🏗️ System Design — 1000 Interview Questions¶
Goal: Comprehensive preparation for System Design interviews. 1000 unique questions across 4 levels, collected from the internet and FAANG sources.
Date: 2026-04-27 Language: Questions and explanations are in English (industry standard).
📑 Sections¶
| # | Level | File | Questions | Difficulty | For whom |
|---|---|---|---|---|---|
| 1 | 🟢 Junior | 01-junior-level.md | 250 | Easy | 0–2 years of experience, bootcamp / student |
| 2 | 🟡 Middle | 02-middle-level.md | 250 | Medium | 2–5 years, mid-level engineer |
| 3 | 🟠 Senior | 03-senior-level.md | 250 | Hard | 5–8 years, senior / L5 |
| 4 | 🔴 Professional | 04-professional-level.md | 250 | Expert | Staff / Principal / L6+ |
| 📖 | Sources | 05-sources.md | — | — | Web sources & references |
| 🏗️ | Design Problems ("Design X") | 06-design-problems.md | 1000 + 50 OOD | Mixed | Real interview prompts |
Total: 1000 concept questions + 1000 "Design X" problems + 50 OOD problems = 2050.
🧭 Roadmap — Preparation¶
- Junior — learn the fundamentals: HTTP, DB, cache, LB, basic APIs, simple designs
- Middle — real-world designs (Twitter, Bitly, Yelp), CAP, sharding, MQ, microservices
- Senior — distributed consensus, geo-replication, complex trade-offs, real-time pipelines
- Professional — org-wide architecture, migrations, build-vs-buy, deep internals, leadership
🎯 What's in each section¶
🟢 Junior (1–250)¶
- Networking & Web Basics (1–30)
- Database Basics (31–60)
- Caching Basics (61–80)
- Architecture Basics (81–110)
- Load Balancing Basics (111–125)
- Security Basics (126–145)
- API Basics (146–165)
- Storage & Files Basics (166–180)
- Common Junior-Level Designs (181–215)
- Concepts & Terminology (216–235)
- DevOps & Deployment Basics (236–250)
🟡 Middle (251–500)¶
- Core Distributed Concepts (251–280)
- Database & Sharding (281–320)
- Messaging & Streaming (321–350)
- Microservices & APIs (351–380)
- Real-World Designs (381–430)
- Reliability & Performance Patterns (431–470)
- Caching Strategies (471–490)
- Search & Indexing (491–500)
🟠 Senior (501–750)¶
- Advanced Distributed Systems (501–540)
- Geo-Distribution & Multi-Region (541–570)
- Scalability Deep Dive (571–610)
- Advanced Data Pipelines (611–640)
- Trade-offs & Architecture Choices (641–680)
- Advanced Security (681–710)
- Performance & Internals (711–740)
- Failure & Recovery (741–750)
🔴 Professional (751–1000)¶
- Staff+ Architecture & Leadership (751–790)
- Extreme Scale Designs (791–830)
- Database & Storage Internals (831–870)
- Specialized Systems (871–910)
- Migration, Modernization & Org Design (911–940)
- Theory, Internals, Open Problems (941–970)
- Open-ended Architecture & Vision (971–1000)
🎓 Usage tips¶
| Level | Time per question | Format |
|---|---|---|
| Junior | 2–5 minutes | Verbal answer, key terms |
| Middle | 30–45 minutes | Whiteboard sketch + components |
| Senior | 45–60 minutes | Trade-off justification |
| Professional | 1–2 hours | Written answer in RFC format |
For a mock interview, pick 3–5 questions per level, answer under a time limit, then record yourself and critique the result.
Created: 2026-04-27 · Version: 1.0 · Total: 1000 unique questions