# [Install Polygonjs](/install) / Add Polygonjs to an Existing Project

Since Polygonjs is just an npm module, you can add it to any npm project:

<DocCodeBlock npm="npm add polygonjs-editor" yarn="yarn add polygonjs-editor"></DocCodeBlock>

Then you can start Polygonjs Editor with:

<DocCodeBlock npm="npm run polygonjs-editor" yarn="yarn polygonjs-editor"></DocCodeBlock>

## Using a shorter command

We recommend that you add an alias in the `scripts` section of your `package.json` file, like this:

```json
...
"scripts": {
    ...
    "polygon": "polygonjs-editor",
},
...
```

You'll then be able to start the editor with:

<DocCodeBlock npm="npm run polygon" yarn="yarn polygon"></DocCodeBlock>

## .gitignore

You may also want to add the following lines to your `.gitignore` file:

```txt
public/polygonjs/backup
public/polygonjs/js
public/polygonjs/build
.polygonjs-editor.log
# When more than one person is working on a scene,
# it may be useful to also ignore the editor.json
# to avoid any merge conflict
# public/polygonjs/scenes/[a-z0-9\_]*/editor.json
```

## What's next?

Let's now have a loot at how to <DocRouterLink bang href="/docs/export!" innerText="Export your scene &rarr;"></DocRouterLink>