kimera

Kimera.js

A minimal JavaScript/TypeScript runtime written in Go.

Built on top of QuickJS and esbuild, Kimera provides a fast, lightweight alternative for running JavaScript and TypeScript code.

Quick Start

const asyncSayHello = async (text) => {
  console.log(text);
};

asyncSayHello("Hello World!");

kimera run myScript.js
Hello World!

Installation

go install github.com/UltiRequiem/kimera@latest

Features

Kimera.js provides a lightweight JavaScript/TypeScript runtime with the following capabilities:

1. Interactive REPL

Launch an interactive Read-Eval-Print Loop for testing JavaScript code:

kimera

The REPL supports:

• Multi-line statements
• Variable persistence across commands
• Full JavaScript ES6+ syntax
• Exit using Ctrl+C or Ctrl+D

2. Script Execution

Run JavaScript or TypeScript files directly:

kimera run myScript.js
kimera run myScript.ts

Permission Flags (planned for future use):

kimera run script.js --fs    # Allow filesystem access
kimera run script.js --net   # Allow network access
kimera run script.js --env   # Allow environment variable access

3. TypeScript Support

Native TypeScript support out of the box - no configuration needed. Kimera automatically transpiles TypeScript files using esbuild:

const greet = (name: string): void => {
  console.log(`Hello, ${name}!`);
};

greet("World");

4. Modern JavaScript Features

Full support for modern JavaScript syntax including:

• Async/await
• Arrow functions
• Template literals
• Destructuring
• ES6+ features
• Promises

Example:

const fetchData = async () => {
  return "Data loaded";
};

fetchData().then((data) => console.log(data));

5. Console API

Standard console logging functionality:

console.log("Simple message");
console.log("Multiple", "arguments", "supported");
console.log(`Template literals: ${1 + 1}`);

6. File System API

Built-in file handling through the Kimera global object:

Reading Files

// Read file content as string
const content = Kimera.readFile("path/to/file.txt");
console.log(content);

Writing Files

// Write string content to file
Kimera.writeFile("path/to/output.txt", "Hello World!");

// Write multi-line content
const data = "Line 1\nLine 2\nLine 3";
Kimera.writeFile("output.txt", data);

Error Handling

File operations throw errors for invalid operations:

try {
  const content = Kimera.readFile("nonexistent.txt");
} catch (error) {
  console.log("File not found!");
}

7. Global Objects

Kimera provides the following global objects:

• console - Console logging API
• Kimera - File system and runtime API
• close() - Function to exit the runtime

8. Version Information

Check the installed Kimera version:

kimera version

9. HTTP/Fetch API (Experimental)

Make HTTP requests with the fetch API:

// Make a GET request
const response = fetch("https://api.example.com/data");
console.log("Status: " + response.status);
const data = response.json();

// Make a POST request
const postResponse = fetch("https://api.example.com/data", {
  method: "POST",
  body: JSON.stringify({ key: "value" }),
  headers: {
    "Content-Type": "application/json",
  },
});

CLI Usage

# Run the REPL
kimera

# Run a JavaScript file
kimera run script.js

# Run a TypeScript file
kimera run script.ts

# Check version
kimera version

# Get help
kimera --help

Development

Building from Source

git clone https://github.com/UltiRequiem/kimera.git
cd kimera
go build

Running Tests

go test ./...

Roadmap

• Module system (import/export)
• npm package support
• More Node.js API compatibility
• Better error messages
• Debugger support
• Permission system implementation (--fs, --net, --env flags)

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

Kimera.js is licensed under the MIT License.