1PACKAGE.JSON(5) PACKAGE.JSON(5)
2
3
4
6 package.json - Specifics of npm's package.json handling
7
8 Description
9 This document is all you need to know about what's required in your
10 package.json file. It must be actual JSON, not just a JavaScript ob‐
11 ject literal.
12
13 A lot of the behavior described in this document is affected by the
14 config settings described in npm help config.
15
16 name
17 If you plan to publish your package, the most important things in your
18 package.json are the name and version fields as they will be required.
19 The name and version together form an identifier that is assumed to be
20 completely unique. Changes to the package should come along with
21 changes to the version. If you don't plan to publish your package, the
22 name and version fields are optional.
23
24 The name is what your thing is called.
25
26 Some rules:
27
28 • The name must be less than or equal to 214 characters. This includes
29 the scope for scoped packages.
30
31 • The names of scoped packages can begin with a dot or an underscore.
32 This is not permitted without a scope.
33
34 • New packages must not have uppercase letters in the name.
35
36 • The name ends up being part of a URL, an argument on the command
37 line, and a folder name. Therefore, the name can't contain any
38 non-URL-safe characters.
39
40
41 Some tips:
42
43 • Don't use the same name as a core Node module.
44
45 • Don't put "js" or "node" in the name. It's assumed that it's js,
46 since you're writing a package.json file, and you can specify the en‐
47 gine using the "engines" field. (See below.)
48
49 • The name will probably be passed as an argument to require(), so it
50 should be something short, but also reasonably descriptive.
51
52 • You may want to check the npm registry to see if there's something by
53 that name already, before you get too attached to it.
54 https://www.npmjs.com/
55
56
57 A name can be optionally prefixed by a scope, e.g. @myorg/mypackage.
58 See npm help scope for more detail.
59
60 version
61 If you plan to publish your package, the most important things in your
62 package.json are the name and version fields as they will be required.
63 The name and version together form an identifier that is assumed to be
64 completely unique. Changes to the package should come along with
65 changes to the version. If you don't plan to publish your package, the
66 name and version fields are optional.
67
68 Version must be parseable by node-semver
69 https://github.com/npm/node-semver, which is bundled with npm as a de‐
70 pendency. (npm install semver to use it yourself.)
71
72 description
73 Put a description in it. It's a string. This helps people discover
74 your package, as it's listed in npm search.
75
76 keywords
77 Put keywords in it. It's an array of strings. This helps people dis‐
78 cover your package as it's listed in npm search.
79
80 homepage
81 The url to the project homepage.
82
83 Example:
84
85 "homepage": "https://github.com/owner/project#readme"
86
87 bugs
88 The url to your project's issue tracker and / or the email address to
89 which issues should be reported. These are helpful for people who en‐
90 counter issues with your package.
91
92 It should look like this:
93
94 {
95 "url" : "https://github.com/owner/project/issues",
96 "email" : "project@hostname.com"
97 }
98
99 You can specify either one or both values. If you want to provide only
100 a url, you can specify the value for "bugs" as a simple string instead
101 of an object.
102
103 If a url is provided, it will be used by the npm bugs command.
104
105 license
106 You should specify a license for your package so that people know how
107 they are permitted to use it, and any restrictions you're placing on
108 it.
109
110 If you're using a common license such as BSD-2-Clause or MIT, add a
111 current SPDX license identifier for the license you're using, like
112 this:
113
114 {
115 "license" : "BSD-3-Clause"
116 }
117
118 You can check the full list of SPDX license IDs https://spdx.org/li‐
119 censes/. Ideally you should pick one that is OSI https://open‐
120 source.org/licenses/alphabetical approved.
