Applied through recruiter. Process took 3 weeks total. Phone screen was one coding problem (Merge Intervals). Passed to onsite with 4 rounds: 2 coding, 1 system design, 1 culture fit.
First coding was design in-memory file system with mkdir, ls, addContentToFile operations. Used HashMap with Trie-like structure, took 35 mins. Interviewer pushed on concurrency so discussed read/write locks.
Second coding was deserialize binary tree. Classic problem, used BFS with queue, got O(n) solution in about 25 mins.
System design was Netflix video streaming ,went super deep on CDN architecture, adaptive bitrate streaming, encoding pipeline, handling millions of concurrent streams. This round lasted 75 mins and they really grilled me on video-specific tech.
Culture fit was all about "freedom and responsibility" dealing with ambiguity, high performance culture, etc.
Used Gotham Loop for prep. The file system and tree serialization questions were exact matches from their Netflix bank. System design I'd seen similar but Netflix goes way deeper than other companies on domain-specific stuff.