All 99 articles, sorted alphabetically
System Design: Rate Limiting
Read article →System Design: Circuit Breaker Pattern - AICassindra
Deep dive into the Circuit Breaker pattern for building resilient distributed systems.
Read article →Bloom Filters
Bloom Filters
Read article →The Saga Pattern: Managing Distributed Transactions
The Saga Pattern: Managing Distributed Transactions
Read article →System Design: Load Balancing - AICassindra
Deep dive into Load Balancing strategies, algorithms, and implementation patterns in distributed systems.
Read article →Airbnb Architecture
How Airbnb runs search, availability, pricing, and payments across 6M+ listings.
Read article →Airbnb Smart Pricing Architecture
The ML system that suggests nightly prices to hosts across millions of listings.
Read article →Alipay Super-App Architecture
China's other super-app: mobile payments + credit + wealth management at 1.3B users.
Read article →Amazon Shopping Cart Architecture
How Amazon keeps carts consistent across sessions, devices, and unavailable items.
Read article →API Gateway Architecture
The gateway pattern: single entry for many services + built-in auth, rate-limit, transform.
Read article →API Gateway Patterns
Backend for Frontend, response aggregation, and cross-cutting concerns at the edge.
Read article →API Versioning Strategies
How to evolve APIs without breaking existing clients.
Read article →ATM End-to-End Architecture
From card insertion to cash dispense: every service, network hop, and reconciliation step.
Read article →Autocomplete / Typeahead Architecture
Prefix trees, ranking, and sub-100ms latency for search suggestions.
Read article →Bulkhead Pattern
How to prevent one slow service from starving all thread pools.
Read article →Cache Aside vs Write-Through vs Write-Behind
The three cache-integration patterns, when each wins, and their consistency tradeoffs.
Read article →Cache Invalidation Strategies
TTL, write-through invalidation, versioning, and pub/sub. Trade freshness vs load.
Read article →Cache Stampede Prevention
The problem: hot key expires, 1000 concurrent requests slam the DB. Three solutions.
Read article →CDN Architecture
How content delivery networks minimize latency by caching close to users.
Read article →CDN Cache Hierarchy
Multi-tier caching that turns global content into local responses.
Read article →CDN Architecture
How a modern CDN uses anycast + edge compute to serve billions of requests globally.
Read article →Circuit Breaker Pattern
The three states + how to configure for your traffic + failure profile.
Read article →CQRS + Event Sourcing Architecture
Split writes (commands) from reads (queries), persist events instead of state.
Read article →Credit Card Payment Flow Architecture
The complete authorization + capture + settlement flow across acquirer, network, and issuer.
Read article →Database Sharding Architecture
How to split a table across N databases, with routing + rebalancing.
Read article →Designing a Real-Time Chat System (1M concurrent users)
End-to-end architecture for a WhatsApp-scale chat system, from connection layer to message storage.
Read article →Designing an API Gateway
Routing auth rate-limit observability in one tier.
Read article →Designing a Distributed Cache (Memcached/Redis-style)
Consistent hashing replication and eviction policies.
Read article →Designing an Event-Driven Order System
State machine, idempotency, and the recovery story.
Read article →Designing a Feature Flag System
Targeting, rollout, kill switch, and audit.
Read article →Designing a File Upload Service (S3-style)
Resumable uploads multipart deduplication and lifecycle policies.
Read article →Designing a Metrics Aggregation System
Time-series ingest pre-aggregation and downsampling.
Read article →Designing a Notification Service
Push email SMS multi-channel fan-out with retries.
Read article →Designing a Payment System
Idempotency keys ledger reconciliation and PCI scope.
Read article →Designing a Quota System
Token bucket, sliding window, distributed counters.
Read article →Designing Search at Scale
Inverted index, ranking, freshness, personalization.
Read article →Designing Search Autocomplete
Trie-based prefix matching with personalization.
Read article →Designing Uber Dispatch System
Geo-indexing matchmaking and surge pricing.
Read article →Designing a URL Shortener (TinyURL-scale)
Hashing collision strategies database choice and analytics.
Read article →Designing YouTube Recommendation Ranking
Two-tower retrieval candidate generation and learning-to-rank.
Read article →Directory-Based Sharding
Explicit key-to-shard mappings for maximum flexibility and per-tenant isolation.
Read article →Discord Architecture
How Discord handles millions of concurrent voice channels + huge text servers with low latency.
Read article →Distributed Cache Architecture
How a horizontally-scaled cache handles millions of keys across N nodes, with the resharding strategy.
Read article →Distributed Cache Consistency Models
Strong vs eventual consistency options for distributed caches, with fault behavior.
Read article →DNS System Architecture
The distributed lookup system that turns names into IPs, with caching + zone hierarchy.
Read article →DoorDash Architecture
How DoorDash coordinates customers, restaurants, and Dashers with real-time dispatch.
Read article →Dropbox File Sync Architecture
How Dropbox syncs files across devices with delta sync + block-level dedup.
Read article →Elasticsearch Cluster Architecture
How Elasticsearch distributes an index across nodes with sharding + replication.
Read article →Email Delivery Architecture
How email gets from sender to recipient through anti-spam gauntlets.
Read article →Event-Driven Microservices Architecture
How services communicate via events instead of synchronous calls, with the failure modes.
Read article →Facebook Messenger Architecture
Meta's messenger stack: MySQL-derived TAO + custom binary protocol + optional Signal E2E.
Read article →Real-Time Fraud Detection System Architecture
How payment platforms score millions of transactions/second in under 100ms.
