config

More than you probably want to know about npm configuration

Table of contents

Description

This article details npm configuration in general. To learn about the config command, see npm config.

npm gets its configuration values from the following sources, sorted by priority:

Command Line Flags

Putting --foo bar on the command line sets the foo configuration parameter to "bar". A -- argument tells the cli parser to stop reading flags. Using --flag without specifying any value will set the value to true.

Example: --flag1 --flag2 will set both configuration parameters to true, while --flag1 --flag2 bar will set flag1 to true, and flag2 to bar. Finally, --flag1 --flag2 -- bar will set both configuration parameters to true, and the bar is taken as a command argument.

Environment Variables

Any environment variables that start with npm_config_ will be interpreted as a configuration parameter. For example, putting npm_config_foo=bar in your environment will set the foo configuration parameter to bar. Any environment configurations that are not given a value will be given the value of true. Config values are case-insensitive, so NPM_CONFIG_FOO=bar will work the same. However, please note that inside scripts npm will set its own environment variables and Node will prefer those lowercase versions over any uppercase ones that you might set. For details see this issue.

Notice that you need to use underscores instead of dashes, so --allow-same-version would become npm_config_allow_same_version=true.

npmrc Files

The four relevant files are:

See npmrc for more details.

Default Configs

Run npm config ls -l to see a set of configuration parameters that are internal to npm, and are defaults if nothing else is specified.

Shorthands and Other CLI Niceties

The following shorthands are parsed on the command-line:

If the specified configuration param resolves unambiguously to a known configuration parameter, then it is expanded to that configuration parameter. For example:

npm ls --par
# same as:
npm ls --parseable

If multiple single-character shorthands are strung together, and the resulting combination is unambiguously not some other configuration param, then it is expanded to its various component pieces. For example:

npm ls -gpld
# same as:
npm ls --global --parseable --long --loglevel info

Config Settings

_auth

A basic-auth string to use when authenticating against the npm registry. This will ONLY be used to authenticate against the npm registry. For other registries you will need to scope it like "//other-registry.tld/:_auth"

Warning: This should generally not be set via a command-line option. It is safer to use a registry-provided authentication bearer token stored in the ~/.npmrc file by running npm login.

access

If you do not want your scoped package to be publicly viewable (and installable) set --access=restricted.

Unscoped packages can not be set to restricted.

Note: This defaults to not changing the current access level for existing packages. Specifying a value of restricted or public during publish will change the access for an existing package the same way that npm access set status would.

all

When running npm outdated and npm ls, setting --all will show all outdated or installed packages, rather than only those directly depended upon by the current project.

allow-same-version

Prevents throwing an error when npm version is used to set the new version to the same value as the current version.

audit

When "true" submit audit reports alongside the current npm command to the default registry and all registries configured for scopes. See the documentation for npm audit for details on what is submitted.

audit-level

The minimum level of vulnerability for npm audit to exit with a non-zero exit code.

auth-type

What authentication strategy to use with login. Note that if an otp config is given, this value will always be set to legacy.

before

If passed to npm install, will rebuild the npm tree such that only versions that were available on or before the --before time get installed. If there's no versions available for the current set of direct dependencies, the command will error.

If the requested version is a dist-tag and the given tag does not pass the --before filter, the most recent version less than or equal to that tag will be used. For example, foo@latest might install foo@1.2 even though latest is 2.0.

Tells npm to create symlinks (or .cmd shims on Windows) for package executables.

Set to false to have it not do this. This can be used to work around the fact that some file systems don't support symlinks, even on ostensibly Unix systems.

browser

The browser that is called by npm commands to open websites.

Set to false to suppress browser behavior and instead print urls to terminal.

Set to true to use default system URL opener.

ca

The Certificate Authority signing certificate that is trusted for SSL connections to the registry. Values should be in PEM format (Windows calls it "Base-64 encoded X.509 (.CER)") with newlines replaced by the string "\n". For example:

ca="-----BEGIN CERTIFICATE-----\nXXXX\nXXXX\n-----END CERTIFICATE-----"

Set to null to only allow "known" registrars, or to a specific CA cert to trust only that specific signing authority.

