Avionics Engineering applicants have rated the interview process at SpaceX with 4 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 50% positive. This is according to Glassdoor user ratings.
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30 minute phone call with the avionics manufacturing lead. Asked about technical experience, previous internships, and engineering questions. Was asked why I was the right candidate for the job, and implied the work would be very demanding. The phone call was a bit intense, but positive.