nodejs-expert

Node.js gotchas and decision criteria. Covers async pitfalls, Express/NestJS patterns, and common mistakes.

Best use case

nodejs-expert is best used when you need a repeatable AI agent workflow instead of a one-off prompt.

Node.js gotchas and decision criteria. Covers async pitfalls, Express/NestJS patterns, and common mistakes.

Teams using nodejs-expert should expect a more consistent output, faster repeated execution, less prompt rewriting.

When to use this skill

  • You want a reusable workflow that can be run more than once with consistent structure.

When not to use this skill

  • You only need a quick one-off answer and do not need a reusable workflow.
  • You cannot install or maintain the underlying files, dependencies, or repository context.

Installation

Claude Code / Cursor / Codex

$curl -o ~/.claude/skills/nodejs-expert/SKILL.md --create-dirs "https://raw.githubusercontent.com/nguyenthienthanh/aura-frog/main/aura-frog/skills/nodejs-expert/SKILL.md"

Manual Installation

  1. Download SKILL.md from GitHub
  2. Place it in .claude/skills/nodejs-expert/SKILL.md inside your project
  3. Restart your AI agent — it will auto-discover the skill

How nodejs-expert Compares

Feature / Agentnodejs-expertStandard Approach
Platform SupportNot specifiedLimited / Varies
Context Awareness High Baseline
Installation ComplexityUnknownN/A

Frequently Asked Questions

What does this skill do?

Node.js gotchas and decision criteria. Covers async pitfalls, Express/NestJS patterns, and common mistakes.

Where can I find the source code?

You can find the source code on GitHub using the link provided at the top of the page.

SKILL.md Source

> **AI-consumed reference.** Optimized for Claude to read during execution.
> Human-readable explanation: see [docs/architecture/HIERARCHICAL_PLANNING.md](../../../docs/architecture/HIERARCHICAL_PLANNING.md)
> or [docs/getting-started/](../../../docs/getting-started/) depending on topic.


# Node.js Expert — Gotchas & Decisions

Use Context7 for Express/NestJS/Fastify docs.

## Key Decisions

```toon
decisions[4]{choice,use_when}:
  Express vs NestJS vs Fastify,"Express: simple APIs. NestJS: enterprise/DI/decorators. Fastify: high perf"
  Prisma vs TypeORM vs Drizzle,"Prisma: best DX/types. TypeORM: Active Record pattern. Drizzle: SQL-like + lightweight"
  Zod vs Joi vs class-validator,"Zod: TS-first inference. Joi: runtime schemas. class-validator: NestJS decorators"
  JWT vs session,"JWT: stateless/microservices. Session: monolith/server-rendered"
```

## Gotchas

- `forEach` + `async`: does NOT await. Use `for...of` or `Promise.all(items.map(async ...))`
- Express error handler: MUST have 4 params `(err, req, res, next)` — even if unused, or Express ignores it
- Unhandled promise rejection crashes Node 15+ — always catch or use `process.on('unhandledRejection')`
- `asyncHandler` wrapper: wrap Express route handlers to catch async errors → `next(err)`
- `req.body` is `undefined` without `express.json()` middleware — common setup miss
- `process.env.PORT` is string — parse with `parseInt()` or `Number()` before comparison
- NestJS: `@Injectable()` with `@Module({ providers: [...] })` — forgetting module registration = runtime error
- Stream backpressure: always handle `drain` event on writable streams for large data
- `__dirname` not available in ESM — use `import.meta.dirname` (Node 21+) or `fileURLToPath(import.meta.url)`

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