Data Masking System Low-Level Design
5 min read What is Data Masking? Data masking replaces sensitive data (PII, payment cards, SSNs) with realistic-but-fake values for use in non-production […] Read article
System Design
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System Design
Learn to design scalable, reliable systems that handle millions of users. System design interviews test your ability to architect real-world applications, considering tradeoffs, scalability, and best practices.
Core Topics:
Scalability: Load balancing, horizontal vs vertical scaling
Storage: Databases (SQL vs NoSQL), caching (Redis, Memcached)
Reliability: Replication, failover, disaster recovery
Performance: CDNs, caching strategies, database indexing
Common Design Questions:
Design URL shortener (bit.ly)
Design rate limiter
Design Twitter/Instagram feed
Design messaging system (WhatsApp)
Design file storage (Dropbox)
Interview Level: Senior engineers (L5+) at FAANG companies. Requires 3-5+ years experience to tackle effectively.
Preparation: Study system design patterns, understand distributed systems fundamentals, and practice mock interviews.
System Design
Geofencing System Low-Level Design
5 min read What is Geofencing? Geofencing defines virtual geographic boundaries (circles or polygons) and triggers actions when a tracked entity (user, vehicle, Read article
System Design
User Onboarding Flow System Low-Level Design
5 min read What is an Onboarding Flow System? An onboarding flow guides new users through setup steps to reach the “aha moment” Read article
System Design
Price Alert System Low-Level Design
5 min read What is a Price Alert System? A price alert system notifies users when a tracked item’s price drops below their Read article
System Design
CDN Design Low-Level Design
5 min read What is a CDN? A Content Delivery Network (CDN) is a distributed network of edge servers placed close to users Read article
System Design
Configuration Management System Low-Level Design
5 min read What is a Configuration Management System? A configuration management system externalizes application settings — database URLs, feature flags, API keys, Read article
System Design
Audit Log System Low-Level Design
5 min read What is an Audit Log? An audit log is an immutable, append-only record of every significant action taken in a Read article
System Design
GDPR Data Deletion System Low-Level Design
5 min read What is GDPR Right to Erasure? GDPR Article 17 gives EU users the “right to be forgotten” — they can Read article
System Design
Time-Series Database Low-Level Design
5 min read What is a Time-Series Database? A time-series database (TSDB) is optimized for storing and querying data points indexed by time: Read article
System Design
Image Processing Service Low-Level Design
5 min read What is an Image Processing Service? An image processing service handles on-demand or batch transformations of images: resize, crop, compress, Read article
System Design
Multi-Tenancy System Low-Level Design
5 min read What is Multi-Tenancy? Multi-tenancy means a single application instance serves multiple customers (tenants), with each tenant’s data isolated from others. Read article
System Design
Newsletter System Low-Level Design
5 min read What is a Newsletter System? A newsletter system manages subscriber lists, drafts and schedules email campaigns, personalizes content, and tracks Read article
System Design
Notification Preferences System Low-Level Design
5 min read What are Notification Preferences? Notification preferences let users control which notifications they receive, via which channel (email, push, SMS, in-app), Read article
System Design
Social Login System Low-Level Design
6 min read What is Social Login? Social login (OAuth 2.0 / OpenID Connect) lets users authenticate with an existing identity provider (Google, Read article
System Design
Leaderboard System Low-Level Design
4 min read What is a Leaderboard System? A leaderboard ranks users or entities by a score, updated in real time. Use cases: Read article