Workspace
pnpm has built-in support for monorepositories (AKA multi-package repositories, multi-project repositories, or monolithic repositories). You can create a workspace to unite multiple projects inside a single repository.
A workspace must have a pnpm-workspace.yaml file in its root. A workspace also may have an .npmrc in its root.
If you are looking into monorepo management, you might also want to look into Bit. Bit uses pnpm under the hood but automates a lot of the things that are currently done manually in a traditional workspace managed by pnpm/npm/Yarn. There's an article about bit install that talks about it: Painless Monorepo Dependency Management with Bit.
Workspace protocol (workspace:)
If link-workspace-packages is set to true, pnpm will link packages from the workspace if the available packages match the declared ranges. For instance, foo@1.0.0 is linked into bar if bar has "foo": "^1.0.0" in its dependencies and foo@1.0.0 is in the workspace. However, if bar has "foo": "2.0.0" in dependencies and foo@2.0.0 is not in the workspace, foo@2.0.0 will be installed from the registry. This behavior introduces some uncertainty.
Luckily, pnpm supports the workspace: protocol. When this protocol is used, pnpm will refuse to resolve to anything other than a local workspace package. So, if you set "foo": "workspace:2.0.0", this time installation will fail because "foo@2.0.0" isn't present in the workspace.
This protocol is especially useful when the link-workspace-packages option is set to false. In that case, pnpm will only link packages from the workspace if the workspace: protocol is used.
Referencing workspace packages through aliases
Let's say you have a package in the workspace named foo. Usually, you would reference it as "foo": "workspace:*".
If you want to use a different alias, the following syntax will work too: "bar": "workspace:foo@*".
Before publish, aliases are converted to regular aliased dependencies. The above example will become: "bar": "npm:foo@1.0.0".
Referencing workspace packages through their relative path
In a workspace with 2 packages:
+ packages
+ foo
+ bar
bar may have foo in its dependencies declared as "foo": "workspace:../foo". Before publishing, these specs are converted to regular version specs supported by all package managers.
Publishing workspace packages
When a workspace package is packed into an archive (whether it's through pnpm pack or one of the publish commands like pnpm publish), we dynamically replace any workspace: dependency by:
- The corresponding version in the target workspace (if you use
workspace:*,workspace:~, orworkspace:^) - The associated semver range (for any other range type)
So for example, if we have foo, bar, qar, zoo in the workspace and they all are at version 1.5.0, the following:
{
"dependencies": {
"foo": "workspace:*",
"bar": "workspace:~",
"qar": "workspace:^",
"zoo": "workspace:^1.5.0"
}
}
Will be transformed into:
{
"dependencies": {
"foo": "1.5.0",
"bar": "~1.5.0",
"qar": "^1.5.0",
"zoo": "^1.5.0"
}
}
This feature allows you to depend on your local workspace packages while still being able to publish the resulting packages to the remote registry without needing intermediary publish steps - your consumers will be able to use your published workspaces as any other package, still benefitting from the guarantees semver offers.
Release workflow
Versioning packages inside a workspace is a complex task and pnpm currently does not provide a built-in solution for it. However, there are 2 well tested tools that handle versioning and support pnpm:
For how to set up a repository using Rush, read this page.
For using Changesets with pnpm, read this guide.
Troubleshooting
pnpm cannot guarantee that scripts will be run in topological order if there are cycles between workspace dependencies. If pnpm detects cyclic dependencies during installation, it will produce a warning. If pnpm is able to find out which dependencies are causing the cycles, it will display them too.
If you see the message There are cyclic workspace dependencies, please inspect workspace dependencies declared in dependencies, optionalDependencies and devDependencies.
Usage examples
Here are a few of the most popular open source projects that use the workspace feature of pnpm:
