Browserify Cheat Sheet

Browserify - Browser-side require()

Browserify ti permette di utilizzare require('modules') nel browser raggruppando tutte le tue dipendenze. Utilizza lo stesso sistema di moduli di Node.js, consentendoti di utilizzare moduli npm nel browser e organizzare il tuo codice con moduli CommonJS.

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Install Browserify globally

npm install -g browserify

Verify installation

browserify —version


### Local Installation (Recommended)
```bash
# Initialize npm project
npm init -y

# Install Browserify locally
npm install --save-dev browserify

# Install common transforms
npm install --save-dev babelify uglifyify envify

Project Setup

# Create project structure
mkdir my-browserify-project
cd my-browserify-project

# Initialize package.json
npm init -y

# Install Browserify and dependencies
npm install --save-dev browserify babelify @babel/core @babel/preset-env

# Create source directories
mkdir -p src/{js,css}
mkdir dist

# Create entry point
touch src/js/main.js

Package.json Scripts

{
  "name": "my-browserify-project",
  "version": "1.0.0",
  "scripts": {
    "build": "browserify src/js/main.js -o dist/bundle.js",
    "build:watch": "watchify src/js/main.js -o dist/bundle.js -v",
    "build:prod": "browserify src/js/main.js -t [ babelify --presets [ @babel/preset-env ] ] -t uglifyify -o dist/bundle.min.js",
    "dev": "budo src/js/main.js:bundle.js --live --open",
    "test": "tape test/*.js | tap-spec"
  },
  "browserify": {
    "transform": [
      ["babelify", {
        "presets": ["@babel/preset-env"]
      }]
    ]
  }
}

Getting Started

Basic Module Structure

// src/js/math.js - A simple module
function add(a, b) {
  return a + b;
}

function multiply(a, b) {
  return a * b;
}

function subtract(a, b) {
  return a - b;
}

// Export functions
module.exports = {
  add: add,
  multiply: multiply,
  subtract: subtract
};

// Or using shorthand
module.exports = { add, multiply, subtract };

// src/js/utils.js - Utility functions
const capitalize = (str) => {
  return str.charAt(0).toUpperCase() + str.slice(1);
};

const formatDate = (date) => {
  return date.toLocaleDateString();
};

const debounce = (func, wait) => {
  let timeout;
  return function executedFunction(...args) {
    const later = () => {
      clearTimeout(timeout);
      func(...args);
    };
    clearTimeout(timeout);
    timeout = setTimeout(later, wait);
  };
};

module.exports = {
  capitalize,
  formatDate,
  debounce
};

Main Entry Point

// src/js/main.js - Application entry point
const math = require('./math');
const utils = require('./utils');
const $ = require('jquery'); // npm module

// Use local modules
console.log('2 + 3 =', math.add(2, 3));
console.log('4 * 5 =', math.multiply(4, 5));

// Use utility functions
const title = utils.capitalize('hello world');
console.log('Capitalized:', title);

// Use npm modules
$(document).ready(function() {
  $('body').append('<h1>' + title + '</h1>');
  
  // Add some interactivity
  $('h1').click(function() {
    $(this).css('color', 'blue');
  });
});

// Export for testing
if (typeof module !== 'undefined' && module.exports) {
  module.exports = { math, utils };
}

HTML Integration

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Browserify Demo</title>
</head>
<body>
    <div id="app">
        <h2>Browserify Application</h2>
        <button id="calculate">Calculate</button>
        <div id="result"></div>
    </div>
    
    <!-- Include the bundled JavaScript -->
    <script src="dist/bundle.js"></script>
</body>
</html>

Basic Usage

Simple Bundle Creation

# Basic bundling
browserify src/js/main.js -o dist/bundle.js

# Bundle with verbose output
browserify src/js/main.js -o dist/bundle.js -v

