Staff Mechancal Engineer applicants have rated the interview process at SpaceX with 3 out of 5 (where 5 is the highest level of difficulty) and assessed their interview experience as 100% positive. To compare, the company-average is 53.4% positive. This is according to Glassdoor user ratings.
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Recruiter screening then technical interview. Seemed to go well but I got the sense they were looking for someone with more experience. Asked fundamental mechanical engineering questions about first principles applied to spaceX projects.