# What Frameworks Are Compatible with ag-kit: Node.js, Next.js, and Antigravity Runtime Guide

> Discover ag-kit compatibility with Node.js, Next.js, and Antigravity. Learn about language-agnostic JSON contracts for any JavaScript-compatible environment.

- Repository: [Vũ Đỗ/ag-kit](https://github.com/vudovn/ag-kit)
- Tags: compatibility-guide
- Published: 2026-07-29

---

**ag-kit supports Node.js ≥18 (ESM), Next.js 16 with React 19, and the Antigravity runtime, while providing language-agnostic JSON contracts that work in any environment capable of reading JavaScript and JSON.**

The ag-kit repository by vudovn provides a language-agnostic engineering kit designed for modern development stacks. Understanding what frameworks are compatible with ag-kit helps developers integrate its CLI tools, runtime contracts, and documentation components into existing workflows.

## Node.js and ESM Requirements

### CLI Package Architecture

The `@vudovn/ag-kit` CLI package requires **Node.js version 18 or higher** with ES Module (ESM) support. As defined in [`cli/package.json`](https://github.com/vudovn/ag-kit/blob/main/cli/package.json), the entry point resides at [`cli/bin/index.js`](https://github.com/vudovn/ag-kit/blob/main/cli/bin/index.js), enabling installation via npm and execution through `npx` or direct ES module imports.

### Managed Tree API

Pure JavaScript utilities like the `ManagedTree` class in [`cli/lib/managed-tree.js`](https://github.com/vudovn/ag-kit/blob/main/cli/lib/managed-tree.js) function across any Node environment supporting ESM. This module handles component tree management without external framework dependencies.

```javascript
// Importing the managed-tree API in a Node.js project
import { ManagedTree } from '@vudovn/ag-kit/cli/lib/managed-tree.js';

const tree = new ManagedTree('.');
console.log(tree.listComponents());

```

## Frontend Framework Integration

### Next.js 16 and React 19

The documentation website located in the `web/` directory runs on **Next.js 16** with **React 19** and **Tailwind CSS 4**. The configuration in [`web/next.config.ts`](https://github.com/vudovn/ag-kit/blob/main/web/next.config.ts) establishes a standard Next.js application structure, making the docs site compatible with any React-based hosting environment.

### Tailwind CSS 4 Styling

The frontend utilizes Tailwind CSS 4 for styling, configured alongside the Next.js application. This setup allows components to be imported into existing Next.js projects or adapted for other React frameworks.

```bash

# Clone and run the documentation site

git clone https://github.com/vudovn/ag-kit.git
cd ag-kit/web
npm ci               # Installs Next.js 16, React 19, Tailwind 4

npm run dev          # Launches at http://localhost:3000

```

```tsx
// Example of importing documentation components
import { MyComponent } from '../../components/MyComponent';

export default function Page() {
  return (
    <section className="prose">
      <MyComponent />
    </section>
  );
}

```

## Antigravity Runtime Compatibility

### Contract Execution Environment

The core Antigravity runtime layer consumes configuration files from the `.agents/` directory, specifically [`manifest.json`](https://github.com/vudovn/ag-kit/blob/main/manifest.json) and [`antigravity.json`](https://github.com/vudovn/ag-kit/blob/main/antigravity.json). This runtime is framework-agnostic—any environment capable of executing the Antigravity runtime, including custom servers or cloud functions, can load and execute ag-kit contracts.

```javascript
// Consuming the Antigravity contract
import manifest from '@vudovn/ag-kit/.agents/manifest.json';
import antigravity from '@vudovn/ag-kit/.agents/antigravity.json';

// Runtime initialization (implementation-specific)
const runtime = new AntigravityRuntime({ 
  manifest, 
  config: antigravity 
});
runtime.execute('my-workflow');

```

## Universal JSON Catalogs

The service catalogs stored in `web/src/services/` (such as [`agents.json`](https://github.com/vudovn/ag-kit/blob/main/agents.json)) consist of plain JSON files. These artifacts can be consumed by browsers, Node.js applications, or any programming language capable of parsing JSON, making ag-kit truly polyglot across diverse technology stacks.

## Summary

- **ag-kit requires Node.js ≥18** with ESM support for CLI operations and library consumption.
- The documentation site runs on **Next.js 16**, **React 19**, and **Tailwind CSS 4**, allowing integration with React-based projects.
- The **Antigravity runtime** executes contracts framework-agnostically in any environment that can process the JSON configuration files.
- **JSON catalogs** in `web/src/services/` work universally across languages and platforms.
- Key integration files include [`cli/package.json`](https://github.com/vudovn/ag-kit/blob/main/cli/package.json), [`web/next.config.ts`](https://github.com/vudovn/ag-kit/blob/main/web/next.config.ts), and [`.agents/antigravity.json`](https://github.com/vudovn/ag-kit/blob/main/.agents/antigravity.json).

## Frequently Asked Questions

### Does ag-kit require a specific Node.js version?

Yes, ag-kit requires **Node.js version 18 or higher**. The CLI package (`@vudovn/ag-kit`) is built as an ES Module (ESM) and specifies this requirement in [`cli/package.json`](https://github.com/vudovn/ag-kit/blob/main/cli/package.json). Older versions may lack the necessary ESM support and modern JavaScript features used in the [`cli/lib/managed-tree.js`](https://github.com/vudovn/ag-kit/blob/main/cli/lib/managed-tree.js) implementation.

### Can I integrate ag-kit with frontend frameworks other than Next.js?

While the official documentation site uses Next.js 16, ag-kit's core artifacts—including the JSON catalogs in `web/src/services/` and the Antigravity contracts—are framework-agnostic. You can consume these resources in React, Vue, Angular, or vanilla JavaScript applications as long as the environment supports JSON parsing and JavaScript execution.

### What is the Antigravity runtime in ag-kit?

The Antigravity runtime is the execution layer that consumes the [`.agents/antigravity.json`](https://github.com/vudovn/ag-kit/blob/main/.agents/antigravity.json) contract and [`manifest.json`](https://github.com/vudovn/ag-kit/blob/main/manifest.json) files. According to the source code analysis, it reads these configuration files to execute workflows and manage agent behaviors. It operates as a framework-agnostic layer that can run on custom servers, cloud functions, or any environment capable of loading the contract files.

### How do I consume ag-kit JSON catalogs in my application?

Import the catalog files directly from `web/src/services/` (e.g., [`agents.json`](https://github.com/vudovn/ag-kit/blob/main/agents.json), [`skills.json`](https://github.com/vudovn/ag-kit/blob/main/skills.json)). These files contain plain JSON data that can be parsed by any programming language. In JavaScript or TypeScript projects, use standard JSON imports or fetch requests to load the data into your application state.