NPX(1)                                                             User Commands                                                            NPX(1)

NAME

       npx - execute npm package binaries

SYNOPSIS

       npx [options] <command>[@version] [command-arg]...

       npx [options] [-p|--package <pkg>]... <command> [command-arg]...

       npx [options] -c '<command-string>'

       npx --shell-auto-fallback [shell]

INSTALL

       npm install -g npx

DESCRIPTION

       Executes <command> either from a local node_modules/.bin, or from a central cache, installing any packages needed in order for <command> to
       run.

       By default, npx will check whether <command> exists in $PATH, or in the local project binaries, and  execute  that.  If  <command>  is  not
       found, it will be installed prior to execution.

       Unless  a  --package  option  is specified, npx will try to guess the name of the binary to invoke depending on the specifier provided. All
       package specifiers understood by npm may be used with npx, including git specifiers, remote tarballs, local directories,  or  scoped  pack-
       ages.

       If  a  full specifier is included, or if --package is used, npx will always use a freshly-installed, temporary version of the package. This
       can also be forced with the --ignore-existing flag.

       o -p, --package <package> - define the package to be installed. This defaults to the value of <command>. This is only needed  for  packages
         with  multiple  binaries  if  you want to call one of the other executables, or where the binary name does not match the package name. If
         this option is provided <command> will be executed as-is, without interpreting @version if it's there. Multiple --package options may  be
         provided, and all the packages specified will be installed.

       o --no-install  -  If  passed  to  npx,  it will only try to run <command> if it already exists in the current path or in $prefix/node_mod-
         ules/.bin. It won't try to install missing commands.

       o --cache <path> - set the location of the npm cache. Defaults to npm's own cache settings.

       o --userconfig <path> - path to the user configuration file to pass to npm. Defaults to whatever npm's current default is.

       o -c <string> - Execute <string> inside an npm run-script-like shell environment, with all the usual environment variables available.  Only
         the first item in <string> will be automatically used as <command>. Any others must use -p.

       o --shell <string> - The shell to invoke the command with, if any.

       o --shell-auto-fallback  [<shell>]  -  Generates  shell  code to override your shell's "command not found" handler with one that calls npx.
         Tries to figure out your shell, or you can pass its name (either bash, fish, or zsh) as an option. See below for how to install.

       o --ignore-existing - If this flag is set, npx will not look in $PATH, or in the current package's node_modules/.bin for an  existing  ver-
         sion before deciding whether to install. Binaries in those paths will still be available for execution, but will be shadowed by any pack-
         ages requested by this install.

       o -q, --quiet - Suppressed any output from npx itself (progress bars, error messages, install reports). Subcommand output itself  will  not
         be silenced.

       o -n,  --node-arg  -  Extra  node argument to supply to node when binary is a node script. You can supply this option multiple times to add
         more arguments.

       o -v, --version - Show the current npx version.

EXAMPLES

   Running a project-local bin
         $ npm i -D webpack
         $ npx webpack ...

   One-off invocation without local installation
         $ npm rm webpack
         $ npx webpack -- ...
         $ cat package.json
         ...webpack not in "devDependencies"...

   Invoking a command from a github repository
         $ npx github:piuccio/cowsay
         ...or...
         $ npx git+ssh://my.hosted.git:cowsay.git#semver:^1
         ...etc...

   Execute a full shell command using one npx call w/ multiple packages
         $ npx -p lolcatjs -p cowsay -c 
           'echo "$npm_package_name@$npm_package_version" | cowsay | lolcatjs'
         ...
          _____
         < your-cool-package@1.2.3 >
          -----
                    ^__^
                    (oo)\_______
                     (__)       )/
                         ||----w |
                         ||     ||

   Run node binary with --inspect
         $ npx --node-arg=--inspect cowsay
         Debugger listening on ws://127.0.0.1:9229/....

   Specify a node version to run npm scripts (or anything else!)
         npx -p node@8 npm run build

SHELL AUTO FALLBACK

       You can configure npx to run as your default fallback command when you type something in the command line with an @ but the command is  not
       found. This includes installing packages that were not found in the local prefix either.

       For example:

         $ npm@4 --version
         (stderr) npm@4 not found. Trying with npx...
         4.6.1
         $ asdfasdfasf
         zsh: command not found: asfdasdfasdf

       Currently, zsh, bash (>= 4), and fish are supported. You can access these completion scripts using npx --shell-auto-fallback <shell>.

       To  install permanently, add the relevant line below to your ~/.bashrc, ~/.zshrc, ~/.config/fish/config.fish, or as needed. To install just
       for the shell session, simply run the line.

       You can optionally pass through --no-install when generating the fallback to prevent it from installing packages if the command is missing.

   For bash@>=4:
         $ source <(npx --shell-auto-fallback bash)

   For zsh:
         $ source <(npx --shell-auto-fallback zsh)

   For fish:
         $ source (npx --shell-auto-fallback fish | psub)

ACKNOWLEDGEMENTS

       Huge thanks to Kwyn Meagher https://blog.kwyn.io for generously donating the package name in the main npm registry. Previously npx was used
       for a Tessel board Neopixels library, which can now be found under npx-tessel https://npm.im/npx-tessel.

AUTHOR

       Written by Kat Marchan https://github.com/zkat.

REPORTING BUGS

       Please file any relevant issues on Github. https://github.com/zkat/npx

LICENSE

       This work is released by its authors into the public domain under CC0-1.0. See LICENSE.md for details.

SEE ALSO

       o npm(1)

       o npm-run-script(1)

       o npm-config(7)

npx@10.1.1                                                          April 2018                                                              NPX(1)