Multiple CAs can be trusted by specifying an array of certificates:

ca[]="..."
ca[]="..."

See also the strict-ssl config.

cache

The location of npm's cache directory.

cafile

A path to a file containing one or multiple Certificate Authority signing certificates. Similar to the ca setting, but allows for multiple CA's, as well as for the CA information to be stored in a file on disk.

call

Optional companion option for npm exec, npx that allows for specifying a custom command to be run along with the installed packages.

npm exec --package yo --package generator-node --call "yo node"

cidr

This is a list of CIDR address to be used when configuring limited access tokens with the npm token create command.

color

If false, never shows colors. If "always" then always shows colors. If true, then only prints color codes for tty file descriptors.

commit-hooks

Run git commit hooks when using the npm version command.

cpu

Override CPU architecture of native modules to install. Acceptable values are same as cpu field of package.json, which comes from process.arch.

depth

The depth to go when recursing packages for npm ls.

If not set, npm ls will show only the immediate dependencies of the root project. If --all is set, then npm will show all dependencies by default.

description

Show the description in npm search

diff

Define arguments to compare in npm diff.

diff-dst-prefix

Destination prefix to be used in npm diff output.

diff-ignore-all-space

Ignore whitespace when comparing lines in npm diff.

diff-name-only

Prints only filenames when using npm diff.

diff-no-prefix

Do not show any source or destination prefix in npm diff output.

Note: this causes npm diff to ignore the --diff-src-prefix and --diff-dst-prefix configs.

diff-src-prefix

Source prefix to be used in npm diff output.

diff-text

Treat all files as text in npm diff.

diff-unified

The number of lines of context to print in npm diff.

dry-run

Indicates that you don't want npm to make any changes and that it should only report what it would have done. This can be passed into any of the commands that modify your local installation, eg, install, update, dedupe, uninstall, as well as pack and publish.

Note: This is NOT honored by other network related commands, eg dist-tags, owner, etc.

editor

The command to run for npm edit and npm config edit.

engine-strict

If set to true, then npm will stubbornly refuse to install (or even consider installing) any package that claims to not be compatible with the current Node.js version.

This can be overridden by setting the --force flag.

expect-result-count

Tells to expect a specific number of results from the command.

This config can not be used with: expect-results

expect-results

Tells npm whether or not to expect results from the command. Can be either true (expect some results) or false (expect no results).

This config can not be used with: expect-result-count

fetch-retries

The "retries" config for the retry module to use when fetching packages from the registry.

npm will retry idempotent read requests to the registry in the case of network failures or 5xx HTTP errors.

fetch-retry-factor

The "factor" config for the retry module to use when fetching packages.

fetch-retry-maxtimeout

The "maxTimeout" config for the retry module to use when fetching packages.

fetch-retry-mintimeout

The "minTimeout" config for the retry module to use when fetching packages.

fetch-timeout

The maximum amount of time to wait for HTTP requests to complete.

force

Removes various protections against unfortunate side effects, common mistakes, unnecessary performance degradation, and malicious input.

If you don't have a clear idea of what you want to do, it is strongly recommended that you do not use this option!

foreground-scripts

Run all build scripts (ie, preinstall, install, and postinstall) scripts for installed packages in the foreground process, sharing standard input, output, and error with the main npm process.

Note that this will generally make installs run slower, and be much noisier, but can be useful for debugging.

format-package-lock

Format package-lock.json or npm-shrinkwrap.json as a human readable file.

fund

When "true" displays the message at the end of each npm install acknowledging the number of dependencies looking for funding. See npm fund for details.

git

The command to use for git commands. If git is installed on the computer, but is not in the PATH, then set this to the full path to the git binary.

git-tag-version

Tag the commit when using the npm version command. Setting this to false results in no commit being made at all.

global

Operates in "global" mode, so that packages are installed into the prefix folder instead of the current working directory. See folders for more on the differences in behavior.

globalconfig

The config file to read for global config options.

heading

The string that starts all the debugging log output.

https-proxy

A proxy to use for outgoing https requests. If the HTTPS_PROXY or https_proxy or HTTP_PROXY or http_proxy environment variables are set, proxy settings will be honored by the underlying make-fetch-happen library.

if-present

If true, npm will not exit with an error code when run-script is invoked for a script that isn't defined in the scripts section of package.json. This option can be used when it's desirable to optionally run a script when it's present and fail if the script fails. This is useful, for example, when running scripts that may only apply for some builds in an otherwise generic CI setup.

