I applied through a recruiter. The process took 4 weeks. I interviewed at SpaceX (Los Angeles, CA) in Oct 2018
Interview
Phone screen followed by invite to on site interview. 4 hour interview was scheduled, 10 hour interview actual. 1 hour presentation by interviewee to a panel with questions, followed by one on one meetings with multiple people.
Interview questions [1]
Question 1
Example of hard technical problem you solved?
Buoyancy problem, what happens to water level if something dropped out of a boat in a container.