I applied online and was referred through a friend.

First, I was contacted by a recruiter, and we set up a call. She wanted to know what I've worked on. We chatted about programming languages, my interests, and "why SpaceX". We arranged a technical phone screen with a member of the team.

The technical phone screen was very good. I was supposed to talk about a technical project I'd worked on and my contributions. I picked the system I work on at my current job. This was not difficult; it would only be difficult for someone trying to BS. They just want to know if you contributed, how, and why. Don't stress out here; just be yourself!

After the phone call from the recruiter, we set up a take-home code challenge. It is not a LeetCode problem! It is a fun little problem that you can probably solve if you code at your day job. The most complex coding thing I did here was recursion and understanding Big O trade-offs. This problem is about translating requirements into code.

The final round is a technical interview. This interview is significantly easier than a Facebook interview. No LeetCodes, mostly just trivia. For example: "How does a hash map work? How does a C++ vtable work? How does an OS store memory?" I did not get all of these questions. I would have known them right out of college, but that was a decade ago. I answered most of them, and the ones I missed were some of the more out-there ones.

I received the offer, but SpaceX cannot match even 60% of my current salary, and I cannot do that to my family right now.

In C++, what is a vtable and how does it work?

Why SpaceX?

How does a hash map differ from a set?

What is the trade-off between parallelism in Python vs. C++?

Lots of questions about CPU out-of-order execution and data hazards, compiler optimizations, compiled languages vs. interpreted languages.