This value is not exported to the environment for child processes.

ignore-scripts

If true, npm does not run scripts specified in package.json files.

Note that commands explicitly intended to run a particular script, such as npm start, npm stop, npm restart, npm test, and npm run-script will still run their intended script if ignore-scripts is set, but they will not run any pre- or post-scripts.

include

Option that allows for defining which types of dependencies to install.

This is the inverse of --omit=<type>.

Dependency types specified in --include will not be omitted, regardless of the order in which omit/include are specified on the command-line.

include-staged

Allow installing "staged" published packages, as defined by npm RFC PR #92.

This is experimental, and not implemented by the npm public registry.

include-workspace-root

Include the workspace root when workspaces are enabled for a command.

When false, specifying individual workspaces via the workspace config, or all workspaces via the workspaces flag, will cause npm to operate only on the specified workspaces, and not on the root project.

This value is not exported to the environment for child processes.

init-author-email

The value npm init should use by default for the package author's email.

init-author-name

The value npm init should use by default for the package author's name.

init-author-url

The value npm init should use by default for the package author's homepage.

init-license

The value npm init should use by default for the package license.

init-module

A module that will be loaded by the npm init command. See the documentation for the init-package-json module for more information, or npm init.

init-version

The value that npm init should use by default for the package version number, if not already set in package.json.

When set file: protocol dependencies will be packed and installed as regular dependencies instead of creating a symlink. This option has no effect on workspaces.

install-strategy

Sets the strategy for installing packages in node_modules. hoisted (default): Install non-duplicated in top-level, and duplicated as necessary within directory structure. nested: (formerly --legacy-bundling) install in place, no hoisting. shallow (formerly --global-style) only install direct deps at top-level. linked: (experimental) install in node_modules/.store, link in place, unhoisted.

json

Whether or not to output JSON data, rather than the normal output.

Not supported by all npm commands.

legacy-peer-deps

Causes npm to completely ignore peerDependencies when building a package tree, as in npm versions 3 through 6.

If a package cannot be installed because of overly strict peerDependencies that collide, it provides a way to move forward resolving the situation.

This differs from --omit=peer, in that --omit=peer will avoid unpacking peerDependencies on disk, but will still design a tree such that peerDependencies could be unpacked in a correct place.

Use of legacy-peer-deps is not recommended, as it will not enforce the peerDependencies contract that meta-dependencies may rely on.

libc

Override libc of native modules to install. Acceptable values are same as libc field of package.json

Used with npm ls, limiting output to only those packages that are linked.

local-address

The IP address of the local interface to use when making connections to the npm registry. Must be IPv4 in versions of Node prior to 0.12.

location

When passed to npm config this refers to which config file to use.

When set to "global" mode, packages are installed into the prefix folder instead of the current working directory. See folders for more on the differences in behavior.

lockfile-version

Set the lockfile format version to be used in package-lock.json and npm-shrinkwrap-json files. Possible options are:

1: The lockfile version used by npm versions 5 and 6. Lacks some data that is used during the install, resulting in slower and possibly less deterministic installs. Prevents lockfile churn when interoperating with older npm versions.

2: The default lockfile version used by npm version 7 and 8. Includes both the version 1 lockfile data and version 3 lockfile data, for maximum determinism and interoperability, at the expense of more bytes on disk.

3: Only the new lockfile information introduced in npm version 7. Smaller on disk than lockfile version 2, but not interoperable with older npm versions. Ideal if all users are on npm version 7 and higher.

loglevel

What level of logs to report. All logs are written to a debug log, with the path to that file printed if the execution of a command fails.