121
122 If your package is licensed under multiple common licenses, use an SPDX
123 license expression syntax version 2.0 string
124 https://www.npmjs.com/package/spdx, like this:
125
126 {
127 "license" : "(ISC OR GPL-3.0)"
128 }
129
130 If you are using a license that hasn't been assigned an SPDX identi‐
131 fier, or if you are using a custom license, use a string value like
132 this one:
133
134 {
135 "license" : "SEE LICENSE IN <filename>"
136 }
137
138 Then include a file named <filename> at the top level of the package.
139
140 Some old packages used license objects or a "licenses" property con‐
141 taining an array of license objects:
142
143 // Not valid metadata
144 {
145 "license" : {
146 "type" : "ISC",
147 "url" : "https://opensource.org/licenses/ISC"
148 }
149 }
150
151 // Not valid metadata
152 {
153 "licenses" : [
154 {
155 "type": "MIT",
156 "url": "https://www.opensource.org/licenses/mit-license.php"
157 },
158 {
159 "type": "Apache-2.0",
160 "url": "https://opensource.org/licenses/apache2.0.php"
161 }
162 ]
163 }
164
165 Those styles are now deprecated. Instead, use SPDX expressions, like
166 this:
167
168 {
169 "license": "ISC"
170 }
171
172 {
173 "license": "(MIT OR Apache-2.0)"
174 }
175
176 Finally, if you do not wish to grant others the right to use a private
177 or unpublished package under any terms:
178
179 {
180 "license": "UNLICENSED"
181 }
182
183 Consider also setting "private": true to prevent accidental publica‐
184 tion.
185
186 people fields: author, contributors
187 The "author" is one person. "contributors" is an array of people. A
188 "person" is an object with a "name" field and optionally "url" and
189 "email", like this:
190
191 {
192 "name" : "Barney Rubble",
193 "email" : "b@rubble.com",
194 "url" : "http://barnyrubble.tumblr.com/"
195 }
196
197 Or you can shorten that all into a single string, and npm will parse it
198 for you:
199
200 {
201 "author": "Barney Rubble <b@rubble.com> (http://barnyrubble.tumblr.com/)"
202 }
203
204 Both email and url are optional either way.
205
206 npm also sets a top-level "maintainers" field with your npm user info.
207
208 funding
209 You can specify an object containing an URL that provides up-to-date
210 information about ways to help fund development of your package, or a
211 string URL, or an array of these:
212
213 {
214 "funding": {
215 "type" : "individual",
216 "url" : "http://example.com/donate"
217 },
218
219 "funding": {
220 "type" : "patreon",
221 "url" : "https://www.patreon.com/my-account"
222 },
223
224 "funding": "http://example.com/donate",
225
226 "funding": [
227 {
228 "type" : "individual",
229 "url" : "http://example.com/donate"
230 },
231 "http://example.com/donateAlso",
232 {
233 "type" : "patreon",
234 "url" : "https://www.patreon.com/my-account"
235 }
236 ]
237 }
238
239 Users can use the npm fund subcommand to list the funding URLs of all
240 dependencies of their project, direct and indirect. A shortcut to visit
241 each funding url is also available when providing the project name such
242 as: npm fund <projectname> (when there are multiple URLs, the first one
243 will be visited)
244
245 files
246 The optional files field is an array of file patterns that describes
247 the entries to be included when your package is installed as a depen‐
248 dency. File patterns follow a similar syntax to .gitignore, but re‐
249 versed: including a file, directory, or glob pattern (*, **/*, and
250 such) will make it so that file is included in the tarball when it's
251 packed. Omitting the field will make it default to ["*"], which means
252 it will include all files.
253
254 Some special files and directories are also included or excluded re‐
255 gardless of whether they exist in the files array (see below).
256
257 You can also provide a .npmignore file in the root of your package or
258 in subdirectories, which will keep files from being included. At the
259 root of your package it will not override the "files" field, but in
260 subdirectories it will. The .npmignore file works just like a .gitig‐
261 nore. If there is a .gitignore file, and .npmignore is missing, .gitig‐
262 nore's contents will be used instead.
263
264 Files included with the "package.json#files" field cannot be excluded
265 through .npmignore or .gitignore.
