Data Export Service Low-Level Design
5 min read What is a Data Export Service? A data export service allows users to download their data in bulk — CSV, […] Read article
System Design
System Design
Consent Management System Low-Level Design
6 min read What is Consent Management? Consent management records and enforces users’ privacy preferences: which data collection and processing activities they have Read article
System Design
Pagination System Low-Level Design
5 min read Why Pagination Design Matters Returning all results for a query — all 10 million orders, all 500K users — is Read article
System Design
API Versioning System Low-Level Design
5 min read Why API Versioning Matters APIs are contracts between your service and its consumers. Once published, breaking changes — renaming fields, Read article
System Design
Two-Factor Authentication System Low-Level Design
5 min read What is Two-Factor Authentication? Two-factor authentication (2FA) requires users to verify their identity with a second factor beyond their password: Read article
System Design
Subscription Management System Low-Level Design
6 min read What is Subscription Management? A subscription management system handles recurring billing: plans, upgrades/downgrades, trial periods, proration, cancellations, and payment retries. Read article
System Design
Search History System Low-Level Design
5 min read What is a Search History System? A search history system records a user’s past searches, enables autocomplete from personal history, Read article
System Design
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
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
Algorithms, Coding Interview Questions
Interval Algorithm Patterns for Coding Interviews
5 min read Why Interval Problems Matter in Interviews Interval problems appear in scheduling, calendar, and range queries — and in coding interviews 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