Signavio Senior JavaScript Engineer interview questions

1. Call with HR 2. Inside interview (Technical and soft skill questions) 3. Technical task for ~4h. Create a table on React 4. Inside interview 4a) Whiteboard session 4b) Lunch 4c) Review with HR 4d) Chat with CTO (not in my case) Before chatting with CTO, I was called by HR and said that I failed the interview and they don't want to waste time. I asked what was wrong? HR said he doesn't know and he promised that sent me feedback. I didn't get any feedback and even don't know what was wrong. I think it's disrespectful.