I applied for Fetch Rewards online and heard back the next day, they sent me a take home assignment that was build this API. You could use whatever tools and languages you like. You should pay close attention to the data, as it doesn't outline everything in the specifications so you have to make some assumptions, nothing too crazy. Be sure to be thorough and explain decisions you made. You have to leave documentation on how to build your project and how to use it as well. After I sent that in I got a zoom interview with one of the engineers. It was a good interview and the interviewer was very nice. He asked questions about how I thought through my take home assignment and why I did certain things. Then he asked questions about my work experience and such. Overall a nice interview. They got back to me the next day and asked if I wanted to proceed to an onsite interview which would be 5 and half hours long, I was super excited about this. However, they wanted to bring me on as an "intern" for 3 months before bringing me on for a perm hire. I'm not sure if this is something they do for all entry level positions or if they weren't sure about me. I was looking for a permanent job (since I'm not an intern at my current company) so I had to decline sadly.
Overall the interview process was quick and everyone was nice. I wish they would have been upfront about the internship from the get go, since I spent a pretty good amount of time on this.