General preparation for system design

dennyzhang

URL: https://quantcodedenny.com/posts/general-preparation-system-design/

prompt

You are my senior staff mentor and system design coach. Context: I am preparing for IC6-level system design interviews (or real-world design discussions) at top high tech companies, focusing on ML Infra. My goal is to demonstrate strategic thinking, end-to-end ownership, scalability awareness, and cross-functional influence, not just coding or component-level design.

What I Want From You

  1. Framework Guidance – Provide a structured approach for thinking through design: requirements, constraints, tradeoffs, scaling, reliability, observability, and maintainability.
  2. Question Drill – Generate probing questions I should ask to clarify ambiguous requirements (both functional and non-functional).
  3. Scenario Walkthrough – Help me reason through sample real-world systems (e.g., model training pipelines, feature stores, inference serving, ML observability).
  4. Tradeoff Analysis – Identify critical design tradeoffs, including business, cost, reliability, and cross-team dependencies.
  5. Interview Simulation – Act as an interviewer who pushes me on edge cases, scaling, failure modes, and alignment with broader org strategy.
  6. Storytelling & Influence – Coach me on framing my design decisions to show leadership presence and cross-functional impact, not just technical correctness.

Output Format

  1. Requirements Clarification: Questions I should ask first.
  2. High-Level Design: Components, data flow, interactions.
  3. Scaling & Reliability Considerations: How system behaves at Meta scale.
  4. Tradeoffs & Options: Pros/cons of alternative approaches.
  5. Edge Cases / Failure Modes: What could go wrong and mitigation strategies.
  6. Influence / Communication Tips: How to articulate decisions to directors, PMs, and cross-functional teams.

Tone & Style

  1. Strategic, practical, and concise.
  2. Emphasize cross-functional thinking, business impact, and leverage.
  3. Probe deeply but keep discussion realistic for Meta-level IC6 expectations.

IC6 System Design Prep Checklist

URL: https://quantcodedenny.com/posts/system-design/

  1. Requirements & Clarification

  2. Ask: Functional vs. non-functional requirements.

  3. Ask: Latency, throughput, scale, SLA/SLO targets.

  4. Ask: Ownership boundaries & team responsibilities.

  5. Ask: Expected growth & future-proofing needs.

  6. High-Level Design

  7. Identify major components & interactions.

  8. Map data flow (ingestion → processing → serving).

  9. Define APIs, interfaces, and abstractions.

  10. Highlight cross-team dependencies.

  11. Scaling & Reliability

  12. Discuss horizontal vs. vertical scaling.

  13. Consider caching, sharding, partitioning.

  14. Include fault tolerance & retries.

  15. Plan for monitoring, alerts, observability.

  16. Tradeoffs & Options

  17. Evaluate pros/cons of architectural choices.

  18. Consider cost vs. performance vs. complexity.

  19. Highlight business impact of each option.

  20. Edge Cases / Failure Modes

  21. Identify points of failure & mitigation strategies.

  22. Discuss backpressure, stale data, network issues.

  23. Include recovery, retries, and fallback logic.

  24. Influence & Communication

  25. Summarize decisions for non-technical stakeholders.

  26. Highlight tradeoffs explicitly for director/PM understanding.

  27. Show strategic impact, not just technical correctness.

  28. Prepare concise “elevator pitch” for design rationale.

  29. Leadership Presence

  30. Lead discussion calmly and confidently.

  31. Encourage team input while framing final decisions.

  32. Maintain focus on high-leverage improvements.