Search Engine Architecture
Search engine architecture for crawling, indexing, and ranking web pages.
How It Works
Step-by-step mechanics behind protocols, infrastructure, and system internals, with attention to state changes, dependencies, and failure paths.
Proximity Service
Proximity service design for indexing locations and querying nearby results.
Amazon S3 Upload Flow
Amazon S3 upload flow through authentication, object writes, metadata, and durability.
How Push Notifications Work on Phones and PCs
Push notifications flow through platform brokers such as APNs and FCM.
Stock Exchange System Design
Stock exchange design for order matching, latency control, and auditability.
Chat Application Design
Chat system architecture for connections, ordering, presence, and message delivery.
Google Maps System Design
Google Maps design across location updates, tile serving, and route computation.
Experiment Platform Architecture
Experiment platform architecture for traffic allocation, event capture, and analysis.
Designing a Google Docs-Style Editor
Collaborative editing through operation ordering, conflict resolution, and convergence.
Payment System Architecture
Payment system flow through durable events, idempotent execution, ledgers, and settlement.
Internationalization System Design
Internationalisation design for locale-aware text, data, and user flows.
Live Streaming Architecture
Live streaming through encoding, segmentation, adaptive bitrate delivery, and CDNs.
Redis Chat Application Architecture
Redis chat architecture using pub/sub for rooms, fan-out, and connection state.
Quadtree
Quadtree indexing for partitioning two-dimensional space and pruning searches.
How Google and Apple Maps Blur License Plates and Faces
Street View blurring uses detection models and irreversible image obfuscation.
Gmail System Design
Gmail architecture across mail transfer, storage, indexing, and spam defence.
Email Delivery Flow
Email delivery through SMTP relays, DNS lookups, queues, and mailbox placement.
How AirTags Work
AirTags combine Bluetooth beacons, nearby Apple devices, and the Find My network.