Tl,dr: I don't think the application is worth the time doing the assignment.I've got a first interview with the HR. After, I went to the second interview with the CTO and the HR. Interview went well, both HR and CTO were very nice. I was a little bit worried though because I asked about work-life balance and they answered about wanting "passionate people".They asked me to do an assignment (a path planner on a specific map with ROS, implemented in either C++ or Python). It took me ~30 hours. Feedbacks were good but they asked for performance improvements. They asked for performance improvement, I improved the performance of the PRM from 30 seconds to planning average to 4 seconds. Feedback was again very good.

They "liked the way I improved the planner and the changes I implemented".Another candidate was taken because he did a better job at the test. While I think the assignment give a very good overview to what you could do at the job, it's very time consuming. Mine took ~30 hours to do. I have to admit that, compared to other job application, being refused felt worse because of the time invested in the application. But again, it's my fault, because I think I invested myself emotionally way too much into that one.I don't think the application is worth the time assignment, but again, that's just my experience. The whole process, from interview to final refusal, took 2 months. The HR and CTO were nice and professional.

Do you prefer to work in team or alone ?