Any logs of a higher level than the setting are shown. The default is "notice".

See also the foreground-scripts config.

logs-dir

The location of npm's log directory. See npm logging for more information.

logs-max

The maximum number of log files to store.

If set to 0, no log files will be written for the current run.

long

Show extended information in ls, search, and help-search.

maxsockets

The maximum number of connections to use per origin (protocol/host/port combination).

message

Commit message which is used by npm version when creating version commit.

Any "%s" in the message will be replaced with the version number.

node-options

Options to pass through to Node.js via the NODE_OPTIONS environment variable. This does not impact how npm itself is executed but it does impact how lifecycle scripts are called.

noproxy

Domain extensions that should bypass any proxies.

Also accepts a comma-delimited string.

offline

Force offline mode: no network requests will be done during install. To allow the CLI to fill in missing cache data, see --prefer-offline.

omit

Dependency types to omit from the installation tree on disk.

Note that these dependencies are still resolved and added to the package-lock.json or npm-shrinkwrap.json file. They are just not physically installed on disk.

If a package type appears in both the --include and --omit lists, then it will be included.

If the resulting omit list includes 'dev', then the NODE_ENV environment variable will be set to 'production' for all lifecycle scripts.

omit-lockfile-registry-resolved

This option causes npm to create lock files without a resolved key for registry dependencies. Subsequent installs will need to resolve tarball endpoints with the configured registry, likely resulting in a longer install time.

os

Override OS of native modules to install. Acceptable values are same as os field of package.json, which comes from process.platform.

otp

This is a one-time password from a two-factor authenticator. It's needed when publishing or changing package permissions with npm access.

If not set, and a registry response fails with a challenge for a one-time password, npm will prompt on the command line for one.

pack-destination

Directory in which npm pack will save tarballs.

package

The package or packages to install for npm exec

package-lock

If set to false, then ignore package-lock.json files when installing. This will also prevent writing package-lock.json if save is true.

package-lock-only

If set to true, the current operation will only use the package-lock.json, ignoring node_modules.

For update this means only the package-lock.json will be updated, instead of checking node_modules and downloading dependencies.

For list this means the output will be based on the tree described by the package-lock.json, rather than the contents of node_modules.

parseable

Output parseable results from commands that write to standard output. For npm search, this will be tab-separated table format.

prefer-dedupe

Prefer to deduplicate packages if possible, rather than choosing a newer version of a dependency.

prefer-offline

If true, staleness checks for cached data will be bypassed, but missing data will be requested from the server. To force full offline mode, use --offline.

prefer-online

If true, staleness checks for cached data will be forced, making the CLI look for updates immediately even for fresh package data.

prefix

The location to install global items. If set on the command line, then it forces non-global commands to run in the specified folder.

preid

The "prerelease identifier" to use as a prefix for the "prerelease" part of a semver. Like the rc in 1.2.0-rc.8.

progress

When set to true, npm will display a progress bar during time intensive operations, if process.stderr is a TTY.

Set to false to suppress the progress bar.

provenance

When publishing from a supported cloud CI/CD system, the package will be publicly linked to where it was built and published from.

This config can not be used with: provenance-file

provenance-file

When publishing, the provenance bundle at the given path will be used.

This config can not be used with: provenance

proxy

A proxy to use for outgoing http requests. If the HTTP_PROXY or http_proxy environment variables are set, proxy settings will be honored by the underlying request library.

read-only

This is used to mark a token as unable to publish when configuring limited access tokens with the npm token create command.

rebuild-bundle

Rebuild bundled dependencies after installation.

registry

The base URL of the npm registry.

replace-registry-host

Defines behavior for replacing the registry host in a lockfile with the configured registry.

The default behavior is to replace package dist URLs from the default registry (https://registry.npmjs.org) to the configured registry. If set to "never", then use the registry value. If set to "always", then replace the registry host with the configured host every time.

You may also specify a bare hostname (e.g., "registry.npmjs.org").

save

Save installed packages to a package.json file as dependencies.

When used with the npm rm command, removes the dependency from package.json.