# Bundle to stdout
browserify src/js/main.js

# Bundle multiple entry points
browserify src/js/main.js src/js/admin.js -o dist/bundle.js

Using Transforms

# Bundle with Babel transform
browserify src/js/main.js -t babelify -o dist/bundle.js

# Bundle with multiple transforms
browserify src/js/main.js -t babelify -t uglifyify -o dist/bundle.js

# Transform with options
browserify src/js/main.js -t [ babelify --presets [ @babel/preset-env ] ] -o dist/bundle.js

Watch Mode

# Install watchify
npm install --save-dev watchify

# Watch for changes
watchify src/js/main.js -o dist/bundle.js -v

# Watch with transforms
watchify src/js/main.js -t babelify -o dist/bundle.js -v

# Watch with polling (for network drives)
watchify src/js/main.js -o dist/bundle.js -v --poll

Command Line Interface

Basic Commands

# Bundle a file
browserify input.js -o output.js

# Bundle to stdout
browserify input.js > output.js

# Bundle with debug info
browserify input.js -d -o output.js

# Bundle with standalone UMD
browserify input.js -s MyModule -o output.js

Advanced Options

# Exclude modules
browserify input.js -x jquery -o output.js

# External dependencies
browserify input.js --external jquery -o output.js

# Ignore modules
browserify input.js --ignore fs -o output.js

# Insert global variables
browserify input.js --insert-globals -o output.js

# Detect globals
browserify input.js --detect-globals -o output.js

Transform Options

# Apply transforms
browserify input.js -t babelify -o output.js

# Transform with configuration
browserify input.js -t [ babelify --presets [ @babel/preset-env ] ] -o output.js

# Global transforms (apply to node_modules)
browserify input.js -g uglifyify -o output.js

# List available transforms
npm search browserify-transform

Plugin Options

# Use plugins
browserify input.js -p [ factor-bundle -o bundle1.js -o bundle2.js ] -o common.js

# Plugin with options
browserify input.js -p [ browserify-shim ] -o output.js

# Multiple plugins
browserify input.js -p plugin1 -p plugin2 -o output.js

Programmatic API

Basic API Usage

// build.js - Build script using Browserify API
const browserify = require('browserify');
const fs = require('fs');

// Create browserify instance
const b = browserify({
  entries: ['src/js/main.js'],
  debug: true // Enable source maps
});

// Add transforms
b.transform('babelify', {
  presets: ['@babel/preset-env']
});

// Bundle and write to file
b.bundle()
  .pipe(fs.createWriteStream('dist/bundle.js'))
  .on('finish', () => {
    console.log('Bundle created successfully!');
  })
  .on('error', (err) => {
    console.error('Bundle error:', err);
  });

Advanced API Configuration

const browserify = require('browserify');
const fs = require('fs');
const path = require('path');

// Advanced configuration
const b = browserify({
  entries: ['src/js/main.js'],
  debug: process.env.NODE_ENV !== 'production',
  cache: {},
  packageCache: {},
  fullPaths: false,
  
  // Transform options
  transform: [
    ['babelify', {
      presets: ['@babel/preset-env'],
      sourceMaps: true
    }]
  ],
  
  // Plugin options
  plugin: [
    ['factor-bundle', {
      outputs: ['dist/page1.js', 'dist/page2.js']
    }]
  ]
});

// Add external dependencies
b.external(['jquery', 'lodash']);

// Add ignore patterns
b.ignore('fs');
b.ignore('path');

// Bundle with error handling
function bundle() {
  return b.bundle()
    .on('error', function(err) {
      console.error('Browserify error:', err.message);
      this.emit('end');
    })
    .pipe(fs.createWriteStream('dist/bundle.js'));
}

// Initial bundle
bundle();

// Watch for changes (if using watchify)
if (process.env.NODE_ENV === 'development') {
  const watchify = require('watchify');
  const w = watchify(b);
  
