javascript-language
Modern JavaScript (ES2022+) patterns for clean, maintainable code. Use when working with modern JavaScript features like optional chaining, nullish coalescing, or ESM. (triggers: **/*.js, **/*.mjs, **/*.cjs, const, let, arrow, async, await, promise, destructuring, spread, class)
Best use case
javascript-language is best used when you need a repeatable AI agent workflow instead of a one-off prompt.
Modern JavaScript (ES2022+) patterns for clean, maintainable code. Use when working with modern JavaScript features like optional chaining, nullish coalescing, or ESM. (triggers: **/*.js, **/*.mjs, **/*.cjs, const, let, arrow, async, await, promise, destructuring, spread, class)
Teams using javascript-language 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
Manual Installation
- Download SKILL.md from GitHub
- Place it in
.claude/skills/javascript-language/SKILL.mdinside your project - Restart your AI agent — it will auto-discover the skill
How javascript-language Compares
| Feature / Agent | javascript-language | Standard Approach |
|---|---|---|
| Platform Support | Not specified | Limited / Varies |
| Context Awareness | High | Baseline |
| Installation Complexity | Unknown | N/A |
Frequently Asked Questions
What does this skill do?
Modern JavaScript (ES2022+) patterns for clean, maintainable code. Use when working with modern JavaScript features like optional chaining, nullish coalescing, or ESM. (triggers: **/*.js, **/*.mjs, **/*.cjs, const, let, arrow, async, await, promise, destructuring, spread, class)
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
# JavaScript Language Patterns
## **Priority: P0 (CRITICAL)**
## Implementation Guidelines
- **Variables**: const default. let if needed. No var — block scope only.
- **Functionality**: Use **`Arrow Functions`** for callbacks/inlines; **`Function Declaration`** for core logic.
- **Async Logic**: Use async/await with try/catch and Promise.all() for parallel operations. ESM import/export only. No Callbacks — promisify everything.
- **Modern Syntax**: Use Destructuring, Spread (...), Optional Chain ?. and Nullish ?? coalescing.
- **String Handling**: Use **`Template Literals`** (backticks) for interpolation and multi-line strings.
- **Data Collections**: Prefer **`map`**, **`filter`**, and **`reduce`** over imperative `for` loops.
- **Modules**: Standardize on ESM import/export; use Named Exports over Default.
- **Encapsulation**: Leverage **`#private`** class fields for encapsulation.
- **Error States**: Throw **`new Error()`** with descriptive messages; never throw strings.
## Anti-Patterns
- No var — Block scope only.
- **No `==`**: Strict `===`.
- **No `new Object()`**: Use literals `{}`.
- No Callbacks: Promisify everything.
- **No Mutation**: Immutability first.
## Code & Reference
See [references/REFERENCE.md](references/REFERENCE.md) for modern syntax, async patterns, private fields, and functional programming examples.
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