@rcompat/args

Runtime-agnostic access to command-line arguments.

What is @rcompat/args?

A cross-runtime module that provides consistent access to program arguments across Node, Deno, and Bun. Write your CLI tools once and run them on any JavaScript runtime.

Installation

npm install @rcompat/args

Usage

import args from "@rcompat/args";

// args is a string[] containing your program arguments
console.log(args);

Running node app.js foo bar --verbose will output

[ 'foo', 'bar', '--verbose' ]

Example: Simple CLI

import args from "@rcompat/args";

const [command, ...rest] = args;

switch (command) {
    case "greet":
        console.log(`Hello, ${rest[0] ?? "world"}!`);
        break;

    case "help":
        console.log(
            `Usage:
  app.js <command> [args]

Commands:
  greet [name]   Greet the specified name (or 'world')
  help           Show this help message`
        );
        break;

    default:
        console.log("Usage: app.js <command> [args]");
}

node app.js greet Bob # Hello, Bob!
bun app.js greet      # Hello, world!

How It Works

Different runtimes expose command-line arguments differently:

| Runtime | Source | Includes runtime/script? | | ------- | -------------- | ------------------------ | | Node | process.argv | Yes (first two elements) | | Bun | Bun.argv | Yes (first two elements) | | Deno | Deno.args | No |

@rcompat/args normalizes this by always returning only your program's arguments — the runtime executable and script path are stripped away.

The package uses runtime keys to select the appropriate implementation at import time, with zero runtime overhead.

Cross-Runtime Compatibility

| Runtime | Supported | | ------- | --------- | | Node.js | ✓ | | Deno | ✓ | | Bun | ✓ |

No configuration required — just import and use.

License

MIT

Contributing

See CONTRIBUTING.md in the repository root.