The interview process is very casual but long.

First, there's a HackerRank challenge.

Then, a screening interview with the recruiter, where they asked basic questions and some simple quiz-type technical questions commonly found online.

Next, a pair programming challenge, which is also relatively simple with basic math involved.

Finally, there are two more interview stages that are a bit more hands-on and challenging.

The interview with the recruiter included basic questions, such as the difference between let and var, or even asking what certain code snippets would do. I'd say know your ES6 before the screening.

The last step interview question was about building a UI, and the final interview question was almost about building an algorithm.