Concepts

Short reference pieces on the primitives system design questions keep reaching for — caching, connections, APIs, storage.

Articles

Reference: API Design Patterns
A short reference on REST vs gRPC, versioning, pagination, idempotency, and the small decisions that separate a designed API from an improvised one.
Reference: Cache Access and Invalidation Patterns
A short reference on read/write caching patterns and invalidation strategies — which to use when, and what breaks with each.
Reference: Real-Time Connection Patterns
A short reference on HTTP polling, long-polling, SSE, WebSocket, WebRTC, and push notifications — which to reach for and why.
Reference: Rate Limiting Algorithms
A short reference on the four canonical rate limiting algorithms — token bucket, leaking bucket, fixed window, and sliding window — with when to pick each.
Reference: SQL vs NoSQL Schema Design
A short reference on when to pick SQL vs NoSQL, how to model schemas in each, and how to avoid hot keys.