JavaScript Pro
Jeffallan/claude-skills
Writes and reviews modern JavaScript: ES2023+ syntax, async/await, ESM modules, Node.js and browser APIs, with linting, leak checks and Jest tests.
Covers ES6+ syntax and functional patterns for refactoring older JavaScript: async/await, destructuring, spread, modules, generators and data pipelines.
Install Modern JavaScript Patterns
$ npx skills add wshobson/agents --skill modern-javascript-patterns -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install wshobson/agents modern-javascript-patterns --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/wshobson/agents.git skills-src && mkdir -p .claude/skills && cp -r skills-src/plugins/javascript-typescript/skills/modern-javascript-patterns .claude/skills/modern-javascript-patterns && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "modern-javascript-patterns" agent skill from https://github.com/wshobson/agents/tree/main/plugins/javascript-typescript/skills/modern-javascript-patterns into .claude/skills/modern-javascript-patterns/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "modern-javascript-patterns", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/wshobson/agents/tree/main/plugins/javascript-typescript/skills/modern-javascript-patternsType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add wshobson/agents --skill modern-javascript-patterns -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install wshobson/agents modern-javascript-patterns --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/wshobson/agents.git skills-src && mkdir -p .agents/skills && cp -r skills-src/plugins/javascript-typescript/skills/modern-javascript-patterns .agents/skills/modern-javascript-patterns && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "modern-javascript-patterns" agent skill from https://github.com/wshobson/agents/tree/main/plugins/javascript-typescript/skills/modern-javascript-patterns into .agents/skills/modern-javascript-patterns/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "modern-javascript-patterns", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add wshobson/agents --skill modern-javascript-patterns -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install wshobson/agents modern-javascript-patterns --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/wshobson/agents.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/plugins/javascript-typescript/skills/modern-javascript-patterns .cursor/skills/modern-javascript-patterns && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "modern-javascript-patterns" agent skill from https://github.com/wshobson/agents/tree/main/plugins/javascript-typescript/skills/modern-javascript-patterns into .cursor/skills/modern-javascript-patterns/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "modern-javascript-patterns", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/wshobson/agents.git --path plugins/javascript-typescript/skills/modern-javascript-patterns--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add wshobson/agents --skill modern-javascript-patterns -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install wshobson/agents modern-javascript-patterns --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/wshobson/agents.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/plugins/javascript-typescript/skills/modern-javascript-patterns .gemini/skills/modern-javascript-patterns && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "modern-javascript-patterns" agent skill from https://github.com/wshobson/agents/tree/main/plugins/javascript-typescript/skills/modern-javascript-patterns into .gemini/skills/modern-javascript-patterns/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "modern-javascript-patterns", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install wshobson/agents modern-javascript-patternsInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add wshobson/agents --skill modern-javascript-patterns -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/wshobson/agents.git skills-src && mkdir -p .github/skills && cp -r skills-src/plugins/javascript-typescript/skills/modern-javascript-patterns .github/skills/modern-javascript-patterns && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "modern-javascript-patterns" agent skill from https://github.com/wshobson/agents/tree/main/plugins/javascript-typescript/skills/modern-javascript-patterns into .github/skills/modern-javascript-patterns/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "modern-javascript-patterns", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add wshobson/agents --skill modern-javascript-patterns -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install wshobson/agents modern-javascript-patterns --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/wshobson/agents.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/plugins/javascript-typescript/skills/modern-javascript-patterns .opencode/skills/modern-javascript-patterns && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "modern-javascript-patterns" agent skill from https://github.com/wshobson/agents/tree/main/plugins/javascript-typescript/skills/modern-javascript-patterns into .opencode/skills/modern-javascript-patterns/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "modern-javascript-patterns", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
modern-javascript-patterns- GitHub stars
- 40k
- Used in
- 11 other repos
- Token cost
- ~548 tokens
- SKILL.md length
- 223 words
- Files
- 3 (incl. references)
- Skills in repo
- 142
- Repo updated
- First seen
- Licence
- MIT
At a glance
Covers ES6+ syntax and functional patterns for refactoring older JavaScript: async/await, destructuring, spread, modules, generators and data pipelines.
- Works in 12 steps: Use const by default: Only use let when… → Prefer arrow functions: Especially for… → Use template literals: Instead of string… → …
- Refactoring legacy JavaScript to ES6+ syntax
- SKILL.md covers When to Use This Skill, Detailed patterns and worked… and Best Practices
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
This skill steers the agent toward current JavaScript idioms when it writes or rewrites code. Its checklist covers const by default, arrow functions for callbacks, template literals, destructuring, optional chaining, nullish coalescing, array methods in place of loops, modules, pure functions and strict mode.
