jarle bunx
Run packages from npm
bunx is an alias for bun x. The bunx CLI will be auto-installed when you install bun.
Use bunx to auto-install and run packages from npm. It's Bun's equivalent of npx or yarn dlx.
bunx cowsay "Hello world!"
Packages can declare executables in the "bin" field of their package.json. These are known as package executables or package binaries.
{
// ... other fields
"name": "my-cli",
"bin": {
"my-cli": "dist/index.js"
}
}
These executables are commonly plain JavaScript files marked with a shebang line to indicate which program should be used to execute them. The following file indicates that it should be executed with node.
#!/usr/bin/env node
console.log("Hello world!");
These executables can be run with bunx,
bunx my-cli
As with npx, bunx will check for a locally installed package first, then fall back to auto-installing the package from npm. Installed packages will be stored in Bun's global cache for future use.
Arguments and flags
To pass additional command-line flags and arguments through to the executable, place them after the executable name.
bunx my-cli --foo bar
Shebangs
By default, Bun respects shebangs. If an executable is marked with #!/usr/bin/env node, Bun will spin up a node process to execute the file. However, in some cases it may be desirable to run executables using Bun's runtime, even if the executable indicates otherwise. To do so, include the --bun flag.
bunx --bun my-cli
The --bun flag must occur before the executable name. Flags that appear after the name are passed through to the executable.
bunx --bun my-cli # good
bunx my-cli --bun # bad
Package flag
--package <pkg> or -p <pkg> - Run binary from specific package. Useful when binary name differs from package name:
bunx -p renovate renovate-config-validator
bunx --package @angular/cli ng
To force bun to always be used with a script, use a shebang.
#!/usr/bin/env bun
Usage
bunx [flags] <package>[@version] [flags and arguments for the package]
Execute an npm package executable (CLI), automatically installing into a global shared cache if not installed in node_modules.
Flags
Examples
# Run Prisma migrations
bunx prisma migrate
# Format a file with Prettier
bunx prettier foo.js
# Run a specific version of a package
bunx uglify-js@3.14.0 app.js
# Use --package when binary name differs from package name
bunx -p @angular/cli ng new my-app
# Force running with Bun instead of Node.js, even if the executable contains a Node shebang
bunx --bun vite dev foo.js