javascript-pro

Q: What is a Claude Code skill and how does the javascript-pro skill fit in?

A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. javascript-pro is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the Engineering category. Learn more at https://claudskills.com/learn/what-is-skill-md/.

Category: Engineering · Sub-category: languages · Last updated: 2026-06-07

lang:javascript type:review

Writes, debugs, and refactors JavaScript code using modern ES2023+ features, async/await patterns, ESM module systems, and Node.js APIs. Use when building vanilla JavaScript applications, implementing Promise-based async flows, optimising browser or Node.js performance, working with Web Workers or Fetch API, or reviewing .js/.mjs/.cjs files for correctness and best practices.

What this skill does

javascript-pro is a community-contributed Claude Code skill in the languages sub-category. It ships as a SKILL.md file that Claude Code auto-discovers under ~/.claude/skills/cs-javascript-pro/ and loads when your prompt matches the skill's trigger.

When to invoke it: Use when building vanilla JavaScript applications, implementing Promise-based async flows, optimising browser or Node.js performance, working with Web Workers or Fetch API, or reviewing .

Who uses this skill

The javascript-pro Claude Code skill is built for software engineers, backend developers, full-stack teams, and technical leads building and maintaining production systems. It's part of ClaudSkills (also referred to as Claude Skills or Claude Code Skills) — the open community-curated registry of 97,000+ SKILL.md files for Anthropic's Claude Code agent and the wider Claude ecosystem (Claude API, Claude Agent SDK).

How to install

Free

Manual install (2 steps)

mkdir -p ~/.claude/skills/cs-javascript-pro
curl -L https://claudskills.com/skills/cs-javascript-pro/SKILL.md \
  -o ~/.claude/skills/cs-javascript-pro/SKILL.md

Or just download SKILL.md directly and drop it into ~/.claude/skills/cs-javascript-pro/. Claude Code auto-discovers it on next session.

Skills live at ~/.claude/skills/cs-javascript-pro/SKILL.md on macOS/Linux, or %USERPROFILE%\.claude\skills\cs-javascript-pro\SKILL.md on Windows. See the full install guide for step-by-step instructions.

📱 Install from your phone or desktop Telegram

Open @claudskills_bot on Telegram, tap Open Desktop App, and the desktop app installs this skill for you. Or share the bot link with a colleague — they get the same one-tap install. Learn more →

Pro

One-click install via the desktop app

The ClaudSkills desktop app installs any skill directly into ~/.claude/skills/ with one click — no terminal required. Pro starts at $9/mo or $149 lifetime.

Pro

For the full experience including quality scoring and one-click install features for each skill — upgrade to Pro.

See pricing → Download desktop app

Frequently asked questions

How do I install the javascript-pro Claude Code skill?

Install via the ClaudSkills desktop app (one click) or copy SKILL.md from the source repository to ~/.claude/skills/cs-javascript-pro/SKILL.md and restart Claude Code. Both flows are detailed at claudskills.com/install/.

What does the javascript-pro skill do?

Is this skill free to install?

Yes. ClaudSkills is an open registry — every skill keeps its source repository's license, and manual install via copy is free. ClaudSkills Pro ($9/mo, $79/yr, or $149 one-time) adds one-click install via the desktop app and a multi-signal Quality Score.

When should I use the javascript-pro skill?

Use javascript-pro when your Claude Code task falls under the Engineering category — specifically in the languages area. Claude Code auto-discovers installed skills and invokes the right one based on the task description, so you can also ask Claude directly (e.g. "use javascript-pro" or describe the task and let Claude pick). Browse related skills at /category/engineering/.

What is a Claude Code skill and how does the javascript-pro skill fit in?

A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. javascript-pro is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the Engineering category. Learn more at /learn/what-is-a-claude-skill/.

Attribution & license

Source: https://github.com/ankurCES/blumi-cli/blob/HEAD/crates/blumi-skills/bundled/skills/cs-javascript-pro/SKILL.md
License: Apache-2.0
Author: ankurCES
Website: https://github.com/ankurCES/blumi-cli/wiki

Cite this skill

If you reference this skill in a blog post, paper, or documentation, you can cite it as:

APA

ankurCES. (2026). javascript-pro [Claude Code skill]. ClaudSkills. https://claudskills.com/skills/cs-javascript-pro/

BibTeX

@misc{cs-javascript-pro-2026,
  author    = {ankurCES},
  title     = {javascript-pro [Claude Code skill]},
  year      = {2026},
  publisher = {ClaudSkills},
  url       = {https://claudskills.com/skills/cs-javascript-pro/}
}

Embed this skill

Promote, attribute, or link this skill from your own README, blog post, or documentation. All three snippets are free to use — no sign-up, no API key. More distribution surfaces →

Badge

[![ClaudSkills](https://claudskills.com/badge/cs-javascript-pro.svg)](https://claudskills.com/skills/cs-javascript-pro/?utm_source=badge&utm_medium=readme&utm_campaign=skill_badge)

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Part of ClaudSkills — the open registry for Claude Skills & Claude Code Skills. · What's New · Install guide · About · llms.txt

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