🗺️ System Design: Google Maps (Frontend Interview Guide)
Category: system-design
Difficulty: hard
Target Level: Senior Frontend Engineer / Staff Engineer Duration: 45-60 minutes Interview Focus: Frontend Architecture, Performance, State Management, Rendering Interview Approach & What Interviewers Look For When asked to design Google Maps in a frontend interview, interviewers are evaluating: Architecture Thinking: Can you break down a complex UI into manageable components? Performance Awareness: Do you understand rendering bottlenecks and optimization strategies? Trade-off Analysis: Can you articulate why you chose one approach over another? Real-world Experience: Have you dealt with similar challenges (canvas rendering, large datasets, real-time updates)? Scalability: Can your design handle millions of data points without crashing? Pro Tip: Start with clarifying questions, then move from high-level architecture to specific technical deep dives. Clarifying Questions (First 5 minutes) Before diving in, ask these questions to scope the problem: Functional Scope: "Should we support just viewing maps, or also search, directions, and real-time traffic?" "Do we need offline support?" "What platforms? Web only, or also mobile web?" Non-Functional Requirements: "What's the expected scale? Millions of concurrent users?" "Performance targets? Should we maintain 60fps during pan/zoom?" "Accessibility requirements? WCAG compliance?" Technical Constraints: "Can we use existing libraries like Mapbox GL or Leaflet, or build from scratch?" "Browser support? Modern browsers only, or legacy IE11?" High-Level Architecture (Draw This!) [code example] Key Talking Points: Separation of Concerns: UI, State, Rendering, and Data are decoupled Hybrid Rendering: DOM for UI controls, Canvas/WebGL for map Client-Heavy: Most rendering happens in the browser for performance...