System Design

⏱ 6 min read Geospatial Data Fundamentals Geospatial queries are common in production systems: “find the 10 nearest restaurants,” “is this user inside a […] Read article

⏱ 7 min read Core Entities Cart: cart_id, user_id (NULL for guest), session_id (for guest carts), status (ACTIVE, ABANDONED, CHECKED_OUT), currency, created_at, updated_at, expires_at. Read article

⏱ 6 min read Core Entities Home: home_id, owner_id, name, address, timezone, created_at. Room: room_id, home_id, name, floor_number. Device: device_id, home_id, room_id, name, type Read article

⏱ 6 min read Why Distributed Caching? A single application server’s in-memory cache is lost on restart and not shared across instances. A distributed Read article

⏱ 6 min read What is an API Marketplace? An API marketplace (like Stripe, Twilio, RapidAPI, or AWS API Gateway) lets external developers discover, Read article

⏱ 6 min read Core Entities Tenant: tenant_id, name, slug, plan, custom_domain, storage_quota_gb, created_at. (Multi-tenant: each customer organization is a tenant with isolated content.) Read article

⏱ 6 min read Feed Architecture Overview A social feed shows users content from people and pages they follow, ranked by predicted engagement. The Read article

⏱ 7 min read Core Entities Member: member_id, user_id, program_id, tier (BRONZE, SILVER, GOLD, PLATINUM), points_balance, lifetime_points (never decrements — used for tier calculation), Read article

⏱ 7 min read The Three Pillars of Observability Metrics: numerical measurements over time (request rate, error rate, latency percentiles, CPU usage). Low cardinality, Read article

⏱ 6 min read Data Lake vs. Data Warehouse A data warehouse stores structured, schema-on-write data optimized for SQL analytics (Redshift, BigQuery, Snowflake). A Read article

⏱ 6 min read Core Entities Customer: customer_id, name, email, phone, default_address, stripe_customer_id. Restaurant: restaurant_id, name, address, location (lat/lng), cuisine_type, rating, is_open, prep_time_minutes, operating_hours. Read article

⏱ 6 min read Core Entities User: user_id, email, name, quota_bytes, used_bytes. Document: document_id, owner_id, name, mime_type, current_version_id, parent_folder_id, is_deleted (soft delete), created_at, updated_at. Read article

⏱ 6 min read What is a Blockchain Explorer? A blockchain explorer is a read-only interface to blockchain data — like a search engine Read article

⏱ 6 min read RTB Architecture Overview Real-Time Bidding is the programmatic ad auction system that runs every time a user loads a web Read article

⏱ 6 min read Authorization Models ACL (Access Control List): per-resource list of who can do what. Simple but does not scale — updating Read article