Editorial Pillar
System Design
Distributed systems, caching strategies, database internals, and high-scale architecture.
24articles
Python Concurrency: Understanding GIL, Threading, and Multiprocessing from First Principles
In-depth guide to Python Concurrency: Master the GIL, understand Threading vs Multiprocessing, optimize I/O vs CPU workloads, and backend architecture.
DuckDB Is Fast Because It Skips the Part Everyone Forgets
A deep dive into DuckDB internals: why an in-process SQL engine that skips the network beats clusters that cost millions, and what HN thinks about it.
Microsoft open sources pg_durable: Durable workflows inside PostgreSQL
Microsoft open sourced pg_durable, an extension that runs durable execution inside Postgres. HN argues about putting control flow back in the database.
Five Days vs. Five Years: Apple's New Kernel Defense, Cracked
Apple spent five years building MIE on M5 to stop kernel exploits. Calif cracked it in five days with AI, then drove to Apple Park to deliver the report.
Caching & Redis: The 'Sticky Note' Mental Model
Why does Redis make everything faster? A mastery guide to cache invalidation (the hardest problem in CS), eviction strategies, and Redis data types.
CDN: The 'Local Convenience Store' Mental Model
Why does your image load instantly for users in the US but crawls in Vietnam? A mastery guide to CDN Edge Nodes, Cache-Control headers, and cache busting.
Database Indexing: The 'Library Card Catalog' Mental Model
Why does adding an index make a query 100x faster? A mastery guide to B-Trees, compound indexes, covering indexes, and the queries that kill your database.
Task Queues & Message Brokers: Celery, RabbitMQ, and Kafka Untangled
Why does sending an email block your API? A mastery guide to async task queues (Celery/Django-Q), message brokers (RabbitMQ), and event streaming (Kafka).
Observability: Logs vs. Metrics vs. Tracing - The 'Doctor's Kit' Mental Model
Your app is slow. Is it the DB? The queue? The network? A mastery guide to the three pillars of observability and how they work together.
Rate Limiting & Circuit Breaker: The 'Traffic Light & Fuse Box' Mental Model
How do you stop one bad client from taking down your entire API? A mastery guide to rate limiting strategies, circuit breakers, and resilience patterns.
Why Cheap Hardware Won't Make Redis Replace a Core Database
As hardware gets cheaper, why not use Redis as the main database? The short answer: because the limitation isn't speed. It's guarantees and data semantics.
REST vs. GraphQL vs. gRPC: The 'Restaurant Menu' Mental Model
Why does GraphQL exist if REST works fine? A mastery guide to API protocols, when to use each, and how gRPC changes the game for internal services.
Vector Databases & Embeddings: The 'Semantic Atlas' Mental Model
How does Spotify know you'll like this song? A mastery guide to embeddings, cosine similarity, and vector databases (Pinecone, Weaviate, pgvector).
Why Is Production Still Running My Old Code?
Deployed your latest changes but still seeing the ghost of the old version? Let's talk about the aggressive memory of browsers and how to fix it.
Stop Bloating Your Database: The S3 Pointer Pattern
Why 10MB JSON blobs kill your buffer pool, and how to keep MySQL lean with S3 + presigned URLs.
API Certificates: The Mastery Guide to Debugging & The Chain of Trust
Stop guessing with SSLErrors. A mastery-level guide to the Chain of Trust, openssl debugging, and proving exactly whose fault it is.
Authentication vs. Authorization vs. OAuth: The 'ID Card' Mental Model
Stop mixing up 401 and 403. A mastery guide to AuthN (Who you are), AuthZ (What you can do), and the OAuth Valet Key.
Consistent Hashing: The 'Locker Room' Mental Model
How does Cassandra know which server stores your data? Master consistent hashing, virtual nodes, and scaling distributed systems reliably.
Latency vs. Throughput: The 'Water Pipe' Mental Model
Why is your API slow even though your internet is fast? A mastery guide to P99 latency, bandwidth, and finding the bottleneck.
Load Balancer, Reverse Proxy, API Gateway: The Grand Hotel Mental Model
Confused by the 'Traffic Trio'? A mastery-level guide to Load Balancers, Reverse Proxies, and API Gateways - from mental models to Nginx configs.
Monolith vs. Microservices: The 'Mansion vs. Village' Mental Model
Is Microservices mostly hype? A mastery guide to the 'Distributed Monolith', Latency taxes, and knowing when to split.
Partitioning, Bucketing, Sharding, Replication, Edge: The Clean Mental Model
A precise mental model for partitioning, bucketing, sharding, replication, and edge computing - when to use each and why they exist at different layers.
SQL vs. NoSQL: The 'Library vs. Warehouse' Mental Model
Why is MongoDB faster but Postgres safer? A mastery guide to Schema, ACID, and why JSONB might be the only NoSQL you need.
TCP vs. UDP: The 'Registered Mail' Mental Model
Why does video calling glitch but file downloads pause? A mastery guide to the 3-Way Handshake, Head-of-Line Blocking, and why UDP is winning (HTTP/3).