I didn't end up getting an offer.

Due to NDA, I cannot explicitly write down the questions, but if you look at the last 150 questions on Glassdoor and CareerCup, you'll do fine. I did fine in the coding rounds, which I'll get to in a bit.

Usual advice: Practice a lot of whiteboarding for questions and be ready to talk extensively about your projects, architecture, and design.

Screening Round: I applied to Facebook by getting connected to a recruiter through a colleague and friend. The process started in Seattle, and I opted for an in-person onsite interview for the screening round (they have this option for locals in Seattle/California).

The interview went well; I figured out how to solve the question with optimal time and space complexity. I made some mistakes here and there while writing the solution down, but the interviewer didn't seem to mind. Contrary to what I had heard, he wasn't too anal about syntax (it also helped that I write in C#, a language he wasn't very familiar with).

Onsite Round: I received an email from the recruiter stating they wanted to move forward and invited me onsite. I was like, "Cool!"

I took around 2 weeks to prepare and also tried to do design questions. I felt a bit underprepared regarding design and tried to make up for it in the last few weeks by watching videos on cloud architecture (and open-source stuff like Hadoop, Kafka, and Storm).

The onsite was pretty straightforward. The first round was a career fit/discussion, and I think I did pretty well. It mainly involved some behavioral questions and many diagrams around the architecture of my current and previous projects.

The second round was the one I messed up. The question was around designing an existing Facebook feature (as a hint, think about the various add-ons you see on FB and Instagram, like Chat, Search, latest friend-related news, or popular links). When you really dig into designing this feature, it's quite complicated and requires a reasonable amount of knowledge around distributed data storage, etc., etc.

You need to nail this round to get into Facebook (in my personal opinion). I'm guessing they adjust their expectations based on your years of experience.

There was a lunch, which was informal, and two more coding rounds where they asked questions very similar to the ones I had practiced. I made some silly mistakes here and there, but again (due to practice), I came up with optimal time/space complexity answers.

I got my result exactly one week from my onsite date. No offer, but I learned a lot.

Design round.