Claude-Code-Workflow/.claude/tech-stack-templates/javascript-dev.md

name, description

name	description
javascript-dev	JavaScript and Node.js core development principles and essential practices

JavaScript Development Guidelines

You are now operating under JavaScript/Node.js core development principles. Focus on essential practices without dictating project structure.

Core Language Principles

Naming Conventions

• Variables/Functions: camelCase (getUserData, isValid)
• Constants: SCREAMING_SNAKE_CASE (API_ENDPOINT, MAX_RETRIES)
• Classes: PascalCase (UserService, ApiClient)

Essential Function Guidelines

• Pure Functions: Prefer functions that don't mutate inputs
• Async/Await: Use instead of Promises for better readability
• Error Handling: Always handle errors explicitly, never silently fail

// Core principle: Clear error handling
async function fetchData(id) {
  try {
    const response = await api.get(`/data/${id}`);
    return response.data;
  } catch (error) {
    throw new DataFetchError(`Failed to fetch data for ${id}: ${error.message}`);
  }
}

Essential Testing Practices

• Test Names: Describe behavior clearly (should return user when ID exists)
• Arrange-Act-Assert: Structure tests consistently
• Mock External Dependencies: Isolate units under test
• Test Edge Cases: Include error conditions and boundary values

Code Quality Essentials

• Consistent Formatting: Use automated formatting (Prettier)
• Linting: Catch common errors early (ESLint)
• Type Safety: Consider TypeScript for larger projects
• Input Validation: Validate all external inputs

Security Core Principles

• Input Sanitization: Never trust user input
• Environment Variables: Keep secrets out of code
• Dependency Management: Regularly audit and update packages
• Error Messages: Don't expose internal details to users

Performance Guidelines

• Avoid Premature Optimization: Write clear code first
• Use Modern Array Methods: map, filter, reduce over manual loops
• Template Literals: For string formatting over concatenation
• Object Destructuring: For cleaner variable extraction

Apply these core JavaScript principles to ensure clean, maintainable, and secure code without imposing specific project structures or tool choices.