NPX(1) | User Commands | NPX(1) |
npx - execute npm package binaries
npx [options] <command>[@version] [command-arg]...
npx [options] [-p|--package <pkg>]... <command> [command-arg]...
npx [options] -c '<command-string>'
npx --shell-auto-fallback [shell]
npm install -g npx
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 packages.
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.
$ npm i -D webpack $ npx webpack ...
$ npm rm webpack $ npx webpack -- ... $ cat package.json ...webpack not in "devDependencies"...
$ npx github:piuccio/cowsay ...or... $ npx git+ssh://my.hosted.git:cowsay.git#semver:^1 ...etc...
$ npx -p lolcatjs -p cowsay -c \
'echo "$npm_package_name@$npm_package_version" | cowsay | lolcatjs' ...
_____ < your-cool-package@1.2.3 >
-----
\ ^__^
\ (oo)\_______
(__)\ )\/\
||----w |
|| ||
$ npx --node-arg=--inspect cowsay Debugger listening on ws://127.0.0.1:9229/....
npx -p node@8 npm run build
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.
$ source <(npx --shell-auto-fallback bash)
$ source <(npx --shell-auto-fallback zsh)
$ source (npx --shell-auto-fallback fish | psub)
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.
Written by Kat Marchan https://github.com/zkat.
Please file any relevant issues on Github. https://github.com/zkat/npx
This work is released by its authors into the public domain under CC0-1.0. See LICENSE.md for details.
February 2019 | npx@10.2.0+repack-1 |