Skip to main content

Command Palette

Search for a command to run...

👉 “Top 7 System Design Interview Questions You Can’t Ignore in 2025”

Published
2 min read

Intro:
System design interviews are no longer reserved for senior engineers — even mid-level and entry-level devs are facing them in 2025.
The key to cracking them is knowing which questions appear again and again. Let’s look at the 7 most important ones.


🔹 1. Design a URL Shortener (Like bit.ly)

  • Concepts tested: Hashing, Database design, Scalability.

  • Interview tip: Always mention collision handling.


🔹 2. Design a Cache System (Like Redis)

  • Concepts: Caching strategies (LRU, LFU), Expiry, Consistency.

  • Interview tip: Mention trade-offs between speed and memory.


🔹 3. Design a Load Balancer

  • Concepts: Round robin vs weighted, Failover, Health checks.

  • Interview tip: Always show a diagram.


🔹 4. Design a Chat Application (Like WhatsApp)

  • Concepts: WebSockets, Message queues, Storage models.

  • Interview tip: Don’t forget real-time delivery guarantees.


🔹 5. Design a Rate Limiter

  • Concepts: Token bucket, Leaky bucket, Fixed window counters.

  • Interview tip: Explain why rate limiting is critical for APIs.


🔹 6. Design YouTube (Video Streaming System)

  • Concepts: CDN, Sharding, Metadata management, Thumbnails.

  • Interview tip: Stress on high availability.


🔹 7. Design an E-commerce System (Like Amazon)

  • Concepts: Inventory management, Payment flows, Recommendations.

  • Interview tip: Talk about microservices and scalability.


✅ Final Thoughts

In 2025, these 7 problems cover 80% of what system design interviews actually ask.
Don’t just memorize answers — focus on trade-offs (scalability vs cost, speed vs consistency).


👉 Call to Action :
I’ve created detailed step-by-step diagrams, flowcharts, and interview notes for these questions here:
FullStackPrep.dev – System Design Interview Prep

More from this blog

W

What is .NET Core? The Modern Framework

6 posts