Configuration Management System Low-Level Design
What is a Configuration Management System? A configuration management system externalizes application settings — database URLs, feature flags, API keys, […]
Design, System Design
Design, System Design
CDN Design Low-Level Design
What is a CDN? A Content Delivery Network (CDN) is a distributed network of edge servers placed close to users
Algorithms, Coding Interview Questions
String Algorithm Patterns for Coding Interviews
Why String Algorithms Matter in Interviews String problems are ubiquitous in technical interviews at Google, Meta, Amazon, and Microsoft. Key
Design, System Design
Audit Log System Low-Level Design
What is an Audit Log? An audit log is an immutable, append-only record of every significant action taken in a
Algorithms, Coding Interview Questions
Graph Algorithm Patterns for Coding Interviews
Why Graph Algorithms Matter in Interviews Graph problems appear constantly in technical interviews because they model real systems: social networks
Design, System Design
Time-Series Database Low-Level Design
What is a Time-Series Database? A time-series database (TSDB) is optimized for storing and querying data points indexed by time:
Design, System Design
GDPR Data Deletion System Low-Level Design
What is GDPR Right to Erasure? GDPR Article 17 gives EU users the “right to be forgotten” — they can
Design, System Design
Multi-Tenancy System Low-Level Design
What is Multi-Tenancy? Multi-tenancy means a single application instance serves multiple customers (tenants), with each tenant’s data isolated from others.
Design, System Design
Image Processing Service Low-Level Design
What is an Image Processing Service? An image processing service handles on-demand or batch transformations of images: resize, crop, compress,
Design, System Design
Newsletter System Low-Level Design
What is a Newsletter System? A newsletter system manages subscriber lists, drafts and schedules email campaigns, personalizes content, and tracks
Design, System Design
Social Login System Low-Level Design
What is Social Login? Social login (OAuth 2.0 / OpenID Connect) lets users authenticate with an existing identity provider (Google,
Design, System Design
Notification Preferences System Low-Level Design
What are Notification Preferences? Notification preferences let users control which notifications they receive, via which channel (email, push, SMS, in-app),
Design, System Design
Media Upload Service Low-Level Design
What is a Media Upload Service? A media upload service handles ingest, validation, processing, and storage of user-generated files: profile
Design, System Design
Leaderboard System Low-Level Design
What is a Leaderboard System? A leaderboard ranks users or entities by a score, updated in real time. Use cases:
Design, System Design
Search Indexing System Low-Level Design
What is a Search Index? A search index enables fast full-text queries over large datasets. Without an index, searching 1