Building CLI Tools with Node.js

Build Tools People Actually Use

Good CLI tools save time and reduce errors.

Project Setup

mkdir my-cli && cd my-cli
npm init -y
npm install commander inquirer chalk

// package.json
{
  "bin": {
    "my-cli": "./index.js"
  }
}

Basic Structure

#!/usr/bin/env node
const { program } = require('commander');

program
    .name('my-cli')
    .version('1.0.0')
    .description('My awesome CLI tool');

program
    .command('greet <name>')
    .description('Greet someone')
    .option('-l, --loud', 'Shout the greeting')
    .action((name, options) => {
        const greeting = `Hello, ${name}!`;
        console.log(options.loud ? greeting.toUpperCase() : greeting);
    });

program.parse();

Interactive Prompts

const inquirer = require('inquirer');

async function setup() {
    const answers = await inquirer.prompt([
        {
            type: 'input',
            name: 'projectName',
            message: 'Project name:',
            default: 'my-project'
        },
        {
            type: 'list',
            name: 'template',
            message: 'Choose a template:',
            choices: ['basic', 'advanced', 'minimal']
        },
        {
            type: 'confirm',
            name: 'typescript',
            message: 'Use TypeScript?',
            default: true
        }
    ]);

    console.log('Creating project:', answers);
}

Colorful Output

const chalk = require('chalk');

console.log(chalk.green('✓ Success!'));
console.log(chalk.red('✗ Error!'));
console.log(chalk.yellow('⚠ Warning'));
console.log(chalk.blue.bold('Info'));

Publishing

# Link for local testing
npm link

# Publish to npm
npm publish

Tips

• Provide --help automatically (commander does this)
• Use exit codes (0 success, 1 error)
• Support --quiet and --verbose
• Handle Ctrl+C gracefully