266
267 Certain files are always included, regardless of settings:
268
269 • package.json
270
271 • README
272
273 • LICENSE / LICENCE
274
275 • The file in the "main" field
276
277
278 README & LICENSE can have any case and extension.
279
280 Conversely, some files are always ignored:
281
282 • .git
283
284 • CVS
285
286 • .svn
287
288 • .hg
289
290 • .lock-wscript
291
292 • .wafpickle-N
293
294 • .*.swp
295
296 • .DS_Store
297
298 • ._*
299
300 • npm-debug.log
301
302 • .npmrc
303
304 • node_modules
305
306 • config.gypi
307
308 • *.orig
309
310 • package-lock.json (use npm help npm-shrinkwrap.json if you wish it to
311 be published)
312
313
314 main
315 The main field is a module ID that is the primary entry point to your
316 program. That is, if your package is named foo, and a user installs
317 it, and then does require("foo"), then your main module's exports ob‐
318 ject will be returned.
319
320 This should be a module relative to the root of your package folder.
321
322 For most modules, it makes the most sense to have a main script and of‐
323 ten not much else.
324
325 If main is not set it defaults to index.js in the packages root folder.
326
327 browser
328 If your module is meant to be used client-side the browser field should
329 be used instead of the main field. This is helpful to hint users that
330 it might rely on primitives that aren't available in Node.js modules.
331 (e.g. window)
332
333 bin
334 A lot of packages have one or more executable files that they'd like to
335 install into the PATH. npm makes this pretty easy (in fact, it uses
336 this feature to install the "npm" executable.)
337
338 To use this, supply a bin field in your package.json which is a map of
339 command name to local file name. When this package is installed glob‐
340 ally, that file will be linked where global bins go so it is available
341 to run by name. When this package is installed as a dependency in an‐
342 other package, the file will be linked where it will be available to
343 that package either directly by npm exec or by name in other scripts
344 when invoking them via npm run-script.
345
346 For example, myapp could have this:
347
348 {
349 "bin": {
350 "myapp": "./cli.js"
351 }
352 }
353
354 So, when you install myapp, it'll create a symlink from the cli.js
355 script to /usr/local/bin/myapp.
356
357 If you have a single executable, and its name should be the name of the
358 package, then you can just supply it as a string. For example:
359
360 {
361 "name": "my-program",
362 "version": "1.2.5",
363 "bin": "./path/to/program"
364 }
365
366 would be the same as this:
367
368 {
369 "name": "my-program",
370 "version": "1.2.5",
371 "bin": {
372 "my-program": "./path/to/program"
373 }
374 }
375
376 Please make sure that your file(s) referenced in bin starts with
377 #!/usr/bin/env node, otherwise the scripts are started without the node
378 executable!
379
380 Note that you can also set the executable files using directories.bin
381 #directoriesbin.
382
383 See npm help folders for more info on executables.
384
385 man
386 Specify either a single file or an array of filenames to put in place
387 for the man program to find.
388
389 If only a single file is provided, then it's installed such that it is
390 the result from man <pkgname>, regardless of its actual filename. For
391 example:
392
393 {
394 "name": "foo",
395 "version": "1.2.3",
396 "description": "A packaged foo fooer for fooing foos",
397 "main": "foo.js",
398 "man": "./man/doc.1"
399 }
400
401 would link the ./man/doc.1 file in such that it is the target for man
402 foo
403
404 If the filename doesn't start with the package name, then it's pre‐
405 fixed. So, this:
406
407 {
408 "name": "foo",
409 "version": "1.2.3",
410 "description": "A packaged foo fooer for fooing foos",
411 "main": "foo.js",
412 "man": [
413 "./man/foo.1",
414 "./man/bar.1"
415 ]
416 }
417
418 will create files to do man foo and man foo-bar.
419
420 Man files must end with a number, and optionally a .gz suffix if they
421 are compressed. The number dictates which man section the file is in‐
422 stalled into.
423
424 {
425 "name": "foo",
426 "version": "1.2.3",
427 "description": "A packaged foo fooer for fooing foos",
428 "main": "foo.js",
429 "man": [
430 "./man/foo.1",
431 "./man/foo.2"
432 ]
433 }
434
435 will create entries for man foo and man 2 foo
436
437 directories
438 The CommonJS Packages http://wiki.commonjs.org/wiki/Packages/1.0 spec
439 details a few ways that you can indicate the structure of your package
440 using a directories object. If you look at npm's package.json
441 https://registry.npmjs.org/npm/latest, you'll see that it has directo‐
442 ries for doc, lib, and man.
