Wärtsilä Software Engineer Interview Questions
& Process

I was introduced to the project manager and some developers, and then the PM showed me the product they were working on. They asked me to introduce myself, and then the technical interview began. It was mostly C++ questions, followed by 3 coding questions.

The interview process started with a CV screening, no online assessment involved. Then, there was a technical interview covering many topics like OOP, C++ specifics, DSA, and general math. For C++ specifics, there were many questions on multi-threading, for example, what would happen if atomic variables are not used in a specific code scenario, which depends on compiler and CPU architecture. OOP had standard questions. Pointers were also discussed, but not smart pointers. Math questions included probability, statistics, geometry, and linear regression. It was quite difficult, but manageable if prepared. The most challenging part was the unexpected C++ specific questions related to compiler and CPU architecture. I also forgot the O(log n) Fibonacci solution and only remembered the DP linear time solution, though they helped me reach the O(log n) one. The biggest hurdle was understanding the interviewer's questions due to their English and microphone quality, which was a significant issue.

I did the coding challenge they sent over and got most of the problems solved. I tried to get some feedback and followed up by email, but never heard back. About two months later, I got an email saying I didn't get the job.