1NPM-EXEC(1) NPM-EXEC(1)
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6 npm-exec - Run a command from a local or remote npm package
7 Synopsis
9 npm exec -- <pkg>[@<version>] [args...]
10 npm exec --package=<pkg>[@<version>] -- <cmd> [args...]
11 npm exec -c '<cmd> [args...]'
12 npm exec --package=foo -c '<cmd> [args...]'
13 alias: x
15 Description
17 This command allows you to run an arbitrary command from an npm package
18 (either one installed locally, or fetched remotely), in a similar con‐
19 text as running it via npm run.
20 Run without positional arguments or --call, this allows you to interac‐
22 tively run commands in the same sort of shell environment that pack‐
23 age.json scripts are run. Interactive mode is not supported in CI envi‐
24 ronments when standard input is a TTY, to prevent hangs.
25 Whatever packages are specified by the --package option will be pro‐
27 vided in the PATH of the executed command, along with any locally in‐
28 stalled package executables. The --package option may be specified mul‐
29 tiple times, to execute the supplied command in an environment where
30 all specified packages are available.
31 If any requested packages are not present in the local project depen‐
33 dencies, then a prompt is printed, which can be suppressed by providing
34 either --yes or --no. When standard input is not a TTY or a CI environ‐
35 ment is detected, --yes is assumed. The requested packages are in‐
36 stalled to a folder in the npm cache, which is added to the PATH envi‐
37 ronment variable in the executed process.
38 Package names provided without a specifier will be matched with what‐
40 ever version exists in the local project. Package names with a speci‐
41 fier will only be considered a match if they have the exact same name
42 and version as the local dependency.
43 If no -c or --call option is provided, then the positional arguments
45 are used to generate the command string. If no --package options are
46 provided, then npm will attempt to determine the executable name from
47 the package specifier provided as the first positional argument accord‐
48 ing to the following heuristic:
49 • If the package has a single entry in its bin field in package.json,
51 or if all entries are aliases of the same command, then that com‐
52 mand will be used.
53 • If the package has multiple bin entries, and one of them matches
55 the unscoped portion of the name field, then that command will be
56 used.
57 • If this does not result in exactly one option (either because there
59 are no bin entries, or none of them match the name of the package),
60 then npm exec exits with an error.
61 To run a binary other than the named binary, specify one or more
64 --package options, which will prevent npm from inferring the package
65 from the first command argument.
66 npx vs npm exec
68 When run via the npx binary, all flags and options must be set prior to
69 any positional arguments. When run via npm exec, a double-hyphen --
70 flag can be used to suppress npm's parsing of switches and options that
71 should be sent to the executed command.
72 For example:
74 $ npx foo@latest bar --package=@npmcli/foo
76 In this case, npm will resolve the foo package name, and run the fol‐
78 lowing command:
79 $ foo bar --package=@npmcli/foo
81 Since the --package option comes after the positional arguments, it is
83 treated as an argument to the executed command.
84 In contrast, due to npm's argument parsing logic, running this command
86 is different:
87 $ npm exec foo@latest bar --package=@npmcli/foo
89 In this case, npm will parse the --package option first, resolving the
91 @npmcli/foo package. Then, it will execute the following command in
92 that context:
93 $ foo@latest bar
95 The double-hyphen character is recommended to explicitly tell npm to
97 stop parsing command line options and switches. The following command
98 would thus be equivalent to the npx command above:
99 $ npm exec -- foo@latest bar --package=@npmcli/foo
101 Configuration
103 package
104 • Default:
105 • Type: String (can be set multiple times)
107 The package or packages to install for npm help exec
110 call
112 • Default: ""
113 • Type: String
115 Optional companion option for npm exec, npx that allows for specifying
118 a custom command to be run along with the installed packages.
119 npm exec --package yo --package generator-node --call "yo node"
121 workspace
123 • Default:
124 • Type: String (can be set multiple times)
126 Enable running a command in the context of the configured workspaces of
129 the current project while filtering by running only the workspaces de‐
130 fined by this configuration option.
131 Valid values for the workspace config are either:
133 • Workspace names
135 • Path to a workspace directory
137 • Path to a parent workspace directory (will result in selecting all
139 workspaces within that folder)
140 When set for the npm init command, this may be set to the folder of a
143 workspace which does not yet exist, to create the folder and set it up
144 as a brand new workspace within the project.
145 This value is not exported to the environment for child processes.
147 workspaces
149 • Default: null
150 • Type: null or Boolean
152 Set to true to run the command in the context of all configured
155 workspaces.
156 Explicitly setting this to false will cause commands like install to
158 ignore workspaces altogether. When not set explicitly:
159 • Commands that operate on the node_modules tree (install, update,
161 etc.) will link workspaces into the node_modules folder. - Commands
162 that do other things (test, exec, publish, etc.) will operate on
163 the root project, unless one or more workspaces are specified in
164 the workspace config.
