Facebook employee referred me. The interview process consisted of one telephonic round followed by four onsite rounds:

• One cultural fit
• One design
• Two coding

The interview process was very smooth, and all the interviewers were very friendly. Most of the questions in the coding rounds focused on algorithm fundamentals. They also expect clean coding with proper testing.

The design round was more like a discussion you would have with your teammate, suggesting pros and cons of each method.

Clean code, test cases, scalable design, high-level design.