Modern JavaScript Patterns

Comprehensive guide for mastering modern JavaScript (ES6+) features, functional programming patterns, and best practices for writing clean, maintainable, and performant code.

When to Use This Skill

• Refactoring legacy JavaScript to modern syntax
• Implementing functional programming patterns
• Optimizing JavaScript performance
• Writing maintainable and readable code
• Working with asynchronous operations
• Building modern web applications
• Migrating from callbacks to Promises/async-await
• Implementing data transformation pipelines

Detailed patterns and worked examples

Detailed pattern documentation lives in references/details.md. Read that file when the navigation tier above is insufficient.

Best Practices

1. Use const by default: Only use let when reassignment is needed
2. Prefer arrow functions: Especially for callbacks
3. Use template literals: Instead of string concatenation
4. Destructure objects and arrays: For cleaner code
5. Use async/await: Instead of Promise chains
6. Avoid mutating data: Use spread operator and array methods
7. Use optional chaining: Prevent "Cannot read property of undefined"
8. Use nullish coalescing: For default values
9. Prefer array methods: Over traditional loops
10. Use modules: For better code organization
11. Write pure functions: Easier to test and reason about
12. Use meaningful variable names: Self-documenting code
13. Keep functions small: Single responsibility principle
14. Handle errors properly: Use try/catch with async/await
15. Use strict mode: 'use strict' for better error catching

For common pitfalls (this binding, promise anti-patterns, memory leaks), see references/advanced-patterns.md.