# Workspaces

The main concept of Multijet is the same as every other Node.js based monorepo: **workspaces**.

To know more about workspaces, you can read the official [npm workspaces documentation](https://docs.npmjs.com/cli/v7/using-npm/workspaces).

In Multijet, there are **two workspaces** by default:

* **microservices**
* **libs**

{% hint style="info" %}
Workspaces are defined in the project's root `package.json` file.
{% endhint %}

## Microservices

Inside this workspace by default there are **multiple** **Node.js projects** using the `Fastify` web framework. If you just created a new project, you will find an example microservice running a simple `hello-world` REST API.

By default, microservices can install and use shared packages in the `libs` workspace**.**  

## Libs 

As the `microservices` workspace, this one also can contain multiple Node.js projects. These packages can be installed and used either by a microservice or by another lib.

## Example

Let's say you have a project with the following structure:

```
my-project/
├── libs/
│   ├── lib-A
│   └── lib-B
└── microservices/
    └── microservice-1
```

For this example, we want to use `lib-A` in `microservice-1`, and `lib-B` in `lib-A`

First, let's install `lib-B` as a dependency of `lib-A`. In the root of your project run this command:

```bash
npm install @libs/lib-B -w libs/lib-A
```

This command is a standard `npm install` but, instaed of installing a package from the npm registry, we actually add a local package (`lib-B`) contained in the **libs workspace**.

If we didn't include `-w libs/lib-A` npm would have installed the package globally in the project. By using the `-w` option we tell npm to install that package for the specific project in the workspace (in this case the workspace is `libs` and the project is `lib-A`)

Now that we have installed `lib-B` in `lib-A`, you can probably guess how we can do this with `microservice-1` and `lib-A`:

```bash
npm install @libs/lib-A -w microservices/microservice-1
```

Note that the `-w` option is **not required** if you are already in the directory of the project that needs the dependency:

```bash
cd microservices/microservice-1
npm install @libs/lib-A
```

This will do the same exact thing as the previous command.