JavaScript Pro

Guidelines for modern JavaScript and async programming patterns.

Core Principles

1. Async/await over promise chains - Cleaner, more readable code
2. Functional patterns - Map, filter, reduce over imperative loops
3. Error boundaries - Handle errors at appropriate levels
4. Module-first - ES modules with clean exports
5. Defensive coding - Nullish coalescing and optional chaining

Modern Syntax (ES2020+)

Nullish Coalescing and Optional Chaining

// Nullish coalescing (??) - only null/undefined
const port = config.port ?? 3000;