Read article →Geo-Partitioning
Sharding by geography for compliance + user latency wins.
Read article →Google Drive + Docs Real-Time Collaboration Architecture
Operational Transformation and CRDTs behind multi-user document editing.
Read article →Google Maps Real-Time Traffic Architecture
How aggregated GPS pings from billions of phones become live traffic overlays.
Read article →Google Search Architecture
How Google indexes 100B+ pages and returns relevant results in <200ms.
Read article →Grab Architecture
Grab's evolution from ride-hailing to rides + food + payments + more across 8 countries.
Read article →GraphQL Architecture
Query language, resolvers, N+1 problem, and DataLoader patterns.
Read article →gRPC + Protobuf Architecture
How gRPC delivers 10x smaller payloads and streaming across languages.
Read article →Hash Sharding
Hash-based sharding: mechanics, hotspot avoidance, rebalancing tradeoffs.
Read article →iCloud Sync Architecture
How Apple keeps notes, photos, contacts, and messages in sync across every Apple device.
Read article →Idempotency Key Pattern
How idempotency keys enable safe retries without duplicate charges or double-writes.
Read article →iMessage Architecture
How iMessage delivers end-to-end encrypted messages across Apple devices using APNs + cloud sync.
Read article →Instagram Feed Generation Architecture
Photo + video feed with ranking, stories, and reels at Facebook-scale infrastructure.
Read article →Kafka Partition Architecture
How Kafka's partition model scales throughput and delivers ordered messages within a key.
Read article →L4 vs L7 Load Balancer Architecture
Where each operates in the stack, decision points, and when to use which.
Read article →LinkedIn Architecture
How LinkedIn serves 1B members with a mix of Kafka, Espresso, and Voldemort at Microsoft-scale infra.
Read article →Meta Threads Architecture
How Threads launched in 5 days by leveraging Instagram's infrastructure.
Read article →PayPal P2P Architecture
How PayPal processes billions of P2P transfers with balance-based ledger + bank integration.
Read article →Range Sharding
Range-based sharding for time-series, geo queries, and ordered scans.
Read article →Rate Limiter Architecture
Two canonical rate limiter algorithms, side by side, with an inline architecture diagram.
Read article →Rate Limiting Strategies Compared
Token bucket, leaky bucket, fixed window, sliding window — when each one is wrong.
Read article →Recommendation System Architecture
Two-tower models, candidate generation, ranking, and serving at 200M+ user scale.
Read article →Reddit Architecture
How Reddit ranks 100K+ subreddit posts and comments with the classic hot algorithm.
Read article →REST API Design Deep Dive
Resource modeling, verb semantics, versioning, and hypermedia for real REST APIs.
Read article →Robinhood Trading Architecture
Zero-commission mobile-first trading and the payment-for-order-flow economics.
Read article →Amazon S3 Object Storage Internals
How S3 achieves 11 nines durability + infinite scale via erasure coding + partition placement.
Read article →Saga Pattern for Distributed Transactions
Long-running business transactions via compensating steps instead of 2PC.
Read article →Service Discovery Patterns
How microservices find each other in dynamic infrastructure.
Read article →Service Mesh Architecture
How a sidecar-based mesh separates business logic from cross-cutting concerns.
Read article →Shard Rebalancing Strategies
How to move data safely when adding, removing, or splitting shards.
Read article →Signal Protocol Architecture
How Signal's double ratchet gives forward secrecy and post-compromise recovery per message.
Read article →Slack Architecture
How Slack indexes billions of messages and delivers real-time updates to workspaces of thousands.
Read article →Snapchat Ephemeral Messaging Architecture
How Snapchat delivers self-destructing messages while enabling stories, filters, and multi-user features.
Read article →Spotify Music Streaming Architecture
How Spotify serves 100M+ tracks with personalized recommendations to 500M+ users.
Read article →Stock Exchange Matching Engine Architecture
How order matching engines process millions of orders/second with strict fairness + latency guarantees.
Read article →Stripe Payment Platform Architecture
How Stripe abstracts card networks, banks, and payment methods behind a clean API.
Read article →Telegram Architecture
Telegram's proprietary transport and its cloud-chat model that keeps messages accessible from any device.
Read article →TikTok Architecture
The For You Page algorithm and its real-time signal loop.
Read article →Twitter Timeline Generation Architecture
The fan-out patterns that make timelines feel real-time while scaling to hundreds of millions of users.
Read article →Uber Ride Matching Architecture
How Uber matches millions of riders to nearby drivers in seconds via geospatial indexing.
Read article →UPI Architecture
How UPI (Unified Payments Interface) processes 10B+ transactions/month via NPCI + Payment Service Providers.
Read article →Vector Search at Scale
How vector databases (Pinecone, Weaviate, pgvector) find nearest neighbors across billions of embeddings.
Read article →Video Streaming Architecture
How video-on-demand delivers adaptive quality to millions from a mesh of caches.
Read article →Website Hosting Architecture
The complete stack behind a modern static website with HTTPS, CDN, and DNS.
Read article →WeChat Super-App Architecture
How WeChat runs chat, payments, and 3M mini-apps inside a single app with 1.3B users.
Read article →WhatsApp Architecture
How WhatsApp delivers ~100 billion messages/day with end-to-end encryption and offline handling.
Read article →YouTube Architecture
How YouTube ingests, transcodes, stores, and delivers 4B+ hours of video daily.
Read article →Zoom Video Conferencing Architecture
How Zoom achieves low-latency multi-party video via SFU + regional data centers.
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