Node Modern

What it does

When your agent uses it

• Refactoring Node.js code — modules
• File and process I/O
• HTTP — on a current Node.js release

Example prompts

• “Node.js”
• “CommonJS”
• “require”
• “/node-modern”

Requirements

• Node.js

Workflow steps

8 steps, taken from the first numbered list in SKILL.md.

1. 1Match the module system. In an ESM package ("type": "module" or .mjs)
2. 2Import built-ins with the node: prefix (node:fs/promises, node:path).
3. 3Give every operation that can wait a deadline: pass an AbortSignal to
4. 4Prefer built-ins over dependencies — global fetch over axios/node-fetch,
5. 5Handle ENOENT by reading inside try/catch and branching on err.code;
6. 6Never block the event loop in a server or CLI hot path: no *Sync fs calls
7. 7Pass arguments to child processes as an array (execFile/spawn), never by
8. 8Every promise is awaited, returned, or explicitly handled; let entry points

What it can do on your machine

Read from SKILL.md and the folder at commit 57f6018. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are typescript).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Node Modern loads about 1.3k tokens when it runs. Until then it costs about 89 tokens; SKILL.md has 404 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~89

When it runs · the whole SKILL.md, loaded when a task matches

~1.3k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from WrongStack/WrongStack at commit 57f6018, republished under its MIT licence (© WrongStack). 404 words, ~1,327 tokens.

name

node-modern

description

Use this skill when writing, reviewing, or refactoring Node.js code — modules, async flow, cancellation, file and process I/O, HTTP — on a current Node.js release. Triggers: user mentions "Node", "Node.js", "ESM", "CommonJS", "require", "import", "fetch", "AbortSignal", "AbortController", "stream", "child_process", "spawn", "fs", "event loop".

version

2.0.0

required-capabilities

filesystem.read, filesystem.write

optional-capabilities

verification.run

import { execFile } from 'node:child_process';
import { randomBytes } from 'node:crypto';
import { readFile, rename, writeFile } from 'node:fs/promises';
import { setTimeout as delay } from 'node:timers/promises';
import { promisify } from 'node:util';

const execFileAsync = promisify(execFile);

// Deadline plus user cancellation.
export async function getJson(url: string, signal?: AbortSignal): Promise<unknown> {
  const deadline = AbortSignal.timeout(10_000);
  const res = await fetch(url, { signal: signal ? AbortSignal.any([signal, deadline]) : deadline });
  if (!res.ok) throw new Error(`GET ${url} failed with ${res.status}`);
  return res.json();
}

// Missing file is an expected outcome, not an exception.
export async function readOptional(path: string): Promise<string | undefined> {
  try {
    return await readFile(path, 'utf8');
  } catch (err) {
    if ((err as NodeJS.ErrnoException).code === 'ENOENT') return undefined;
    throw err;
  }
}

// Atomic replace: readers never observe a half-written file.
export async function writeAtomic(target: string, data: string): Promise<void> {
  const tmp = `${target}.${randomBytes(4).toString('hex')}.tmp`;
  await writeFile(tmp, data);
  await rename(tmp, target);
}

// Cancellable delay — the promise API takes a signal; the global setTimeout does not.
await delay(500, undefined, { signal: AbortSignal.timeout(5_000) });

// Arguments as an array — no shell, no injection.
const { stdout } = await execFileAsync('git', ['log', '--oneline', '-5'], {
  signal: AbortSignal.timeout(15_000),
});

// Partial failure is acceptable: collect every outcome.
const results = await Promise.allSettled(urls.map((url) => getJson(url)));
const failed = results.filter((r) => r.status === 'rejected');

© WrongStack, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 1 other file in packages/core/skills/node-modern of WrongStack/WrongStack.

• SKILL.md
• SKILL.save.md

Open the folder on GitHubat commit 57f6018