I applied through another source. The process took one week.

It went straight to a take-home coding assignment after the HR phone screen. Two days were given to complete it, much like the other reviews say. They are willing to provide feedback when asked. It was a fairly demanding question if trying as hard as possible. They're looking for production-level code, by the way, even though it doesn't explicitly say that. I think they want to see how much you'll put up with and the time you'll devote to them before even talking to an engineer.

There was a full C++ multithreaded matching engine with UDP network connectivity and packets. They spell out correctness as the goal with many opportunities for "extra credit" to go an extra few miles with implementation.