> For the complete documentation index, see [llms.txt](https://db.coolstone.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://db.coolstone.dev/key-features.md).

# Key Features

### Local & Unlimited

Since Dubnium is locally stored, the only limit to the amount of data stored is what **you** want! You also don't have to worry about any outages on our end or need any internet connection to use Dubnium¹!

## Customizable

Is Dubnium missing something you need? Extend it!

<pre class="language-javascript" data-line-numbers><code class="lang-javascript"><strong>const Dubnium = require("dubnium")
</strong>class Dubnium2 extends Dubnium {

constructor(dirPath, ext){
super(dirPath,ext)
}

printPath(tag) => {
console.log(this.find(tag))
}
}

new Dubnium2('dir','json').printPath('tag')
</code></pre>

### Small

Dubnium is approximately 35 **kB**, while [Mongoose](https://www.npmjs.com/package/mongoose) is over 2 **MB**.

### Supports any file type

You can use any file type supported by Node.js!

### Multiple databases in *one* project

Dubnium allows you to have as many databases as you need!

### Keep track of versions

Dubnium can also record versions of Records automatically. [Learn more](/3/api/versioning.md)

### Tons of other features

Overwrite, tag/content searching, renamable Records, CLI, powerful deletion methods, [browser](https://db.coolstone.dev/browser/) support, middleware, and more!

### Private

**Nobody** but the people that have access to the directory you created can **ever** see a Record and data never leaves the device it was created on.

### ECMAScript (ESM) & Commonjs supported

Dubnium [v2](https://db.coolstone.dev/2/) and [v1](https://db.coolstone.dev/1/) support Commonjs & ECMAScript modules! Dubnium v0 is ECMAScript only, however, the [Dubnium Archive](https://github.com/coolstone-tech/dubnium-archive) has a Commonjs version.

### Free & Open-sourced

Dubnium is free to use for personal & commercial use. It is also open-sourced and licensed under the MIT license.

### Browser Support

Want to use a similar API on your browser²? You can! Dubnium for browser uses `localStorage` (or `sessionStorage`) to store data. Check out[ the docs](https://db.coolstone.dev/browser/) to get started!

### Updates

Dubnium is actively being developed and new features are added often. If you have an idea, please tell us!

1: After installing

2: Some methods may not be available due to browser limitations.