Top 50 System Design Questions for Technical Interviews

System design interviews can be super intimidating, right? I remember sweating through my first few, feeling like I was trying to build a skyscraper with LEGOs. I’ve put together a list of the top 50 system design questions that can help you prep, so you don't have to feel lost.

Let's break down these questions and get you ready to rock your next interview.

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Why This List Matters

System design interviews test your ability to create scalable, efficient, and reliable systems. Knowing the common questions and how to approach them can make all the difference.

I’ve seen many candidates nail the coding rounds but stumble in the system design discussions. This list is designed to help you:

• Understand the breadth of topics covered.
• Practice problem-solving in a structured way.
• Develop a strong foundation in system architecture.

How to Use This List

• Review Each Question: Understand the problem and potential solutions.
• Practice Aloud: Explain your thought process as you design.
• Consider Trade-Offs: Discuss the pros and cons of different approaches.
• Use Real-World Examples: Relate the problems to systems you know.
• Check Out Coudo AI: Use the platform for hands-on practice and feedback.

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Top 50 System Design Questions

Here’s the list, grouped by category to help you focus your preparation.

1. Fundamental Design

1. Design a URL Shortener: How would you create a service like TinyURL?
2. Design a Rate Limiter: How do you prevent abuse of an API?
3. Design a Web Crawler: How do you efficiently crawl the internet?
4. Design a Notification System: How do you send real-time updates to users?
5. Design a Recommendation System: How do you suggest relevant content to users?
6. Design a Search Engine: How would you build a simple search engine?
7. Design a Social Media Feed: How do you display updates from friends in real-time?
8. Design an E-commerce Platform: How do you manage products, orders, and payments?
9. Design a Cloud Storage Service: How do you store and retrieve files reliably?
10. Design a Distributed Cache: How do you improve application performance with caching?

2. Scalability and Performance

1. Design a Load Balancer: How do you distribute traffic across multiple servers?
2. Design a Consistent Hashing System: How do you distribute data evenly across servers?
3. Design a Distributed Message Queue: How do you handle asynchronous tasks?
4. Design a Database Sharding System: How do you scale a database horizontally?
5. Design a Content Delivery Network (CDN): How do you deliver content quickly to users worldwide?
6. Design a System for Handling High Traffic: How do you manage spikes in user activity?
7. Design a Monitoring System: How do you track the health and performance of your system?
8. Design a Fault-Tolerant System: How do you ensure your system stays up during failures?
9. Design a System for Real-Time Analytics: How do you process and analyze data in real-time?
10. Design a System for A/B Testing: How do you compare different versions of a feature?

3. Data Storage and Management

1. Design a Key-Value Store: How do you store and retrieve data using keys?
2. Design a Relational Database: How do you structure and query data with relationships?
3. Design a NoSQL Database: How do you handle unstructured or semi-structured data?
4. Design a Graph Database: How do you store and query data with complex relationships?
5. Design a Time-Series Database: How do you store and analyze data over time?
6. Design a Data Warehouse: How do you store and analyze large volumes of historical data?
7. Design a Data Lake: How do you store data in its raw format for future analysis?
8. Design a Data Pipeline: How do you move data from one system to another?
9. Design a System for Data Backup and Recovery: How do you protect your data from loss?
10. Design a System for Data Consistency: How do you ensure data is accurate across multiple systems?

4. Specific Applications

1. Design a Chat Application: How do you handle real-time messaging between users?
2. Design a Video Streaming Service: How do you deliver video content to users efficiently?
3. Design an Online Gaming Platform: How do you handle real-time interactions between players?
4. Design a Ride-Sharing App: How do you match riders with drivers in real-time?
5. Design a Food Delivery Service: How do you manage orders, deliveries, and payments?
6. Design a Social Networking Site: How do you manage user profiles, connections, and content?
7. Design a Mobile Payment System: How do you handle secure transactions on mobile devices?
8. Design a Smart Home System: How do you connect and control devices in a home?
9. Design a Healthcare Management System: How do you manage patient data and appointments?
10. Design a Supply Chain Management System: How do you track products from manufacturing to delivery?

5. Advanced Topics

1. Design a Blockchain System: How do you create a decentralized and secure ledger?
2. Design a System for Machine Learning Model Deployment: How do you deploy and scale machine learning models?
3. Design a System for Anomaly Detection: How do you identify unusual patterns in data?
4. Design a System for Natural Language Processing: How do you process and understand human language?
5. Design a System for Computer Vision: How do you process and understand images and videos?
6. Design a System for IoT Data Management: How do you handle data from a large number of devices?
7. Design a System for Edge Computing: How do you process data closer to the source?
8. Design a System for Serverless Computing: How do you run code without managing servers?
9. Design a System for Quantum Computing: How do you leverage quantum mechanics for computation?
10. Design a System for Augmented Reality: How do you overlay digital content onto the real world?

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How to Tackle These Questions

For each question, follow these steps:

1. Clarify Requirements: Ask questions to understand the scope.
2. Outline the Architecture: Sketch out the main components and their interactions.
3. Discuss Data Storage: Choose the appropriate database and data structures.
4. Consider Scalability: Discuss how to handle increased load and traffic.
5. Address Reliability: Explain how to ensure the system remains available during failures.
6. Think About Security: Discuss how to protect the system from attacks.
7. Optimize Performance: Identify and address potential bottlenecks.
8. Consider Trade-Offs: Discuss the pros and cons of different design choices.

Here's a little secret. The best way to prepare is to practice! You can level up your skills with machine coding exercises. Check out Coudo AI's LLD interview questions for hands-on practice.

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FAQs

Q: How do I start preparing for system design interviews?

Start with the fundamentals: scalability, databases, and networking. Then, practice with common system design questions.

Q: What are the key areas to focus on in system design?

Focus on scalability, reliability, data consistency, and security. Understand the trade-offs between different design choices.

Q: How important is communication during system design interviews?

Very important! Explain your thought process clearly and engage with the interviewer. It’s about showing how you think, not just what you know.

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Wrapping Up

I hope this list of top 50 system design questions helps you prepare for your next technical interview. System design is a skill that improves with practice, so keep at it! If you want to deepen your understanding, check out more practice problems and guides on Coudo AI.

Good luck, and keep pushing forward! The more you practice, the better you'll get at designing scalable, efficient, and reliable systems. System design questions are all about problem solving so keep at it!