AppNexus Software Engineer New Grad interview questions

First round video interview, Onsite Interview at their small office in Montreal. First round video interview is a coding question and few follow-ups. The onsite includes a behavioral, a coding, and a system design (for new grads). People ay their Montreal office are basically all SDEs, and they are very friendly. The university recruiter, who worked for Nexus for more than 3.5 years, was really unprofessional. She arranged a phone call with me right before the final interview, just to ask my nationality. (instead of asking if I'm authorized to work). It's obviously unlawful in the US and Canada.