  w.on('update', () => {
    console.log('Rebuilding...');
    bundle();
  });
  
  w.on('log', (msg) => {
    console.log(msg);
  });
}

Stream Processing

const browserify = require('browserify');
const through2 = require('through2');
const uglify = require('uglify-js');

// Custom stream processing
function createBundle() {
  const b = browserify('src/js/main.js');
  
  return b.bundle()
    .pipe(through2(function(chunk, enc, callback) {
      // Custom processing
      let code = chunk.toString();
      
      // Minify in production
      if (process.env.NODE_ENV === 'production') {
        const result = uglify.minify(code);
        code = result.code;
      }
      
      this.push(code);
      callback();
    }))
    .pipe(fs.createWriteStream('dist/bundle.js'));
}

createBundle();

Transforms

Babel Transform

# Install babelify
npm install --save-dev babelify @babel/core @babel/preset-env

// .babelrc
{
  "presets": ["@babel/preset-env"],
  "plugins": [
    "@babel/plugin-transform-arrow-functions",
    "@babel/plugin-transform-classes"
  ]
}

# Use with browserify
browserify src/js/main.js -t babelify -o dist/bundle.js

CoffeeScript Transform

# Install coffeeify
npm install --save-dev coffeeify coffee-script

# src/js/app.coffee
class Calculator
  constructor: ->
    @result = 0
  
  add: (num) ->
    @result += num
    @
  
  multiply: (num) ->
    @result *= num
    @
  
  getResult: ->
    @result

module.exports = Calculator

# Bundle CoffeeScript
browserify src/js/app.coffee -t coffeeify -o dist/bundle.js

TypeScript Transform

# Install tsify
npm install --save-dev tsify typescript

// src/js/app.ts
interface Calculator {
  add(a: number, b: number): number;
  multiply(a: number, b: number): number;
}

class BasicCalculator implements Calculator {
  add(a: number, b: number): number {
    return a + b;
  }
  
  multiply(a: number, b: number): number {
    return a * b;
  }
}

export default BasicCalculator;

# Bundle TypeScript
browserify src/js/app.ts -p tsify -o dist/bundle.js

CSS Transforms

# Install css transforms
npm install --save-dev browserify-css stringify

// Using browserify-css
const css = require('./styles.css');
document.head.appendChild(css);

# Bundle with CSS
browserify src/js/main.js -t browserify-css -o dist/bundle.js

Environment Variables

# Install envify
npm install --save-dev envify

// src/js/config.js
const config = {
  apiUrl: process.env.API_URL || 'http://localhost:3000',
  debug: process.env.NODE_ENV === 'development',
  version: process.env.npm_package_version
};

module.exports = config;

# Bundle with environment variables
API_URL=https://api.example.com browserify src/js/main.js -t envify -o dist/bundle.js

Plugins

Factor Bundle Plugin

# Install factor-bundle
npm install --save-dev factor-bundle

// Multiple entry points with shared dependencies
const browserify = require('browserify');

const b = browserify({
  entries: ['src/js/page1.js', 'src/js/page2.js']
});

b.plugin('factor-bundle', {
  outputs: ['dist/page1.js', 'dist/page2.js']
});

b.bundle().pipe(fs.createWriteStream('dist/common.js'));

Bundle Collapser

# Install bundle-collapser
npm install --save-dev bundle-collapser

// Reduce bundle size by collapsing modules
const b = browserify('src/js/main.js');
b.plugin('bundle-collapser/plugin');
b.bundle().pipe(fs.createWriteStream('dist/bundle.js'));

Browserify Shim

# Install browserify-shim
npm install --save-dev browserify-shim

// package.json
{
  "browserify": {
    "transform": ["browserify-shim"]
  },
  "browserify-shim": {
    "jquery": "global:jQuery",
    "bootstrap": {
      "depends": ["jquery"],
      "exports": "bootstrap"
    }
  }
}

Disc Plugin (Bundle Analysis)

# Install disc
npm install --save-dev disc

