You now understand company-specific patterns.
Google: Scale, algorithms, distributed systems. Show the math.
Meta: Product sense, social dynamics, real-time systems.
Amazon: Leadership principles woven into technical decisions.
Startups: Speed, pragmatism, MVP thinking.
Fintech: Correctness, compliance, audit trails.
Research your target company. Read engineering blogs. Understand what they build and value. Congratulations on completing this roadmap. You're ready for system design interviews.