I applied online. After 3 weeks or so, I received an email from a technical manager setting up a phone interview, and a link to a GitHub coding challenge. The challenge asked me to write a REST web service that received data from a url, do some computation, and returned computed data to the provided client file. It took me four days of about 16 hours in total. It was because I had no idea what REST means going in. I spent most of the time understanding the term, looking up the specific framework they want me to use, and figuring out a way to test my code. I emailed the manager two versions of my untested code with questions about testing. The manager was kind enough to give me some guidance. After finally capable of testing my code after trying multiple failed approaches, I fixed the bugs, and sent a third version. After this, there is a one hour phone interview with the technical manager who reached out to me. We talked about my resume, and my solution for the challenge. A few days after that, there is a one hour video interview with the same manager, and manager of another team that he works closely with. In this interview, more behavioral questions, and some description about the work Collins does.