Coders Crushby Napplied AI
Level 1

Senior Engineer Track

Master the fundamentals of system design. Learn to design moderately complex systems, understand trade-offs, and communicate your designs effectively.

Key Skills

End-to-end system designScalability patternsDatabase designAPI designCaching strategiesLoad balancing

10

Total Problems

4

Easy

6

Medium/Hard

0

Expert

Medium Level

(6 problems)
Design a Rate Limiter
medium
Infrastructure
Design a distributed rate limiting system to protect APIs from abuse and ensure fair usage.
30 min
rate-limitingapiredisdistributed-systems
Design Twitter/X
medium
Social & Media
Design a microblogging platform like Twitter with features like posting tweets, following users, timeline, and trending topics.
45 min
social-networktimelinetrendingfan-out
Design Instagram
medium
Social & Media
Design a photo-sharing social network like Instagram with features like posting photos, following users, and a personalized feed.
45 min
social-networkfeedphoto-sharingcdn
Design WhatsApp/Messenger
medium
Real-time Systems
Design a real-time messaging application like WhatsApp supporting 1:1 chat, group chat, media sharing, and delivery receipts.
45 min
messagingwebsocketreal-timechat
Design Netflix/YouTube
medium
Social & Media
Design a video streaming platform like Netflix or YouTube supporting video upload, transcoding, and adaptive streaming.
45 min
video-streamingcdntranscodingrecommendation
Design Uber/Lyft
medium
Real-time Systems
Design a ride-sharing application like Uber supporting real-time driver matching, location tracking, and fare calculation.
45 min
ride-sharinggeospatialreal-timematching

Fundamentals

(4 problems)
Design a URL Shortener
easy
Data Storage
Design a URL shortening service like bit.ly or TinyURL. The system should generate short URLs from long ones and redirect users.
30 min
url-shortenerkey-value-storehashingcaching
API Gateway vs Load Balancer
easy
Fundamentals
Explain the differences between an API Gateway and a Load Balancer. When would you use each?
15 min
fundamentalsnetworkingarchitecture
CAP Theorem Explained
easy
Distributed Systems
Explain the CAP theorem and its implications for distributed system design.
45 min
distributed-systemstheorydatabases
Horizontal vs Vertical Scaling
easy
Fundamentals
Compare horizontal scaling (scaling out) vs vertical scaling (scaling up). What are the trade-offs?
45 min
fundamentalsscalabilityinfrastructure