It suits migrations such as turning callback code into promises or async/await, and building data transformation pipelines in a functional style. Pitfalls like this binding, promise anti-patterns and memory leaks are covered in references/advanced-patterns.md, and further worked patterns are in references/details.md.
When your agent uses it
- Refactoring legacy JavaScript to ES6+ syntax
- Converting callback-based code to promises or async/await
- Writing data transformation pipelines in a functional style
- Reviewing JavaScript for common pitfalls such as this binding
Example prompts
- “Rewrite this callback-heavy Node module using async/await.”
- “Modernize utils.js: replace var with const and let, and use destructuring and optional chaining.”
- “Turn these nested for loops into array method chains.”
Workflow steps
12 steps, taken from the first numbered list in SKILL.md.
- Use const by default: Only use let when reassignment is needed
- Prefer arrow functions: Especially for callbacks
- Use template literals: Instead of string concatenation
- Destructure objects and arrays: For cleaner code
- Use async/await: Instead of Promise chains
- Avoid mutating data: Use spread operator and array methods
- Use optional chaining: Prevent "Cannot read property of undefined"
- Use nullish coalescing: For default values
- Prefer array methods: Over traditional loops
- Use modules: For better code organization
- Write pure functions: Easier to test and reason about
- Use meaningful variable names: Self-documenting code
What it can do on your machine
Read from SKILL.md and the folder at commit 46891e7. 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.
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
Modern JavaScript Patterns loads about 548 tokens when it runs, and up to ~5.7k if it reads all its reference files. Until then it costs about 87 tokens; SKILL.md has 223 words of instructions outside code blocks.
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
Auto-check passed
The automated check found no risky patterns in SKILL.md.
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 wshobson/agents at commit 46891e7, republished under its MIT licence (© wshobson). 223 words, ~548 tokens.
Download SKILL.mdSave it as
.claude/skills/modern-javascript-patterns/SKILL.md (or your agent's skills folder). This skill also uses 2 other files; get the full folder from GitHub.- name
- modern-javascript-patterns
- description
- Master ES6+ features including async/await, destructuring, spread operators, arrow functions, promises, modules, iterators, generators, and functional programming patterns for writing clean, efficient JavaScript code. Use when refactoring legacy code, implementing modern patterns, or optimizing JavaScript applications.
Modern JavaScript Patterns
Comprehensive guide for mastering modern JavaScript (ES6+) features, functional programming patterns, and best practices for writing clean, maintainable, and performant code.
When to Use This Skill
- Refactoring legacy JavaScript to modern syntax
- Implementing functional programming patterns
- Optimizing JavaScript performance
- Writing maintainable and readable code
- Working with asynchronous operations
- Building modern web applications
- Migrating from callbacks to Promises/async-await
- Implementing data transformation pipelines
Detailed patterns and worked examples
Detailed pattern documentation lives in references/details.md. Read that file when the navigation tier above is insufficient.
Best Practices
- Use const by default: Only use let when reassignment is needed
- Prefer arrow functions: Especially for callbacks
- Use template literals: Instead of string concatenation
- Destructure objects and arrays: For cleaner code
- Use async/await: Instead of Promise chains
- Avoid mutating data: Use spread operator and array methods
- Use optional chaining: Prevent "Cannot read property of undefined"
- Use nullish coalescing: For default values
- Prefer array methods: Over traditional loops
- Use modules: For better code organization
- Write pure functions: Easier to test and reason about
- Use meaningful variable names: Self-documenting code
- Keep functions small: Single responsibility principle
- Handle errors properly: Use try/catch with async/await
- Use strict mode:
'use strict'for better error catching
For common pitfalls (this binding, promise anti-patterns, memory leaks), see references/advanced-patterns.md.
© wshobson, 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 2 other files (references) in plugins/javascript-typescript/skills/modern-javascript-patterns of wshobson/agents.
- SKILL.md
- references/advanced-patterns.md
- references/details.md
Open the folder on GitHubat commit 46891e7
Used in 11 other repositories
We found 26 copies of this SKILL.md (exact, near-identical or edited) in other folders, from 11 other GitHub owners. This page covers the copy in wshobson/agents, which our catalogue first saw on October 7, 2026.
