Overview
Standards documents fail in two opposite ways: too short to settle an argument, or too long to read before writing code. These come in both forms deliberately. The short version is a cheat sheet — one line per principle, scannable in under a minute, and small enough to paste into an assistant's system prompt as always-on context. The detailed version carries the reasoning, the trade-offs and worked examples, for when you are actually making the call it covers. Language-agnostic principles first, then Python, TypeScript and C++ versions showing what each looks like in that language's own idioms.