1NPX(1)                                                                  NPX(1)
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NAME

6       npx - Run a command from a local or remote npm package
7
8   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
14         npx <pkg>[@<specifier>] [args...]
15         npx -p <pkg>[@<specifier>] <cmd> [args...]
16         npx -c '<cmd> [args...]'
17         npx -p <pkg>[@<specifier>] -c '<cmd> [args...]'
18
19         alias: npm x, npx
20
21         --package=<pkg> (may be specified multiple times)
22         -p is a shorthand for --package only when using npx executable
23         -c <cmd> --call=<cmd> (may not be mixed with positional arguments)
24
25   Description
26       This command allows you to run an arbitrary command from an npm package
27       (either one installed locally, or fetched remotely), in a similar  con‐
28       text as running it via npm run.
29
30       Whatever  packages  are  specified by the --package option will be pro‐
31       vided in the PATH of the executed command, along with any  locally  in‐
32       stalled  package  executables.   The  --package option may be specified
33       multiple times, to execute the supplied command in an environment where
34       all specified packages are available.
35
36       If  any  requested packages are not present in the local project depen‐
37       dencies, then they are installed to a folder in the npm cache, which is
38       added  to  the  PATH  environment  variable in the executed process.  A
39       prompt is printed (which can be suppressed by providing either --yes or
40       --no).
41
42       Package  names  provided without a specifier will be matched with what‐
43       ever version exists in the local project.  Package names with a  speci‐
44       fier  will  only be considered a match if they have the exact same name
45       and version as the local dependency.
46
47       If no -c or --call option is provided, then  the  positional  arguments
48       are  used  to generate the command string.  If no --package options are
49       provided, then npm will attempt to determine the executable  name  from
50       the package specifier provided as the first positional argument accord‐
51       ing to the following heuristic:
52
53       • If the package has a single entry in its bin field  in  package.json,
54         or  if all entries are aliases of the same command, then that command
55         will be used.
56
57       • If the package has multiple bin entries, and one of them matches  the
58         unscoped portion of the name field, then that command will be used.
59
60       • If  this  does not result in exactly one option (either because there
61         are no bin entries, or none of them match the name of  the  package),
62         then npm exec exits with an error.
63
64
65       To  run  a  binary  other  than  the  named binary, specify one or more
66       --package options, which will prevent npm from  inferring  the  package
67       from the first command argument.
68
69   npx vs npm exec
70       When run via the npx binary, all flags and options must be set prior to
71       any positional arguments.  When run via npm exec,  a  double-hyphen  --
72       flag can be used to suppress npm's parsing of switches and options that
73       should be sent to the executed command.
74
75       For example:
76
77         $ npx foo@latest bar --package=@npmcli/foo
78
79       In this case, npm will resolve the foo package name, and run  the  fol‐
80       lowing command:
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82         $ foo bar --package=@npmcli/foo
83
84       Since  the --package option comes after the positional arguments, it is
85       treated as an argument to the executed command.
86
87       In contrast, due to npm's argument parsing logic, running this  command
88       is different:
89
90         $ npm exec foo@latest bar --package=@npmcli/foo
91
92       In  this case, npm will parse the --package option first, resolving the
93       @npmcli/foo package.  Then, it will execute the  following  command  in
94       that context:
95
96         $ foo@latest bar
97
98       The  double-hyphen  character  is recommended to explicitly tell npm to
99       stop parsing command line options and switches.  The following  command
100       would thus be equivalent to the npx command above:
101
102         $ npm exec -- foo@latest bar --package=@npmcli/foo
103
104   Examples
105       Run the version of tap in the local dependencies, with the provided ar‐
106       guments:
107
108         $ npm exec -- tap --bail test/foo.js
109         $ npx tap --bail test/foo.js
110
111       Run a command other than the command whose  name  matches  the  package
112       name by specifying a --package option:
113
114         $ npm exec --package=foo -- bar --bar-argument
115         # ~ or ~
116         $ npx --package=foo bar --bar-argument
117
118       Run an arbitrary shell script, in the context of the current project:
119
120         $ npm x -c 'eslint && say "hooray, lint passed"'
121         $ npx -c 'eslint && say "hooray, lint passed"'
122
123   Compatibility with Older npx Versions
124       The  npx  binary  was  rewritten  in npm v7.0.0, and the standalone npx
125       package deprecated at that time.  npx uses the npm exec command instead
126       of  a  separate  argument  parser and install process, with some affor‐
127       dances to maintain backwards compatibility with the  arguments  it  ac‐
128       cepted in previous versions.
129
130       This resulted in some shifts in its functionality:
131
132       • Any npm config value may be provided.
133
134       • To prevent security and user-experience problems from mistyping pack‐
135         age names, npx prompts before  installing  anything.   Suppress  this
136         prompt with the -y or --yes option.
137
138       • The --no-install option is deprecated, and will be converted to --no.
139
140       • Shell fallback functionality is removed, as it is not advisable.
141
142       • The  -p argument is a shorthand for --parseable in npm, but shorthand
143         for --package in npx.  This is maintained, but only for the npx  exe‐
144         cutable.
145
146       • The  --ignore-existing option is removed.  Locally installed bins are
147         always present in the executed process PATH.
148
149       • The --npm option is removed.  npx will always use the  npm  it  ships
150         with.
151
152       • The --node-arg and -n options are removed.
153
154       • The --always-spawn option is redundant, and thus removed.
155
156       • The --shell option is replaced with --script-shell, but maintained in
157         the npx executable for backwards compatibility.
158
159
160   See Also
161       • npm help run-script
162
163       • npm help scripts
164
165       • npm help test
166
167       • npm help start
168
169       • npm help restart
170
171       • npm help stop
172
173       • npm help config
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178                                 October 2021                           NPX(1)
Impressum