- HermeticOrmus/LibreUIUX-Claude-Codeplugins/javascript-typescript/skills/modern-javascript-patterns
- Microck/ordinary-claude-skillsskills_all/modern-javascript-patternsskills_categorized/frontend/modern-javascript-patterns+4 more
- aiskillstore/marketplaceskills/sickn33/modern-javascript-patternsskills/wshobson/modern-javascript-patterns
- sickn33/agentic-awesome-skillsskills/modern-javascript-patternsplugins/agentic-awesome-skills/skills/modern-javascript-patterns+1 more
- rmyndharis/antigravity-skillsskills/modern-javascript-patterns
- agent-skills-hub/agent-skills-hubskills/modern-javascript-patterns
- lingxling/awesome-skills-cnantigravity-awesome-skills/skills/modern-javascript-patternsantigravity-awesome-skills/plugins/agentic-awesome-skills/skills/modern-javascript-patterns+1 more
- benjaminasterA/antigravity-awesome-skillsskills/modern-javascript-patterns
- LeoYeAI/openclaw-master-skillsskills/modern-javascript-patterns
- henryalouf/ruflow.agents/skills/modern-javascript-patterns.agents/skills/antigravity-awesome-skills/skills/modern-javascript-patterns+4 more
- infometa/workbuddyskillsplugins/codebuddy-plugins-official/external_plugins/javascript-typescript/skills/modern-javascript-patterns
Compare with similar skills
Modern JavaScript Patterns next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Modern JavaScript Patterns this skillwshobson/agents | 40k | 11 repos | ~548 | Automated safety check: Pass | MIT | |
| JavaScript ProJeffallan/claude-skills | 12k | — | ~1.2k | Automated safety check: Pass | MIT | |
| Code Refactoring Workflowluongnv89/claude-howto | 42k | — | ~3.1k | Automated safety check: Pass | MIT | |
| DRY Refactoring With jscpdkucherenko/jscpd | 6.3k | — | ~2.1k | Automated safety check: Pass | MIT | |
| jscpd Duplicate Code Detectorkucherenko/jscpd | 6.3k | — | ~4.6k | Automated safety check: Pass | MIT | |
| Fowler-Style Refactoringlhfer/claude-howto-zh-cn | 2.3k | — | ~156 | Automated safety check: Pass | MIT |
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Related
Works with
Categories
Questions about Modern JavaScript Patterns
What does Modern JavaScript Patterns do?
Covers ES6+ syntax and functional patterns for refactoring older JavaScript: async/await, destructuring, spread, modules, generators and data pipelines. This skill steers the agent toward current JavaScript idioms when it writes or rewrites code. Its checklist covers const by default, arrow functions for callbacks, template literals, destructuring, optional chaining, nullish coalescing, array methods in place of loops, modules, pure functions and strict mode.
When should I use Modern JavaScript Patterns?
Modern JavaScript Patterns fits situations like: refactoring legacy JavaScript to ES6+ syntax; converting callback-based code to promises or async/await; writing data transformation pipelines in a functional style; reviewing JavaScript for common pitfalls such as this binding.
How do I install Modern JavaScript Patterns in Claude Code?
Run `npx skills add wshobson/agents --skill modern-javascript-patterns -a claude-code`. Or copy the skill folder (plugins/javascript-typescript/skills/modern-javascript-patterns in wshobson/agents) into .claude/skills/modern-javascript-patterns in your project. Claude Code loads it when a task matches its description.
How do I install Modern JavaScript Patterns in Codex?
Run `npx skills add wshobson/agents --skill modern-javascript-patterns -a codex`. Or copy the skill folder (plugins/javascript-typescript/skills/modern-javascript-patterns in wshobson/agents) into .agents/skills/modern-javascript-patterns in your project. Codex loads it when a task matches its description.
Can I use Modern JavaScript Patterns in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add wshobson/agents --skill modern-javascript-patterns -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/modern-javascript-patterns, .gemini/skills/modern-javascript-patterns, .github/skills/modern-javascript-patterns and .opencode/skills/modern-javascript-patterns in your project.
What does Modern JavaScript Patterns need to run?
SKILL.md names no scripts, command-line tools or credentials: Modern JavaScript Patterns is instructions for the agent only.
Does Modern JavaScript Patterns access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Modern JavaScript Patterns safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Modern JavaScript Patterns use?
Modern JavaScript Patterns is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Modern JavaScript Patterns use?
About 548 tokens (SKILL.md is roughly 2.2k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 5.1k tokens, read only when the agent opens those files.
What are the alternatives to Modern JavaScript Patterns?
Skills that share tags, products or a category with Modern JavaScript Patterns: JavaScript Pro (Jeffallan/claude-skills, 12k stars), Code Refactoring Workflow (luongnv89/claude-howto, 42k stars), DRY Refactoring With jscpd (kucherenko/jscpd, 6.3k stars) and jscpd Duplicate Code Detector (kucherenko/jscpd, 6.3k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Modern JavaScript Patterns?
wshobson (a GitHub user) maintains it in wshobson/agents, which has 40,254 GitHub stars. The repository holds 142 skills in this directory. The repository was last updated on October 5, 2026.
Source: wshobson/agents on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.