// Analyze bundle size
const browserify = require('browserify');
const disc = require('disc');

const b = browserify('src/js/main.js');
b.plugin(disc, {
  output: 'bundle-analysis.html',
  open: true
});
b.bundle().pipe(process.stdout);

Source Maps

Enabling Source Maps

# Enable debug mode for source maps
browserify src/js/main.js -d -o dist/bundle.js

# Source maps with transforms
browserify src/js/main.js -t babelify -d -o dist/bundle.js

Programmatic Source Maps

const browserify = require('browserify');
const exorcist = require('exorcist');

// External source maps
browserify('src/js/main.js', { debug: true })
  .bundle()
  .pipe(exorcist('dist/bundle.js.map'))
  .pipe(fs.createWriteStream('dist/bundle.js'));

Source Map Options

const b = browserify({
  entries: ['src/js/main.js'],
  debug: true,
  
  // Source map options
  sourceMaps: true,
  sourceMapPrefix: '/src',
  sourceRoot: '/src'
});

Inline Source Maps

// Inline source maps for development
const b = browserify({
  entries: ['src/js/main.js'],
  debug: true
});

// Transform with source maps
b.transform('babelify', {
  sourceMaps: 'inline'
});

External Dependencies

Creating Vendor Bundle

# Create vendor bundle with common libraries
browserify -r jquery -r lodash -r moment -o dist/vendor.js

# Create app bundle excluding vendor libraries
browserify src/js/main.js -x jquery -x lodash -x moment -o dist/app.js

Programmatic External Dependencies

// vendor.js - Create vendor bundle
const browserify = require('browserify');

const vendor = browserify();
vendor.require('jquery');
vendor.require('lodash');
vendor.require('moment');

vendor.bundle().pipe(fs.createWriteStream('dist/vendor.js'));

// app.js - Create app bundle
const app = browserify('src/js/main.js');
app.external('jquery');
app.external('lodash');
app.external('moment');

app.bundle().pipe(fs.createWriteStream('dist/app.js'));

HTML Integration

<!DOCTYPE html>
<html>
<head>
    <title>Multi-bundle App</title>
</head>
<body>
    <!-- Load vendor bundle first -->
    <script src="dist/vendor.js"></script>
    <!-- Then load app bundle -->
    <script src="dist/app.js"></script>
</body>
</html>

Dynamic Externals

// Dynamic external configuration
const externals = ['jquery', 'lodash', 'react', 'react-dom'];

const b = browserify('src/js/main.js');

externals.forEach(lib => {
  b.external(lib);
});

b.bundle().pipe(fs.createWriteStream('dist/app.js'));

Multiple Bundles

Factor Bundle Setup

// build-multiple.js
const browserify = require('browserify');
const factor = require('factor-bundle');

const b = browserify({
  entries: [
    'src/js/pages/home.js',
    'src/js/pages/about.js',
    'src/js/pages/contact.js'
  ]
});

b.plugin(factor, {
  outputs: [
    'dist/home.js',
    'dist/about.js',
    'dist/contact.js'
  ]
});

// Common bundle
b.bundle().pipe(fs.createWriteStream('dist/common.js'));

Page-specific Bundles

// src/js/pages/home.js
const common = require('../common');
const analytics = require('../analytics');

// Home page specific code
const homeController = {
  init() {
    console.log('Home page initialized');
    analytics.track('page_view', 'home');
  },
  
  setupCarousel() {
    // Home page carousel logic
  }
};

homeController.init();
module.exports = homeController;

// src/js/pages/about.js
const common = require('../common');

// About page specific code
const aboutController = {
  init() {
    console.log('About page initialized');
  },
  
  setupTeamGrid() {
    // About page team grid logic
  }
};

aboutController.init();
module.exports = aboutController;

Build Script for Multiple Bundles

// build-all.js
const browserify = require('browserify');
const fs = require('fs');
const path = require('path');

const pages = ['home', 'about', 'contact', 'products'];

