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modern-javascript-patterns skill

by wshobson·wshobson/agents·40k stars·MIT

Master ES6+ features including async/await, destructuring, spread operators, arrow functions, promises, modules, iterators, generators, and functional programming patterns for writing clean, efficient JavaScript code. Use when refactoring legacy code, implementing modern patterns, or optimizing JavaScript applications.

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Install the modern-javascript-patterns skill

A skill is a folder. Copy it into your agent's skills folder and the agent loads it when the task matches its description. 

git clone --depth 1 https://github.com/wshobson/agents.git /tmp/agents
mkdir -p ~/.claude/skills
cp -r /tmp/agents/plugins/javascript-typescript/skills/modern-javascript-patterns ~/.claude/skills/modern-javascript-patterns
available in every project

In the Claude apps, zip the folder and upload it from the Skills settings. The folder on GitHub

The instructions your agent would load

SKILL.md as published, without the frontmatter. Read it on GitHub

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

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

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