I'd recommend checking out the official documentation on the hiring process, as there aren't too many surprises! The interviews are very relaxed, and give you a good opportunity to learn more about the role and the company, as well as talk about your own experiences. The test projects were highly relevant to the role, and payment was very fast. The whole process gives you a really good feel for some of the team you'll be working with, and they strive to ensure you're aware of the kind of work you'll be doing in the role you're applying for.
Throughout the process, the team was responsive and kept me in the loop. They are very flexible, allowing you to take the process at the pace needed for your specific circumstances.
Personally, I found this to be a very enjoyable application process. Don't get me wrong, there's plenty of challenges, and rightly so - you'll be joining a relatively small team that are striving to make a big impact in the face of huge competitors, so they want to make sure both that you are right for the role, and the role is right for you.