Planet Software Engineer, Backend interview questions

The first round consisted of a phone screen with a senior engineer, who proceeded to quiz me on one-off Linux and Python questions, most of which were fairly basic. I was then given a take home assignment which asked me to implement a RESTful API. The spec was somewhat vague and seemed hastily written, though was overall fairly easy. A few days after submitting, I received an automated no-reply rejection email, with no feedback on my performance. I tried my best to get in contact with my original interviewer to ask for feedback, but received no response. It was unfortunate to feel that I wasted my time with this interview process because the company genuinely seems very interesting.