443
444 In the future, this information may be used in other creative ways.
445
446 directories.bin
447 If you specify a bin directory in directories.bin, all the files in
448 that folder will be added.
449
450 Because of the way the bin directive works, specifying both a bin path
451 and setting directories.bin is an error. If you want to specify indi‐
452 vidual files, use bin, and for all the files in an existing bin direc‐
453 tory, use directories.bin.
454
455 directories.man
456 A folder that is full of man pages. Sugar to generate a "man" array by
457 walking the folder.
458
459 repository
460 Specify the place where your code lives. This is helpful for people who
461 want to contribute. If the git repo is on GitHub, then the npm docs
462 command will be able to find you.
463
464 Do it like this:
465
466 {
467 "repository": {
468 "type": "git",
469 "url": "https://github.com/npm/cli.git"
470 }
471 }
472
473 The URL should be a publicly available (perhaps read-only) url that can
474 be handed directly to a VCS program without any modification. It
475 should not be a url to an html project page that you put in your
476 browser. It's for computers.
477
478 For GitHub, GitHub gist, Bitbucket, or GitLab repositories you can use
479 the same shortcut syntax you use for npm install:
480
481 {
482 "repository": "npm/npm",
483
484 "repository": "github:user/repo",
485
486 "repository": "gist:11081aaa281",
487
488 "repository": "bitbucket:user/repo",
489
490 "repository": "gitlab:user/repo"
491 }
492
493 If the package.json for your package is not in the root directory (for
494 example if it is part of a monorepo), you can specify the directory in
495 which it lives:
496
497 {
498 "repository": {
499 "type": "git",
500 "url": "https://github.com/facebook/react.git",
501 "directory": "packages/react-dom"
502 }
503 }
504
505 scripts
506 The "scripts" property is a dictionary containing script commands that
507 are run at various times in the lifecycle of your package. The key is
508 the lifecycle event, and the value is the command to run at that point.
509
510 See npm help scripts to find out more about writing package scripts.
511
512 config
513 A "config" object can be used to set configuration parameters used in
514 package scripts that persist across upgrades. For instance, if a pack‐
515 age had the following:
516
517 {
518 "name": "foo",
519 "config": {
520 "port": "8080"
521 }
522 }
523
524 It could also have a "start" command that referenced the npm_pack‐
525 age_config_port environment variable.
526
527 dependencies
528 Dependencies are specified in a simple object that maps a package name
529 to a version range. The version range is a string which has one or more
530 space-separated descriptors. Dependencies can also be identified with
531 a tarball or git URL.
532
533 Please do not put test harnesses or transpilers or other "development"
534 time tools in your dependencies object. See devDependencies, below.
535
536 See semver https://github.com/npm/node-semver#versions for more details
537 about specifying version ranges.
538
539 • version Must match version exactly
540
541 • >version Must be greater than version
542
543 • >=version etc
544
545 • <version
546
547 • <=version
548
549 • ~version "Approximately equivalent to version" See semver
550 https://github.com/npm/node-semver#versions
551
552 • ^version "Compatible with version" See semver
553 https://github.com/npm/node-semver#versions
554
555 • 1.2.x 1.2.0, 1.2.1, etc., but not 1.3.0
556
557 • http://... See 'URLs as Dependencies' below
558
559 • * Matches any version
560
561 • "" (just an empty string) Same as *
562
563 • version1 - version2 Same as >=version1 <=version2.
564
565 • range1 || range2 Passes if either range1 or range2 are satisfied.