Will also prevent writing to package-lock.json if set to false.

save-bundle

If a package would be saved at install time by the use of --save, --save-dev, or --save-optional, then also put it in the bundleDependencies list.

Ignored if --save-peer is set, since peerDependencies cannot be bundled.

save-dev

Save installed packages to a package.json file as devDependencies.

save-exact

Dependencies saved to package.json will be configured with an exact version rather than using npm's default semver range operator.

save-optional

Save installed packages to a package.json file as optionalDependencies.

save-peer

Save installed packages to a package.json file as peerDependencies

save-prefix

Configure how versions of packages installed to a package.json file via --save or --save-dev get prefixed.

For example if a package has version 1.2.3, by default its version is set to ^1.2.3 which allows minor upgrades for that package, but after npm config set save-prefix='~' it would be set to ~1.2.3 which only allows patch upgrades.

save-prod

Save installed packages into dependencies specifically. This is useful if a package already exists in devDependencies or optionalDependencies, but you want to move it to be a non-optional production dependency.

This is the default behavior if --save is true, and neither --save-dev or --save-optional are true.

sbom-format

SBOM format to use when generating SBOMs.

sbom-type

The type of package described by the generated SBOM. For SPDX, this is the value for the primaryPackagePurpose field. For CycloneDX, this is the value for the type field.

scope

Associate an operation with a scope for a scoped registry.

Useful when logging in to or out of a private registry:

# log in, linking the scope to the custom registry
npm login --scope=@mycorp --registry=https://registry.mycorp.com

# log out, removing the link and the auth token
npm logout --scope=@mycorp

This will cause @mycorp to be mapped to the registry for future installation of packages specified according to the pattern @mycorp/package.

This will also cause npm init to create a scoped package.

# accept all defaults, and create a package named "@foo/whatever",
# instead of just named "whatever"
npm init --scope=@foo --yes

script-shell

The shell to use for scripts run with the npm exec, npm run and npm init <package-spec> commands.

searchexclude

Space-separated options that limit the results from search.

searchlimit

Number of items to limit search results to. Will not apply at all to legacy searches.

searchopts

Space-separated options that are always passed to search.

searchstaleness

The age of the cache, in seconds, before another registry request is made if using legacy search endpoint.

shell

The shell to run for the npm explore command.

sign-git-commit

If set to true, then the npm version command will commit the new package version using -S to add a signature.

Note that git requires you to have set up GPG keys in your git configs for this to work properly.

sign-git-tag

If set to true, then the npm version command will tag the version using -s to add a signature.

Note that git requires you to have set up GPG keys in your git configs for this to work properly.

strict-peer-deps

If set to true, and --legacy-peer-deps is not set, then any conflicting peerDependencies will be treated as an install failure, even if npm could reasonably guess the appropriate resolution based on non-peer dependency relationships.

By default, conflicting peerDependencies deep in the dependency graph will be resolved using the nearest non-peer dependency specification, even if doing so will result in some packages receiving a peer dependency outside the range set in their package's peerDependencies object.

When such an override is performed, a warning is printed, explaining the conflict and the packages involved. If --strict-peer-deps is set, then this warning is treated as a failure.

strict-ssl

Whether or not to do SSL key validation when making requests to the registry via https.

See also the ca config.

tag

If you ask npm to install a package and don't tell it a specific version, then it will install the specified tag.

Also the tag that is added to the package@version specified by the npm tag command, if no explicit tag is given.

When used by the npm diff command, this is the tag used to fetch the tarball that will be compared with the local files by default.

tag-version-prefix

If set, alters the prefix used when tagging a new version when performing a version increment using npm version. To remove the prefix altogether, set it to the empty string: "".

Because other tools may rely on the convention that npm version tags look like v1.0.0, only use this property if it is absolutely necessary. In particular, use care when overriding this setting for public packages.

timing

If true, writes timing information to a process specific json file in the cache or logs-dir. The file name ends with -timing.json.

You can quickly view it with this json command line: cat ~/.npm/_logs/*-timing.json | npm exec -- json -g.

