation to make schedule with Vaadin. During onsite, after I answered questions, the interviewer said he want to stop to continue conversation with me and let me out without reason. Waste of time. This is the most unfriendly interview I have ever experienced.