// Build individual page bundles
pages.forEach(page => {
  const b = browserify(`src/js/pages/${page}.js`);
  
  // Add common externals
  b.external('jquery');
  b.external('lodash');
  
  b.bundle()
    .pipe(fs.createWriteStream(`dist/${page}.js`))
    .on('finish', () => {
      console.log(`${page}.js bundle created`);
    });
});

// Build vendor bundle
const vendor = browserify();
vendor.require('jquery');
vendor.require('lodash');

vendor.bundle()
  .pipe(fs.createWriteStream('dist/vendor.js'))
  .on('finish', () => {
    console.log('vendor.js bundle created');
  });

Development Workflow

Development Server

# Install budo (development server)
npm install --save-dev budo

// package.json scripts
{
  "scripts": {
    "dev": "budo src/js/main.js:bundle.js --live --open --port 3000",
    "dev:https": "budo src/js/main.js:bundle.js --live --open --ssl",
    "dev:host": "budo src/js/main.js:bundle.js --live --host 0.0.0.0"
  }
}
```### Configurazione Live Reload
```javascript
// dev-server.js
const budo = require('budo');
const babelify = require('babelify');

budo('src/js/main.js:bundle.js', {
  live: true,
  open: true,
  port: 3000,
  stream: process.stdout,
  
  // Browserify options
  browserify: {
    transform: [
      babelify.configure({
        presets: ['@babel/preset-env']
      })
    ],
    debug: true
  }
}).on('connect', (ev) => {
  console.log('Server running on %s', ev.uri);
});
```### Sostituzione Modulo a Caldo (Hot Module Replacement)
```bash
# Install browserify-hmr
npm install --save-dev browserify-hmr

// src/js/main.js with HMR
const app = require('./app');

// Initialize app
app.init();

// Hot module replacement
if (module.hot) {
  module.hot.accept('./app', () => {
    const newApp = require('./app');
    newApp.init();
  });
}
```### Script di Build per Sviluppo
```javascript
// dev-build.js
const browserify = require('browserify');
const watchify = require('watchify');
const babelify = require('babelify');

// Create watchify instance
const b = watchify(browserify({
  entries: ['src/js/main.js'],
  cache: {},
  packageCache: {},
  debug: true
}));

// Add transforms
b.transform(babelify, {
  presets: ['@babel/preset-env']
});

// Bundle function
function bundle() {
  return b.bundle()
    .on('error', (err) => {
      console.error('Bundle error:', err.message);
    })
    .pipe(fs.createWriteStream('dist/bundle.js'))
    .on('finish', () => {
      console.log('Bundle updated');
    });
}

// Watch for changes
b.on('update', bundle);
b.on('log', console.log);

// Initial bundle
bundle();
```## Build di Produzione
```bash
# Install uglifyify
npm install --save-dev uglifyify

# Production build with minification
NODE_ENV=production browserify src/js/main.js -t babelify -g uglifyify -o dist/bundle.min.js
```### Minificazione
```javascript
// build-prod.js
const browserify = require('browserify');
const uglifyify = require('uglifyify');
const envify = require('envify');

// Set production environment
process.env.NODE_ENV = 'production';

const b = browserify({
  entries: ['src/js/main.js'],
  debug: false // Disable source maps for production
});

// Add transforms
b.transform('babelify', {
  presets: ['@babel/preset-env']
});

b.transform('envify', {
  NODE_ENV: 'production'
});

// Global transforms (apply to node_modules)
b.transform('uglifyify', {
  global: true,
  compress: {
    drop_console: true,
    drop_debugger: true
  }
});

// Bundle
b.bundle()
  .pipe(fs.createWriteStream('dist/bundle.min.js'))
  .on('finish', () => {
    console.log('Production bundle created');
  });
```### Script di Build di Produzione
```javascript
// analyze-bundle.js
const browserify = require('browserify');
const disc = require('disc');

