Quick email questions, followed up by call, followed up by react coding challenge, followed up by conversation with two engineers. The biggest problem was that the react coding challenge was setup for "failure" due to inappropriately using React and mutating data from under you. This is sort of a company engineering code smell that if they can't design a simple code challenge in an idiomatic way what else are they doing poorly?
The company seems to be circling the drain a bit putting all of their future into one product. Everyone I did talk to seemed nice enough though.