What problem does it solve? Interviewers and candidates lack a structured framework for system design rounds, where questions often drift into trivia recitation instead of testing real design reasoning like requirement clarification, capacity estimation, and failure-mode analysis. ## Core Features & Use Cases - Topic Ladders: Covers requirement clarification, capacity estimation, storage selection, caching, sharding, consistency and idempotency, message queues, rate limiting, high availability, distributed IDs, and observability, each with progressive difficulty steps. - Good vs Bad Question Patterns: Contrasts trivia-style prompts (e.g., "explain CAP") with scenario-driven questions that force trade-off reasoning and numeric estimation. - Resume-Based Hooks: Maps resume keywords like "high concurrency", Redis, message queues, and sharding to targeted follow-up probes. - Use Case: An interviewer preparing a second-round backend interview loads this Skill to generate a short-link service design question, then probes the candidate on QPS estimation, cache layering, and 301 vs 302 redirect choices. ## Quick Start Generate a system design interview question on秒杀 (flash sale) for a senior backend candidate, including capacity estimation steps and follow-up probes on overselling prevention.