const b = browserify('src/js/main.js');

b.plugin(disc, {
  output: 'bundle-analysis.html',
  open: true
});

b.bundle((err, buf) => {
  if (err) {
    console.error('Bundle error:', err);
  } else {
    console.log('Bundle size:', (buf.length / 1024).toFixed(2) + 'KB');
  }
});
```### Analisi Bundle
```javascript
// gzip-analysis.js
const browserify = require('browserify');
const zlib = require('zlib');

browserify('src/js/main.js')
  .bundle((err, buf) => {
    if (err) throw err;
    
    const size = buf.length;
    
    zlib.gzip(buf, (err, gzipped) => {
      if (err) throw err;
      
      const gzipSize = gzipped.length;
      
      console.log('Bundle size:', (size / 1024).toFixed(2) + 'KB');
      console.log('Gzipped size:', (gzipSize / 1024).toFixed(2) + 'KB');
      console.log('Compression ratio:', ((1 - gzipSize / size) * 100).toFixed(1) + '%');
    });
  });
```### Analisi Gzip
```bash
# Install tape
npm install --save-dev tape tap-spec

// test/math.test.js
const test = require('tape');
const math = require('../src/js/math');

test('Math module tests', (t) => {
  t.equal(math.add(2, 3), 5, 'Addition works correctly');
  t.equal(math.multiply(4, 5), 20, 'Multiplication works correctly');
  t.equal(math.subtract(10, 3), 7, 'Subtraction works correctly');
  t.end();
});

// package.json
{
  "scripts": {
    "test": "tape test/*.js | tap-spec"
  }
}
```## Test
```bash
# Install testling
npm install --save-dev testling

// package.json
{
  "testling": {
    "files": "test/*.js",
    "browsers": [
      "ie/9..latest",
      "chrome/latest",
      "firefox/latest",
      "safari/latest"
    ]
  }
}
```### Unit Testing con Tape
```bash
# Install karma and browserify
npm install --save-dev karma karma-browserify karma-chrome-launcher karma-jasmine

// karma.conf.js
module.exports = function(config) {
  config.set({
    frameworks: ['jasmine', 'browserify'],
    
    files: [
      'test/**/*.js'
    ],
    
    preprocessors: {
      'test/**/*.js': ['browserify']
    },
    
    browserify: {
      debug: true,
      transform: ['babelify']
    },
    
    browsers: ['Chrome'],
    
    singleRun: true
  });
};
```### Test Browser
```javascript
// test/api.test.js
const test = require('tape');
const proxyquire = require('proxyquire');

// Mock HTTP requests
const apiModule = proxyquire('../src/js/api', {
  'http': {
    get: (url, callback) => {
      // Mock response
      callback({
        statusCode: 200,
        body: JSON.stringify({ success: true })
      });
    }
  }
});

test('API module tests', (t) => {
  apiModule.fetchData((err, data) => {
    t.error(err, 'No error occurred');
    t.ok(data.success, 'API returned success');
    t.end();
  });
});
```### Integrazione Karma
```javascript
// transforms/custom-transform.js
const through = require('through2');
const path = require('path');

module.exports = function(file, opts) {
  // Only process .custom files
  if (path.extname(file) !== '.custom') {
    return through();
  }
  
  let content = '';
  
  return through(
    function(chunk, enc, callback) {
      content += chunk.toString();
      callback();
    },
    function(callback) {
      // Transform the content
      const transformed = content
        .replace(/CUSTOM_SYNTAX/g, 'JavaScript equivalent')
        .replace(/\$\{([^}]+)\}/g, '" + $1 + "');
      
      this.push('module.exports = ' + JSON.stringify(transformed));
      callback();
    }
  );
};
```### Mocking e Stubbing
```javascript
// plugins/custom-plugin.js
module.exports = function(b, opts) {
  opts = opts || {};
  
  b.on('bundle', function(bundle) {
    console.log('Bundle started');
  });
  
  b.pipeline.get('record').push(through.obj(function(row, enc, next) {
    // Modify module records
