The interview process was pretty standard for Facebook: phone interviews, followed by a one-day on-site session.

Recruiters and interviewers were nice and friendly, but the overall impression was smeared by unclear feedback during and after the interview. When they constantly say, "yes, great, awesome, cool, makes sense, etc.," it feels like, "Wow, I'm doing great!" But afterward, they reject you, stating you didn't do what they wanted and should have performed better.

The architectural interview is one of the most unpredictable, so be careful choosing your approach.

The main problem I see is that interviewers don't give you any hints when you deviate from the expected thinking direction. They may also initiate a discussion that consumes available time, making it almost impossible to provide a full, expected answer. Well, I'm not a mind reader.

Anyway, visiting the campus and talking to engineers was a great experience. It was worth it.

Signed NDA.

But phone interview questions were the same as mentioned many times here:

• Flatten an array
• Optimize a function
• Implement a simple Observable