Node.js

Async I/O, process management, backend services with Node.js runtime.

Examples use TypeScript. For JavaScript, remove type annotations (: string, interface, <T>, Promise<T>) — patterns apply identically.

When to Use

• Building backend services or REST/GraphQL APIs
• Writing CLI tools, build scripts, or automation tasks
• Managing long-running processes (workers, daemons)
• Handling file I/O, streams, or network operations
• Developing real-time applications (WebSockets, SSE)

Don't use for:

• CPU-intensive tasks (worker threads/separate processes)
• Browser code (javascript/typescript skills)
• Framework patterns (express, nest, hono skills)