1. initial tech screen
2. coderbyte/hackerrank (3 questions or so)
3. 1-hour whiteboarding session with engineer
4. ghosted
No email, no follow up, no phone call. Just a grand old waste of time.
These guys are 99% funded by gov't contracts; not only will they waste your tax dollars, they'll also waste your time. Skip.
Oh and the whiteboarding session was 50% non-interactive listening to an engineer ramble.