Timing information will also be reported in the terminal. To suppress this while still writing the timing file, use --silent.

umask

The "umask" value to use when setting the file creation mode on files and folders.

Folders and executables are given a mode which is 0o777 masked against this value. Other files are given a mode which is 0o666 masked against this value.

Note that the underlying system will also apply its own umask value to files and folders that are created, and npm does not circumvent this, but rather adds the --umask config to it.

Thus, the effective default umask value on most POSIX systems is 0o22, meaning that folders and executables are created with a mode of 0o755 and other files are created with a mode of 0o644.

unicode

When set to true, npm uses unicode characters in the tree output. When false, it uses ascii characters instead of unicode glyphs.

update-notifier

Set to false to suppress the update notification when using an older version of npm than the latest.

usage

Show short usage output about the command specified.

user-agent

Sets the User-Agent request header. The following fields are replaced with their actual counterparts:

userconfig

The location of user-level configuration settings.

This may be overridden by the npm_config_userconfig environment variable or the --userconfig command line option, but may not be overridden by settings in the globalconfig file.

version

If true, output the npm version and exit successfully.

Only relevant when specified explicitly on the command line.

versions

If true, output the npm version as well as node's process.versions map and the version in the current working directory's package.json file if one exists, and exit successfully.

Only relevant when specified explicitly on the command line.

viewer

The program to use to view help content.

Set to "browser" to view html help content in the default web browser.

which

If there are multiple funding sources, which 1-indexed source URL to open.

workspace

Enable running a command in the context of the configured workspaces of the current project while filtering by running only the workspaces defined by this configuration option.

Valid values for the workspace config are either:

When set for the npm init command, this may be set to the folder of a workspace which does not yet exist, to create the folder and set it up as a brand new workspace within the project.

This value is not exported to the environment for child processes.

workspaces

Set to true to run the command in the context of all configured workspaces.

Explicitly setting this to false will cause commands like install to ignore workspaces altogether. When not set explicitly:

This value is not exported to the environment for child processes.

workspaces-update

If set to true, the npm cli will run an update after operations that may possibly change the workspaces installed to the node_modules folder.

yes

Automatically answer "yes" to any prompts that npm might print on the command line.

also

When set to dev or development, this is an alias for --include=dev.

cache-max

--cache-max=0 is an alias for --prefer-online

cache-min

--cache-min=9999 (or bigger) is an alias for --prefer-offline.

cert

A client certificate to pass when accessing the registry. Values should be in PEM format (Windows calls it "Base-64 encoded X.509 (.CER)") with newlines replaced by the string "\n". For example:

cert="-----BEGIN CERTIFICATE-----\nXXXX\nXXXX\n-----END CERTIFICATE-----"

It is not the path to a certificate file, though you can set a registry-scoped "certfile" path like "//other-registry.tld/:certfile=/path/to/cert.pem".

dev

Alias for --include=dev.

global-style

Only install direct dependencies in the top level node_modules, but hoist on deeper dependencies. Sets --install-strategy=shallow.

init.author.email

Alias for --init-author-email

init.author.name

Alias for --init-author-name

init.author.url

Alias for --init-author-url

init.license

Alias for --init-license

init.module

Alias for --init-module

init.version

Alias for --init-version

key

A client key to pass when accessing the registry. Values should be in PEM format with newlines replaced by the string "\n". For example:

key="-----BEGIN PRIVATE KEY-----\nXXXX\nXXXX\n-----END PRIVATE KEY-----"

It is not the path to a key file, though you can set a registry-scoped "keyfile" path like "//other-registry.tld/:keyfile=/path/to/key.pem".

legacy-bundling

Instead of hoisting package installs in node_modules, install packages in the same manner that they are depended on. This may cause very deep directory structures and duplicate package installs as there is no de-duplicating. Sets --install-strategy=nested.

only

When set to prod or production, this is an alias for --omit=dev.

optional

Default value does install optional deps unless otherwise omitted.

Alias for --include=optional or --omit=optional

production

Alias for --omit=dev

shrinkwrap

Alias for --package-lock

See also