OpenNet (Taiwan) Software Engineer, Backend interview questions

Positive: 1. The feedback from HR is quick, it took 3 days after I submitted the online assessment and my resume. Although they say to reply within 24h, I think that less than one week is acceptable. 2. The online assessment is on HackerRank, with 3 questions from easy to hard, to be completed in 70/80 minutes. Negative: 1. They send you a private message on LinkedIn with the job offer and the link to the online assessment. Then they ask for the resume (including your personal data) without even sending a connection request. 2. I spent 1 hour of my time, completed the online assessment SUCCESSFULLY, provided my resume, and got a private message like: "sorry we are looking for a more experienced developer". No call, no email. 3. The job offer said "Backend developer", not Senior Backend developer 4. There was no indication about years of experience 5. I have more than 5 years of professional experience with the technology they use, and this technology came out 6 years ago. Moreover, my experience literally applied to each point of the job offer, I don't know what kind of experience they are looking for.