Going to push back on the usual advice for xAI behavioral prep because I think people are optimizing for the wrong thing.
A lot of prep resources tell you to rehearse STAR stories. xAI's behavioral questions aren't looking for polished STAR delivery. They're looking for something messier and more specific: do you make decisions fast with incomplete information, and do you own the outcome either way.
The questions I got in my loop (two behavioral rounds, split across phone screen and onsite): "Tell me about a time you had to make a call with almost no data. What did you decide and what happened." "Describe a project that failed. What was your part in it." "Tell me about a time you disagreed with your manager or team and what you did." "What's the fastest you've ever shipped something significant. What did you cut."
Notice a theme. Speed, ownership, conflict, trade-offs. This maps to a company that moves very fast and expects engineers to have opinions.
What I think they're NOT looking for: the clean "here's the situation, here's my action, here's the perfect outcome" arc. Real stories have friction. I actually did better when I described a project that went sideways than when I tried to give a perfect success story.
Also: they ask about Grok and AI directly in some rounds. "What do you think about [specific Grok capability]" type questions. Worth actually using the product before your loop so you're not stumbling.
One more thing. The hiring bar on "fast" seems cultural. If your examples are all "we took 3 months to align stakeholders," that's probably a mismatch signal for them regardless of outcome.