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---
title: workspaces
section: 7
description: Working with workspaces
---
### Description
**Workspaces** is a generic term that refers to the set of features in the
npm cli that provides support to managing multiple packages from your local
files system from within a singular top-level, root package.
This set of features makes up for a much more streamlined workflow handling
linked packages from the local file system. Automating the linking process
as part of `npm install` and avoiding manually having to use `npm link` in
order to add references to packages that should be symlinked into the current
`node_modules` folder.
We also refer to these packages being auto-symlinked during `npm install` as a
single **workspace**, meaning it's a nested package within the current local
file system that is explicitly defined in the [`package.json`](/configuring-npm/package-json#workspaces)
`workspaces` configuration.
### Defining workspaces
Workspaces are usually defined via the `workspaces` property of the
[`package.json`](/configuring-npm/package-json#workspaces) file, e.g:
```json
{
"name": "my-workspaces-powered-project",
"workspaces": [
"workspace-a"
]
}
```
Given the above `package.json` example living at a current working
directory `.` that contains a folder named `workspace-a` that itself contains
a `package.json` inside it, defining a Node.js package, e.g:
```
.
+-- package.json
`-- workspace-a
`-- package.json
```
The expected result once running `npm install` in this current working
directory `.` is that the folder `workspace-a` will get symlinked to the
`node_modules` folder of the current working dir.
Below is a post `npm install` example, given that same previous example
structure of files and folders:
```
.
+-- node_modules
| `-- workspace-a -> ../workspace-a
+-- package-lock.json
+-- package.json
`-- workspace-a
`-- package.json
```
### Getting started with workspaces
You may automate the required steps to define a new workspace using
[npm init](/commands/npm-init). For example in a project that already has a
`package.json` defined you can run:
```
npm init -w ./packages/a
```
This command will create the missing folders and a new `package.json`
file (if needed) while also making sure to properly configure the
`"workspaces"` property of your root project `package.json`.
### Adding dependencies to a workspace
It's possible to directly add/remove/update dependencies of your workspaces
using the [`workspace` config](/using-npm/config#workspace).
For example, assuming the following structure:
```
.
+-- package.json
`-- packages
+-- a
| `-- package.json
`-- b
`-- package.json
```
If you want to add a dependency named `abbrev` from the registry as a
dependency of your workspace **a**, you may use the workspace config to tell
the npm installer that package should be added as a dependency of the provided
workspace:
```
npm install abbrev -w a
```
Note: other installing commands such as `uninstall`, `ci`, etc will also
respect the provided `workspace` configuration.
### Using workspaces
Given the [specifities of how Node.js handles module resolution](https://nodejs.org/dist/latest-v14.x/docs/api/modules.html#modules_all_together) it's possible to consume any defined workspace
by it's declared `package.json` `name`. Continuing from the example defined
above, let's also create a Node.js script that will require the `workspace-a`
example module, e.g:
```
// ./workspace-a/index.js
module.exports = 'a'
// ./lib/index.js
const moduleA = require('workspace-a')
console.log(moduleA) // -> a
```
When running it with:
`node lib/index.js`
This demonstrates how the nature of `node_modules` resolution allows for
**workspaces** to enable a portable workflow for requiring each **workspace**
in such a way that is also easy to [publish](/commands/npm-publish) these
nested workspaces to be consumed elsewhere.
### Running commands in the context of workspaces
You can use the `workspace` configuration option to run commands in the context
of a configured workspace.
Following is a quick example on how to use the `npm run` command in the context
of nested workspaces. For a project containing multiple workspaces, e.g:
```
.
+-- package.json
`-- packages
+-- a
| `-- package.json
`-- b
`-- package.json
```
By running a command using the `workspace` option, it's possible to run the
given command in the context of that specific workspace. e.g:
```
npm run test --workspace=a
```
This will run the `test` script defined within the
`./packages/a/package.json` file.
Please note that you can also specify this argument multiple times in the
command-line in order to target multiple workspaces, e.g:
```
npm run test --workspace=a --workspace=b
```
It's also possible to use the `workspaces` (plural) configuration option to
enable the same behavior but running that command in the context of **all**
configured workspaces. e.g:
```
npm run test --workspaces
```
Will run the `test` script in both `./packages/a` and `./packages/b`.
### Ignoring missing scripts
It is not required for all of the workspaces to implement scripts run with the `npm run` command.
By running the command with the `--if-present` flag, npm will ignore workspaces missing target script.
```
npm run test --workspaces --if-present
```
### See also
* [npm install](/commands/npm-install)
* [npm publish](/commands/npm-publish)
* [npm run-script](/commands/npm-run-script)
* [config](/using-npm/config)
|
