Minimal CLI Example

The absolute minimum code needed to create a working CLI with Bunli.

Complete Example

// index.ts
import { createCLI } from '@bunli/core'

const cli = createCLI({
  name: 'hello',
  version: '1.0.0',
  description: 'A minimal CLI example'
})

// The CLI automatically includes --help and --version
await cli.run()

That's it! This creates a working CLI with:

--help flag showing usage information
--version flag showing the version
Proper error handling for unknown commands

Running the CLI

# Make it executable
chmod +x ./index.ts

# Run it
./index.ts --help

# Output:
# hello v1.0.0
# A minimal CLI example
#
# Usage: hello [options]
#
# Options:
#   --help     Show help
#   --version  Show version

Adding a Simple Command

Let's add a single command:

// index.ts
import { createCLI, defineCommand } from '@bunli/core'

const cli = createCLI({
  name: 'hello',
  version: '1.0.0',
  description: 'A minimal CLI example'
})

// Add a greet command
cli.command(
  defineCommand({
    name: 'greet',
    description: 'Say hello',
    handler: async () => {
      console.log('Hello, World!')
    }
  })
)

await cli.run()

Usage:

./index.ts greet
# Output: Hello, World!

./index.ts --help
# Now shows the greet command

Command with Options

Add a simple option:

import { createCLI, defineCommand, option } from '@bunli/core'
import { z } from 'zod'

const cli = createCLI({
  name: 'hello',
  version: '1.0.0'
})

cli.command(
  defineCommand({
    name: 'greet',
    description: 'Greet someone',
    options: {
      name: option(
        z.string().default('World'),
        { description: 'Name to greet' }
      )
    },
    handler: async ({ flags }) => {
      console.log(`Hello, ${flags.name}!`)
    }
  })
)

await cli.run()

Usage:

./index.ts greet
# Output: Hello, World!

./index.ts greet --name Alice
# Output: Hello, Alice!

With Package.json

For a more complete setup:

{
  "name": "hello-cli",
  "version": "1.0.0",
  "type": "module",
  "bin": {
    "hello": "./index.ts"
  },
  "dependencies": {
    "@bunli/core": "latest",
    "zod": "^3.0.0"
  }
}

// index.ts
#!/usr/bin/env bun
import { createCLI } from '@bunli/core'
import { name, version, description } from './package.json'

const cli = createCLI({
  name,
  version,
  description
})

await cli.run()

Install globally:

bun link
# Now use anywhere
hello --version

Even More Minimal

The absolute bare minimum:

#!/usr/bin/env bun
import { createCLI } from '@bunli/core'

await createCLI({ name: 'hi' }).run()

This 3-line CLI still has:

Argument parsing
Help generation
Error handling

Building for Distribution

Build the minimal CLI:

# Development
bun run index.ts

# Build for production
bunli build --compile

# Now you have a standalone executable
./dist/hello --help

Key Takeaways

Minimal Setup: Just a few lines to get started
Automatic Features: Help, version, and error handling built-in
Type Safety: Full TypeScript support out of the box
Zero Config: Works without any configuration files
Production Ready: Can be compiled to standalone binary

Next Steps

Multi-Command Example - Add multiple commands
Getting Started Guide - Step-by-step tutorial
API Reference - Complete API documentation

Minimal CLI

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