⏱ 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

⏱ 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

⏱ 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

⏱ 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

⏱ 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

⏱ 5 min read What is a Media Upload Service? A media upload service handles ingest, validation, processing, and storage of user-generated files: profile Read article

⏱ 6 min read What is a Search Index? A search index enables fast full-text queries over large datasets. Without an index, searching 1 Read article

⏱ 7 min read What is Order Fulfillment? Order fulfillment covers the steps from a confirmed order to the item delivered to the customer: Read article

⏱ 6 min read Requirements Track stock levels across multiple warehouses for millions of SKUs Reserve inventory when an order is placed; deduct when Read article

⏱ 7 min read Requirements Users share a unique referral code or link to invite new users Referrer earns a reward when a referred Read article

⏱ 7 min read What Does a DNS Resolver Do? The Domain Name System (DNS) translates human-readable domain names (www.example.com) into IP addresses (93.184.216.34). Read article

⏱ 7 min read Requirements One-on-one and group messaging (up to 500 members) Message delivery with read receipts (sent, delivered, read) Message history persistence Read article

⏱ 7 min read What is a Dead Letter Queue? A Dead Letter Queue (DLQ) holds messages that could not be processed successfully after Read article

⏱ 7 min read What is a Feature Store? A feature store is a centralized repository for ML features. It solves the “feature engineering Read article

⏱ 7 min read Requirements Users can post comments on content items (posts, videos, products) Threaded replies (nested comments) up to N levels deep Read article