165 This value is not exported to the environment for child processes.
168 include-workspace-root
170 • Default: false
171 • Type: Boolean
173 Include the workspace root when workspaces are enabled for a command.
176 When false, specifying individual workspaces via the workspace config,
178 or all workspaces via the workspaces flag, will cause npm to operate
179 only on the specified workspaces, and not on the root project.
180 This value is not exported to the environment for child processes.
182 Examples
184 Run the version of tap in the local dependencies, with the provided ar‐
185 guments:
186 $ npm exec -- tap --bail test/foo.js
188 $ npx tap --bail test/foo.js
189 Run a command other than the command whose name matches the package
191 name by specifying a --package option:
192 $ npm exec --package=foo -- bar --bar-argument
194 # ~ or ~
195 $ npx --package=foo bar --bar-argument
196 Run an arbitrary shell script, in the context of the current project:
198 $ npm x -c 'eslint && say "hooray, lint passed"'
200 $ npx -c 'eslint && say "hooray, lint passed"'
201 Workspaces support
203 You may use the workspace ⟨/using-npm/config#workspace⟩ or workspaces
204 ⟨/using-npm/config#workspaces⟩ configs in order to run an arbitrary
205 command from an npm package (either one installed locally, or fetched
206 remotely) in the context of the specified workspaces. If no positional
207 argument or --call option is provided, it will open an interactive sub‐
208 shell in the context of each of these configured workspaces one at a
209 time.
210 Given a project with configured workspaces, e.g:
212 +-- package.json
214 `-- packages
215 +-- a
216 | `-- package.json
217 +-- b
218 | `-- package.json
219 `-- c
220 `-- package.json
221 Assuming the workspace configuration is properly set up at the root
223 level package.json file. e.g:
224 {
226 "workspaces": [ "./packages/*" ]
227 }
228 You can execute an arbitrary command from a package in the context of
230 each of the configured workspaces when using the workspaces config op‐
231 tions ⟨/using-npm/config#workspace⟩, in this example we're using eslint
232 to lint any js file found within each workspace folder:
233 npm exec --ws -- eslint ./*.js
235 Filtering workspaces
237 It's also possible to execute a command in a single workspace using the
238 workspace config along with a name or directory path:
239 npm exec --workspace=a -- eslint ./*.js
241 The workspace config can also be specified multiple times in order to
243 run a specific script in the context of multiple workspaces. When
244 defining values for the workspace config in the command line, it also
245 possible to use -w as a shorthand, e.g:
246 npm exec -w a -w b -- eslint ./*.js
248 This last command will run the eslint command in both ./packages/a and
250 ./packages/b folders.
251 Compatibility with Older npx Versions
253 The npx binary was rewritten in npm v7.0.0, and the standalone npx
254 package deprecated at that time. npx uses the npm exec command instead
255 of a separate argument parser and install process, with some affor‐
256 dances to maintain backwards compatibility with the arguments it ac‐
257 cepted in previous versions.
258 This resulted in some shifts in its functionality:
260 • Any npm config value may be provided.
262 • To prevent security and user-experience problems from mistyping
264 package names, npx prompts before installing anything. Suppress
265 this prompt with the -y or --yes option.
266 • The --no-install option is deprecated, and will be converted to
268 --no.
269 • Shell fallback functionality is removed, as it is not advisable.
271 • The -p argument is a shorthand for --parseable in npm, but short‐
273 hand for --package in npx. This is maintained, but only for the npx
274 executable.
275 • The --ignore-existing option is removed. Locally installed bins are
277 always present in the executed process PATH.
278 • The --npm option is removed. npx will always use the npm it ships
280 with.
281 • The --node-arg and -n options are removed.
283 • The --always-spawn option is redundant, and thus removed.
285 • The --shell option is replaced with --script-shell, but maintained
287 in the npx executable for backwards compatibility.
288 A note on caching
291 The npm cli utilizes its internal package cache when using the package
292 name specified. You can use the following to change how and when the
293 cli uses this cache. See npm help cache for more on how the cache
294 works.
295 prefer-online
297 Forces staleness checks for packages, making the cli look for updates
298 immediately even if the package is already in the cache.
299 prefer-offline
301 Bypasses staleness checks for packages. Missing data will still be re‐
302 quested from the server. To force full offline mode, use offline.
303 offline
305 Forces full offline mode. Any packages not locally cached will result
306 in an error.
307 workspace
309 • Default:
310 • Type: String (can be set multiple times)
312 Enable running a command in the context of the configured workspaces of
315 the current project while filtering by running only the workspaces de‐
316 fined by this configuration option.
317 Valid values for the workspace config are either:
319 • Workspace names
321 • Path to a workspace directory
323 • Path to a parent workspace directory (will result to selecting all
325 of the nested workspaces)
326 This value is not exported to the environment for child processes.
329 workspaces
331 • Alias: --ws
332 • Type: Boolean
334 • Default: false
336 Run scripts in the context of all configured workspaces for the current
339 project.
340 See Also
342 • npm help run-script
343 • npm help scripts
345 • npm help test
347 • npm help start
349 • npm help restart
351 • npm help stop
353 • npm help config
355 • npm help workspaces
357 • npm help npx
359 November 2023 NPM-EXEC(1)