I applied online. The process took 4 months. I interviewed at SpaceX in Mar 2016
Interview
I actually didn't get hired my first time through the interview process. On the first go around, I had one interview in the Structures department, and was told a few (I think 3-4) days later that SpaceX would not be pursuing an offer for me. I stayed in contact with my interviewer, however, and a few months later, emailed him about my continued interest and passion for working at SpaceX. In a matter of hours, the hiring manager reached out to me for a potential Fall internship for a manufacturing engineering position. I interviewed with a manager and a team lead, and was called a couple days later about being extended an offer.
I applied through an employee referral. The process took 3 weeks. I interviewed at SpaceX (New York, NY) in Mar 2016
Interview
Series of phone interviews. Was interviewed by HR and then two different managers. They really went through my resume. Asked about my projects and created hypothetical engineering questions based on the things I've designed and built.
Interview questions [1]
Question 1
If you had to make 5,000 units of the part you made and you needed them within a month how would you do it? How will the part differ with this manufacturing process vs the previous one you used. How do you design for manufacturability?
I applied through college or university. The process took 2 weeks. I interviewed at SpaceX (Hawthorne, CA) in Jun 2012
Interview
Very technical. They want to dig into details of how you executed a project, not just hear about it on a high level. Need to fully understand the concepts behind the project you are presented, as there will be experts on those concepts present. Don't make things up, this is way worse than not knowing something.