I applied through a recruiter.

HR and the first tech interview went well. In the second Zoom interview, both interviewers didn't like to turn their cameras at all, although I was asked to ensure my camera was working, which wasn't very respectful. Some of the questions were really specific to Rust language implementation details that you don't usually remember well unless working on the language compiler itself, which felt weird. There were some questions where I did my best to give answers, none of which were satisfactory, and I wasn't explained what the answer was that the interviewer wanted to hear. In general, I felt like the guys tried to prove their own excellence over me rather than evaluate my fit and experience.

How can you make sure the code is production-ready before deploying it?