node-best-practices

When to use

Use this skill whenever you are dealing with Node.js code to obtain domain-specific knowledge for building robust, performant, and maintainable Node.js applications.

TypeScript with Type Stripping

When writing TypeScript for Node.js, use type stripping (Node.js 22.6+) instead of build tools like ts-node or tsx. Type stripping runs TypeScript directly by removing type annotations at runtime without transpilation.

Key requirements for type stripping compatibility:

• Use import type for type-only imports
• Use const objects instead of enums
• Avoid namespaces and parameter properties
• Use .ts extensions in imports

Minimal example — a valid type-stripped TypeScript file:

// greet.ts
import type { IncomingMessage } from 'node:http';

const greet = (name: string): string => `Hello, ${name}!`;
console.log(greet('world'));

Run directly with:

node greet.ts

See rules/typescript.md for complete configuration and examples.

Common Workflows

For multi-step processes, follow these high-level sequences before consulting the relevant rule file:

Graceful shutdown: Register signal handlers (SIGTERM/SIGINT) → stop accepting new work → drain in-flight requests → close external connections (DB, cache) → exit with appropriate code. See rules/graceful-shutdown.md.

Error handling: Define a shared error base class → classify errors (operational vs programmer) → add async boundary handlers (process.on('unhandledRejection')) → propagate typed errors through the call stack → log with context before responding or crashing. See rules/error-handling.md.

Diagnosing flaky tests: Isolate the test with --test-only → check for shared state or timer dependencies → inspect async teardown order → add retry logic as a temporary diagnostic step → fix root cause. See rules/flaky-tests.md.

Profiling a slow path: Reproduce under realistic load → capture a CPU profile with --cpu-prof → identify hot functions → check for stream backpressure or unnecessary serialisation → validate improvement with a benchmark. See rules/profiling.md and rules/performance.md.

How to use

Read individual rule files for detailed explanations and code examples:

• rules/error-handling.md - Error handling patterns in Node.js
• rules/async-patterns.md - Async/await and Promise patterns
• rules/streams.md - Working with Node.js streams
• rules/modules.md - ES Modules and CommonJS patterns
• rules/testing.md - Testing strategies for Node.js applications
• rules/flaky-tests.md - Identifying and diagnosing flaky tests with node:test
• rules/node-modules-exploration.md - Navigating and analyzing node_modules directories
• rules/performance.md - Performance optimization techniques
• rules/caching.md - Caching patterns and libraries
• rules/profiling.md - Profiling and benchmarking tools
• rules/logging.md - Logging and debugging patterns
• rules/environment.md - Environment configuration and secrets management
• rules/graceful-shutdown.md - Graceful shutdown and signal handling
• rules/typescript.md - TypeScript configuration and type stripping in Node.js