566
567 • git... See 'Git URLs as Dependencies' below
568
569 • user/repo See 'GitHub URLs' below
570
571 • tag A specific version tagged and published as tag See npm help npm
572 dist-tag
573
574 • path/path/path See Local Paths #local-paths below
575
576
577 For example, these are all valid:
578
579 {
580 "dependencies": {
581 "foo": "1.0.0 - 2.9999.9999",
582 "bar": ">=1.0.2 <2.1.2",
583 "baz": ">1.0.2 <=2.3.4",
584 "boo": "2.0.1",
585 "qux": "<1.0.0 || >=2.3.1 <2.4.5 || >=2.5.2 <3.0.0",
586 "asd": "http://asdf.com/asdf.tar.gz",
587 "til": "~1.2",
588 "elf": "~1.2.3",
589 "two": "2.x",
590 "thr": "3.3.x",
591 "lat": "latest",
592 "dyl": "file:../dyl"
593 }
594 }
595
596 URLs as Dependencies
597 You may specify a tarball URL in place of a version range.
598
599 This tarball will be downloaded and installed locally to your package
600 at install time.
601
602 Git URLs as Dependencies
603 Git urls are of the form:
604
605 <protocol>://[<user>[:<password>]@]<hostname>[:<port>][:][/]<path>[#<commit-ish> | #semver:<semver>]
606
607 <protocol> is one of git, git+ssh, git+http, git+https, or git+file.
608
609 If #<commit-ish> is provided, it will be used to clone exactly that
610 commit. If the commit-ish has the format #semver:<semver>, <semver> can
611 be any valid semver range or exact version, and npm will look for any
612 tags or refs matching that range in the remote repository, much as it
613 would for a registry dependency. If neither #<commit-ish> or
614 #semver:<semver> is specified, then master is used.
615
616 Examples:
617
618 git+ssh://git@github.com:npm/cli.git#v1.0.27
619 git+ssh://git@github.com:npm/cli#semver:^5.0
620 git+https://isaacs@github.com/npm/cli.git
621 git://github.com/npm/cli.git#v1.0.27
622
623 GitHub URLs
624 As of version 1.1.65, you can refer to GitHub urls as just "foo":
625 "user/foo-project". Just as with git URLs, a commit-ish suffix can be
626 included. For example:
627
628 {
629 "name": "foo",
630 "version": "0.0.0",
631 "dependencies": {
632 "express": "expressjs/express",
633 "mocha": "mochajs/mocha#4727d357ea",
634 "module": "user/repo#feature\/branch"
635 }
636 }
637
638 Local Paths
639 As of version 2.0.0 you can provide a path to a local directory that
640 contains a package. Local paths can be saved using npm install -S or
641 npm install --save, using any of these forms:
642
643 ../foo/bar
644 ~/foo/bar
645 ./foo/bar
646 /foo/bar
647
648 in which case they will be normalized to a relative path and added to
649 your package.json. For example:
650
651 {
652 "name": "baz",
653 "dependencies": {
654 "bar": "file:../foo/bar"
655 }
656 }
657
658 This feature is helpful for local offline development and creating
659 tests that require npm installing where you don't want to hit an exter‐
660 nal server, but should not be used when publishing packages to the pub‐
661 lic registry.
662
663 devDependencies
664 If someone is planning on downloading and using your module in their
665 program, then they probably don't want or need to download and build
666 the external test or documentation framework that you use.
667
668 In this case, it's best to map these additional items in a devDependen‐
669 cies object.
670
671 These things will be installed when doing npm link or npm install from
672 the root of a package, and can be managed like any other npm configura‐
673 tion param. See npm help config for more on the topic.
674
675 For build steps that are not platform-specific, such as compiling Cof‐
676 feeScript or other languages to JavaScript, use the prepare script to
677 do this, and make the required package a devDependency.
678
679 For example:
680
681 {
682 "name": "ethopia-waza",
683 "description": "a delightfully fruity coffee varietal",
684 "version": "1.2.3",
685 "devDependencies": {
686 "coffee-script": "~1.6.3"
687 },
688 "scripts": {
689 "prepare": "coffee -o lib/ -c src/waza.coffee"
690 },
691 "main": "lib/waza.js"
692 }
693
694 The prepare script will be run before publishing, so that users can
695 consume the functionality without requiring them to compile it them‐
696 selves. In dev mode (ie, locally running npm install), it'll run this
697 script as well, so that you can test it easily.
