Just JavaScript!

Faster than VDOM. No Build Step. Use the Platform!

JJ is a lightweight, no-transpilation library for modern web development. What You Write Is What Is Run (WYWIWIR).

⚡ Quick Start

npm i jj

import { JJHE } from 'jj'

JJHE.create('div')
    .addClass('card')
    .setText('Hello World!')
    .on('click', () => console.log('Hi'))
    .appendToBody()

🚀 Why JJ?

• Zero Build – Runs directly in modern browsers
• Native Speed – Direct DOM manipulation, no VDOM overhead
• Web Standards – First-class Web Components support
• Fluent API – Chainable methods for cleaner code

📚 Learn More

👉 Visit the full site with tutorials, examples, and API docs

🤖 AI-Optimized Development

JJ is designed for AI-assisted development. Install the skill for intelligent code suggestions:

npx skills add alexewerlof/jj

Once installed, AI agents (GitHub Copilot, Cursor, Claude Code, Windsurf, etc.) will:

• Follow JJ's patterns and conventions automatically
• Know when to use .ref for native DOM access
• Suggest correct framework translations (React/Vue/jQuery/Svelte → JJ)
• Generate idiomatic, type-safe code

The skill definition (SKILL.md) is also included in the npm package at node_modules/jj/SKILL.md.

✅ Testing

The entire public API is tested thoroghly. Tests live in the test/ folder and mirror the source filenames (e.g., test/JJE.test.ts for src/JJE.ts) while importing the target from ./src/index.js.

Run tests with:

npm test

License

MIT

Made in Sweden 🇸🇪 by Alex Ewerlöf