package.json
The manifest file of a package. It contains all the package's metadata, including dependencies, title, author, et cetera. This is a standard preserved across all major Node.js package managers, including pnpm.
engines
You can specify the version of Node and pnpm that your software works on:
If you find that your use of a certain package doesn’t require one of its dependencies, you may use -
to remove it. For example, if package foo@1.0.0
requires a large package named bar
for a function that you don’t use, removing it could reduce install time:
{
"pnpm": {
"overrides": {
"foo@1.0.0>bar": "-"
}
}
}
This feature is especially useful with optionalDependencies
, where most optional packages can be safely skipped.
pnpm.packageExtensions
The packageExtensions
fields offer a way to extend the existing package definitions with additional information. For example, if react-redux
should have react-dom
in its peerDependencies
but it has not, it is possible to patch react-redux
using packageExtensions
:
{
"pnpm": {
"packageExtensions": {
"react-redux": {
"peerDependencies": {
"react-dom": "*"
}
}
}
}
}
The keys in packageExtensions
are package names or package names and semver ranges, so it is possible to patch only some versions of a package:
{
"pnpm": {
"packageExtensions": {
"react-redux@1": {
"peerDependencies": {
"react-dom": "*"
}
}
}
}
}
The following fields may be extended using packageExtensions
: dependencies
, optionalDependencies
, peerDependencies
, and peerDependenciesMeta
.
A bigger example:
{
"pnpm": {
"packageExtensions": {
"express@1": {
"optionalDependencies": {
"typescript": "2"
}
},
"fork-ts-checker-webpack-plugin": {
"dependencies": {
"@babel/core": "1"
},
"peerDependencies": {
"eslint": ">= 6"
},
"peerDependenciesMeta": {
"eslint": {
"optional": true
}
}
}
}
}
}
Together with Yarn, we maintain a database of packageExtensions
to patch broken packages in the ecosystem.
If you use packageExtensions
, consider sending a PR upstream and contributing your extension to the @yarnpkg/extensions
database.
pnpm.peerDependencyRules
pnpm.peerDependencyRules.ignoreMissing
pnpm will not print warnings about missing peer dependencies from this list.
For instance, with the following configuration, pnpm will not print warnings if a dependency needs react
but react
is not installed:
{
"pnpm": {
"peerDependencyRules": {
"ignoreMissing": ["react"]
}
}
}
Package name patterns may also be used:
{
"pnpm": {
"peerDependencyRules": {
"ignoreMissing": ["@babel/*", "@eslint/*"]
}
}
}
pnpm.peerDependencyRules.allowedVersions
Unmet peer dependency warnings will not be printed for peer dependencies of the specified range.
For instance, if you have some dependencies that need react@16
but you know that they work fine with react@17
, then you may use the following configuration:
{
"pnpm": {
"peerDependencyRules": {
"allowedVersions": {
"react": "17"
}
}
}
}
This will tell pnpm that any dependency that has react in its peer dependencies should allow react
v17 to be installed.
It is also possible to suppress the warnings only for peer dependencies of specific packages. For instance, with the following configuration react
v17 will be only allowed when it is in the peer dependencies of the button
v2 package or in the dependencies of any card
package:
{
"pnpm": {
"peerDependencyRules": {
"allowedVersions": {
"button@2>react": "17",
"card>react": "17"
}
}
}
}
pnpm.peerDependencyRules.allowAny
allowAny
is an array of package name patterns, any peer dependency matching the pattern will be resolved from any version, regardless of the range specified in peerDependencies
. For instance:
{
"pnpm": {
"peerDependencyRules": {
"allowAny": ["@babel/*", "eslint"]
}
}
}
The above setting will mute any warnings about peer dependency version mismatches related to @babel/
packages or eslint
.