698
699 peerDependencies
700 In some cases, you want to express the compatibility of your package
701 with a host tool or library, while not necessarily doing a require of
702 this host. This is usually referred to as a plugin. Notably, your mod‐
703 ule may be exposing a specific interface, expected and specified by the
704 host documentation.
705
706 For example:
707
708 {
709 "name": "tea-latte",
710 "version": "1.3.5",
711 "peerDependencies": {
712 "tea": "2.x"
713 }
714 }
715
716 This ensures your package tea-latte can be installed along with the
717 second major version of the host package tea only. npm install
718 tea-latte could possibly yield the following dependency graph:
719
720 ├── tea-latte@1.3.5
721 └── tea@2.2.0
722
723 In npm versions 3 through 6, peerDependencies were not automatically
724 installed, and would raise a warning if an invalid version of the peer
725 dependency was found in the tree. As of npm v7, peerDependencies are
726 installed by default.
727
728 Trying to install another plugin with a conflicting requirement may
729 cause an error if the tree cannot be resolved correctly. For this rea‐
730 son, make sure your plugin requirement is as broad as possible, and not
731 to lock it down to specific patch versions.
732
733 Assuming the host complies with semver https://semver.org/, only
734 changes in the host package's major version will break your plugin.
735 Thus, if you've worked with every 1.x version of the host package, use
736 "^1.0" or "1.x" to express this. If you depend on features introduced
737 in 1.5.2, use "^1.5.2".
738
739 peerDependenciesMeta
740 When a user installs your package, npm will emit warnings if packages
741 specified in peerDependencies are not already installed. The peerDepen‐
742 denciesMeta field serves to provide npm more information on how your
743 peer dependencies are to be used. Specifically, it allows peer depen‐
744 dencies to be marked as optional.
745
746 For example:
747
748 {
749 "name": "tea-latte",
750 "version": "1.3.5",
751 "peerDependencies": {
752 "tea": "2.x",
753 "soy-milk": "1.2"
754 },
755 "peerDependenciesMeta": {
756 "soy-milk": {
757 "optional": true
758 }
759 }
760 }
761
762 Marking a peer dependency as optional ensures npm will not emit a warn‐
763 ing if the soy-milk package is not installed on the host. This allows
764 you to integrate and interact with a variety of host packages without
765 requiring all of them to be installed.
766
767 bundledDependencies
768 This defines an array of package names that will be bundled when pub‐
769 lishing the package.
770
771 In cases where you need to preserve npm packages locally or have them
772 available through a single file download, you can bundle the packages
773 in a tarball file by specifying the package names in the bundledDepen‐
774 dencies array and executing npm pack.
775
776 For example:
777
778 If we define a package.json like this:
779
780 {
781 "name": "awesome-web-framework",
782 "version": "1.0.0",
783 "bundledDependencies": [
784 "renderized",
785 "super-streams"
786 ]
787 }
788
789 we can obtain awesome-web-framework-1.0.0.tgz file by running npm pack.
790 This file contains the dependencies renderized and super-streams which
791 can be installed in a new project by executing npm install awe‐
792 some-web-framework-1.0.0.tgz. Note that the package names do not in‐
793 clude any versions, as that information is specified in dependencies.
794
795 If this is spelled "bundleDependencies", then that is also honored.
796
797 optionalDependencies
798 If a dependency can be used, but you would like npm to proceed if it
799 cannot be found or fails to install, then you may put it in the option‐
800 alDependencies object. This is a map of package name to version or
801 url, just like the dependencies object. The difference is that build
802 failures do not cause installation to fail. Running npm install
803 --no-optional will prevent these dependencies from being installed.
804
805 It is still your program's responsibility to handle the lack of the de‐
806 pendency. For example, something like this:
807
808 try {
809 var foo = require('foo')
810 var fooVersion = require('foo/package.json').version
811 } catch (er) {
812 foo = null
813 }
814 if ( notGoodFooVersion(fooVersion) ) {
815 foo = null
816 }
817
818 // .. then later in your program ..
