# How to test an npm package locally

> Learn how to test your own npm package locally before publishing, using npm link to create a symlink and require it from another project as usual.

Author: Flavio Copes | Published: 2020-04-25 | Canonical: https://flaviocopes.com/npm-local-package/

If you want to develop your own [npm](https://flaviocopes.com/npm/) package, you first have to test it locally.

I had this need with a project that I wanted to modularize.

I had a package I called, as an example, `flaviocopes-common-database`.

I prepended `flaviocopes-` to give it a unique namespace.

Inside the package I added a `package.json` file with the module name in the `name` property and a few dependencies:

```json
{
  "name": "flaviocopes-common-database",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "dependencies": {
    "pg": "^8.0.2",
    "sequelize": "^5.21.6"
  }
}
```

Then I ran

```
npm link
```

This created a symbolic link in the `/usr/local/lib/node_modules/` folder, that contains the global npm packages in the system, the ones installed using `npm -g`, to be clear.

I had

```
/usr/local/lib/node_modules/flaviocopes-common-database
```

Pointing to the local file I had in

```
/Users/flavio/dev/code/flaviocopes-common-database
```

Now in another project I wanted to use this module, so I ran

```
npm link flaviocopes-common-database
```

and I was able to import it in the [Node.js](https://flaviocopes.com/nodejs/) code using the usual `require()` syntax:

```js
const database = require('flaviocopes-common-database')
```