System Design Interview: Zero to Hero 🚀

A comprehensive, step-by-step guide to mastering system design interviews from beginner to advanced levels. This repository is structured like a book with progressive learning paths.

Learning Path 📚

Phase 1: Foundations (Weeks 1-2)

• Target: Complete beginners
• Topics:
  • What is system design?
  • Client-server architecture
  • Basic HTTP/REST concepts
  • SQL vs NoSQL databases
  • Simple monolithic architecture

Phase 2: Core Principles (Weeks 3-4)

• Target: Intermediate learners
• Topics:
  • Scalability: Horizontal vs Vertical
  • Availability & Reliability
  • Latency vs Throughput
  • CAP theorem
  • Consistency models

Phase 3: Design Patterns (Weeks 5-6)

• Target: Building competence
• Topics:
  • Load balancers
  • Caching strategies (Redis, Memcached)
  • Database sharding
  • Replication
  • Message queues
  • CDN fundamentals

Phase 4: Component Deep Dive (Weeks 7-8)

• Target: Advanced understanding
• Topics:
  • API gateways
  • Rate limiting
  • Service discovery
  • Circuit breakers
  • Distributed locks

Phase 5: Case Studies (Weeks 9-10)

• Target: Application of knowledge
• Systems to design:
  • URL shortener (TinyURL)
  • Social media (Twitter)
  • Ride-sharing (Uber)
  • Video streaming (Netflix)
  • Messaging (WhatsApp)

Phase 6: Advanced Topics (Weeks 11-12)

• Target: Expert level
• Topics:
  • Distributed systems
  • Event-driven architecture
  • Real-time systems
  • Search systems (Elasticsearch)
  • Big data pipelines

The 4-Step Framework for Any System Design Interview 🔄

Step 1: Requirements Clarification (5-10 mins)

• Functional requirements
• Non-functional requirements
• Scale estimation
• Define API signatures

Step 2: High-Level Design (10-15 mins)

• Component diagram
• Data flow
• Technology choices
• Database schema

Step 3: Deep Dive (15-20 mins)

• Scalability considerations
• Bottleneck identification
• Failure handling
• Security aspects

Step 4: Wrap-up (5 mins)

• Summarize design
• Discuss trade-offs
• Mention improvements
• Q&A

Essential Resources 🌟

Must-Read Books

1. "Designing Data-Intensive Applications" by Martin Kleppmann
2. "System Design Interview" by Alex Xu (Vol 1 & 2)
3. "The Pragmatic Programmer" by David Thomas & Andrew Hunt

Online Courses

• Grokking the System Design Interview (Educative)
• System Design Primer
• High Scalability

YouTube Channels

• Gaurav Sen - System Design
• Tech Dummies - System Design
• CodeKarle - Mock Interviews
• Exponent - System Design

Practice Platforms

• Pramp - Free mock interviews
• Interviewing.io - Anonymous practice
• LeetCode - System design discussions

Useful Tools

• Draw.io - System architecture diagrams
• Excalidraw - Hand-drawn style diagrams
• Miro - Collaborative whiteboarding

Common Interview Questions by Company 🏢

FAANG Companies

• Facebook: Design Facebook News Feed, Facebook Messenger
• Amazon: Design Amazon Shopping Cart, AWS S3
• Apple: Design iMessage, Apple Photos
• Netflix: Design Netflix, Video Streaming Service
• Google: Design Google Search, Google Docs, YouTube

Other Tech Companies

• Uber: Design Uber backend, Surge Pricing
• Twitter: Design Twitter, Twitter Search
• Dropbox: Design Dropbox, File Sync Service
• Airbnb: Design Airbnb, Booking System
• Spotify: Design Spotify, Music Recommendation

Estimation Cheatsheet 📊

Storage

• 1 character = 1 byte
• Average tweet = 280 characters ≈ 280 bytes
• 1 million tweets = 280 MB
• 1 billion tweets = 280 GB

Throughput

• Requests per second (RPS) calculation
• Peak vs average traffic
• Read vs write ratio

Memory

• Cache size estimation
• Session storage
• In-memory databases

Pro Tips for Success 💡

1. Always start with requirements - Don't jump into solutions
2. Think out loud - Interviewers want to see your thought process
3. Make reasonable assumptions - State them clearly
4. Focus on trade-offs - Every design has pros and cons
5. Ask questions - Clarify ambiguities
6. Draw diagrams - Visualize your architecture
7. Practice timing - Mock interviews are crucial
8. Stay updated - Follow industry trends

Contributing 🤝

We welcome contributions!

How You Can Help:

• Add new system design problems
• Improve existing solutions
• Translate to other languages
• Fix typos and errors
• Add more resources

License 📄

This project is licensed under the MIT License - see the LICENSE file for details.

Support ❤️

If you find this helpful, please:

• ⭐ Star this repository
• 🍴 Fork it
• 🔗 Share with friends
• 🐛 Report issues
• 💡 Suggest improvements

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Remember: System design is not about knowing everything, but about thinking through problems systematically. Practice, learn from each interview, and gradually you'll go from zero to hero!

Start your journey today! 🚀