819
820 if (foo) {
821 foo.doFooThings()
822 }
823
824 Entries in optionalDependencies will override entries of the same name
825 in dependencies, so it's usually best to only put in one place.
826
827 engines
828 You can specify the version of node that your stuff works on:
829
830 {
831 "engines": {
832 "node": ">=0.10.3 <15"
833 }
834 }
835
836 And, like with dependencies, if you don't specify the version (or if
837 you specify "*" as the version), then any version of node will do.
838
839 You can also use the "engines" field to specify which versions of npm
840 are capable of properly installing your program. For example:
841
842 {
843 "engines": {
844 "npm": "~1.0.20"
845 }
846 }
847
848 Unless the user has set the engine-strict config flag, this field is
849 advisory only and will only produce warnings when your package is in‐
850 stalled as a dependency.
851
852 os
853 You can specify which operating systems your module will run on:
854
855 {
856 "os": [
857 "darwin",
858 "linux"
859 ]
860 }
861
862 You can also block instead of allowing operating systems, just prepend
863 the blocked os with a '!':
864
865 {
866 "os": [
867 "!win32"
868 ]
869 }
870
871 The host operating system is determined by process.platform
872
873 It is allowed to both block and allow an item, although there isn't any
874 good reason to do this.
875
876 cpu
877 If your code only runs on certain cpu architectures, you can specify
878 which ones.
879
880 {
881 "cpu": [
882 "x64",
883 "ia32"
884 ]
885 }
886
887 Like the os option, you can also block architectures:
888
889 {
890 "cpu": [
891 "!arm",
892 "!mips"
893 ]
894 }
895
896 The host architecture is determined by process.arch
897
898 private
899 If you set "private": true in your package.json, then npm will refuse
900 to publish it.
901
902 This is a way to prevent accidental publication of private reposito‐
903 ries. If you would like to ensure that a given package is only ever
904 published to a specific registry (for example, an internal registry),
905 then use the publishConfig dictionary described below to override the
906 registry config param at publish-time.
907
908 publishConfig
909 This is a set of config values that will be used at publish-time. It's
910 especially handy if you want to set the tag, registry or access, so
911 that you can ensure that a given package is not tagged with "latest",
912 published to the global public registry or that a scoped module is pri‐
913 vate by default.
914
915 See npm help config to see the list of config options that can be over‐
916 ridden.
917
918 workspaces
919 The optional workspaces field is an array of file patterns that de‐
920 scribes locations within the local file system that the install client
921 should look up to find each npm help workspace that needs to be sym‐
922 linked to the top level node_modules folder.
923
924 It can describe either the direct paths of the folders to be used as
925 workspaces or it can define globs that will resolve to these same fold‐
926 ers.
927
928 In the following example, all folders located inside the folder ./pack‐
929 ages will be treated as workspaces as long as they have valid pack‐
930 age.json files inside them:
931
932 {
933 "name": "workspace-example",
934 "workspaces": [
935 "./packages/*"
936 ]
937 }
938
939 See npm help workspaces for more examples.
940
941 DEFAULT VALUES
942 npm will default some values based on package contents.
943
944 • "scripts": {"start": "node server.js"} If there is a server.js file
945 in the root of your package, then npm will default the start command
946 to node server.js.
947
948 • "scripts":{"install": "node-gyp rebuild"} If there is a binding.gyp
949 file in the root of your package and you have not defined an install
950 or preinstall script, npm will default the install command to compile
951 using node-gyp.
952
953 • "contributors": [...] If there is an AUTHORS file in the root of
954 your package, npm will treat each line as a Name <email> (url) for‐
955 mat, where email and url are optional. Lines which start with a # or
956 are blank, will be ignored.
957
958
959 SEE ALSO
960 • semver https://github.com/npm/node-semver#versions
961
962 • npm help workspaces
963
964 • npm help init
965
966 • npm help version
967
968 • npm help config
969
970 • npm help help
971
972 • npm help install
973
974 • npm help publish
975
976 • npm help uninstall
977
978
979
980
981 October 2021 PACKAGE.JSON(5)