Run package binaries with bunx

Some npm packages provide command-line tools. bunx finds and runs those tools.

For example, run Prettier without installing it globally:

bunx prettier --check .

bunx first looks for the executable in the project’s installed packages. If it is missing, Bun downloads the package into a shared cache and runs it.

This is similar to npx.

Prefer local versions for project tools

A formatter used by a team should have a version recorded by the project:

bun add --dev prettier

Add a script to package.json:

{
  "scripts": {
    "format": "prettier --write .",
    "format:check": "prettier --check ."
  }
}

Now everyone runs the same installed version:

bun run format:check

Use bunx directly for temporary commands, project generators, or tools you are evaluating. Use a local development dependency for commands that belong to the project’s normal workflow.

Choose the runtime deliberately

Many package binaries start with a Node.js shebang. bunx respects it and uses Node.js.

You can force Bun with --bun:

bunx --bun vite --version

Do this only when you intend to test the tool under Bun. A command working through ordinary bunx does not prove the package itself ran on the Bun runtime.