A recruiter contacted me and offered to participate in a coding interview. When I asked about the specific position, the answer was that after the interview process, they would decide what position would be suitable for me.

So, I decided to give it a try.

1st Round - Coding Interview. I was given a Users & Groups management sample and a PDF with issues. The interviewer was nice, but I recommend starting from unit tests (TDD is key) and explaining everything you do so no questions will be asked. In case anything goes wrong, the interviewer will ask questions. Duration: 60 minutes. On-site.

2nd Round - System Design (45 minutes) and Abstract Coding (45 minutes) interview. System Design: You will need to talk about your previous projects in detail. Abstract Coding: I was given a connection pool example, so you need to implement an abstract language connection pool. Afterwards, the interviewers will change requirements, and you will update accordingly. I didn't find it that hard, but I recommend thinking about concurrency and patterns like Wrapper, Delegate, or Proxy. I was rejected in the 2nd round because I didn't go deep enough into the technical details of my previous project (i.e., System Design).

I recommend going as deep technically as possible. I discussed high-level architecture and delved into technology and framework choices, drawbacks, and trade-offs, but I still wasn't technically deep enough. I even asked the interviewers what details they wanted to hear, but received no good answer. They are managers and cannot ask deep questions, so they will simply listen to you and reject you if you were not able to sound technically deep. So, my recommendation: you have to speak as deeply as possible. Even though they call the session System Design, it has nothing to do with System Design; it's more about what you did technically and what problems you encountered during that task.

The next day, I received a standard templated email stating I was rejected due to "could not explain the project deep enough." There was no promised "we will assess you and offer you a proper position."

Recruiters simply go through a bunch of people and bring them to interviews; that's it.

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