After a short HR call, I received a complex task of 3d robotic navigation and two weeks to solve it, using specific platform that I found out works only on specific versions of Ubuntu after a few days of compilation issues. No consulting fee offered, didn't meet anyone in the team, didn't know the salary or details about the job. I went with good will despite this and presented my partial work and asked about these things mid way before continuing, only to receive a generic rejection two weeks later. Generally bad experience, very asymmetric in terms of investment. I suggest asking for a consulting fee.