    if (row.file.endsWith('.special.js')) {
      row.source = '// Special processing\n' + row.source;
    }
    this.push(row);
    next();
  }));
};
```## Funzionalità Avanzate
```javascript
// conditional-build.js
const browserify = require('browserify');

const isProduction = process.env.NODE_ENV === 'production';
const isDevelopment = !isProduction;

const b = browserify({
  entries: ['src/js/main.js'],
  debug: isDevelopment
});

// Conditional transforms
if (isDevelopment) {
  b.transform('browserify-hmr');
} else {
  b.transform('uglifyify', { global: true });
}

// Conditional plugins
if (isProduction) {
  b.plugin('bundle-collapser/plugin');
}

b.bundle().pipe(fs.createWriteStream(
  isProduction ? 'dist/bundle.min.js' : 'dist/bundle.js'
));
```### Transform Personalizzati
```javascript
// src/js/dynamic-loader.js
const loadModule = (moduleName) => {
  return new Promise((resolve, reject) => {
    // Dynamic require (note: this needs special handling in browserify)
    try {
      const module = require(`./modules/${moduleName}`);
      resolve(module);
    } catch (err) {
      reject(err);
    }
  });
};

// Usage
loadModule('feature-a').then(module => {
  module.init();
});
```### Sviluppo Plugin
```javascript
// Split bundles by feature
const features = ['auth', 'dashboard', 'settings'];

features.forEach(feature => {
  const b = browserify(`src/js/features/${feature}/index.js`);
  
  // External common dependencies
  b.external('jquery');
  b.external('lodash');
  
  b.bundle()
    .pipe(fs.createWriteStream(`dist/${feature}.js`));
});
```### Bundling Condizionale
```javascript
// src/js/lazy-loader.js
const lazyLoad = (modulePath) => {
  return new Promise((resolve) => {
    // Simulate dynamic loading
    setTimeout(() => {
      const module = require(modulePath);
      resolve(module);
    }, 100);
  });
};

// Usage in main app
document.getElementById('load-feature').addEventListener('click', () => {
  lazyLoad('./features/advanced-feature').then(feature => {
    feature.initialize();
  });
});
```### Import Dinamici
```javascript
// advanced-splitting.js
const browserify = require('browserify');
const factor = require('factor-bundle');

// Define entry points
const entries = [
  'src/js/pages/home.js',
  'src/js/pages/products.js',
  'src/js/pages/checkout.js'
];

const b = browserify({
  entries: entries,
  debug: false
});

// Configure factor bundle
b.plugin(factor, {
  outputs: [
    'dist/home.js',
    'dist/products.js',
    'dist/checkout.js'
  ],
  threshold: 1 // Minimum number of bundles a module must be in to be factored out
});

// Common bundle
b.bundle()
  .pipe(fs.createWriteStream('dist/common.js'))
  .on('finish', () => {
    console.log('Code splitting completed');
  });
```## Ottimizzazione delle Prestazioni
```javascript
// optimize-bundle.js
const browserify = require('browserify');
const uglifyify = require('uglifyify');
const bundleCollapser = require('bundle-collapser/plugin');

const b = browserify('src/js/main.js');

// Optimization transforms and plugins
b.transform('uglifyify', {
  global: true,
  compress: {
    drop_console: true,
    drop_debugger: true,
    pure_funcs: ['console.log', 'console.info']
  },
  mangle: {
    reserved: ['$', 'jQuery']
  }
});

b.plugin(bundleCollapser);

// Ignore unnecessary modules
b.ignore('fs');
b.ignore('path');
b.ignore('crypto');

b.bundle()
  .pipe(fs.createWriteStream('dist/bundle.optimized.js'));
```### Suddivisione Bundle
```bash
# Enable debug mode for detailed output
browserify src/js/main.js -d -o dist/bundle.js

# Verbose output
browserify src/js/main.js -v -o dist/bundle.js
```### Debug Mappe Sorgente
```javascript
// Enable source maps in development
const b = browserify({
  entries: ['src/js/main.js'],
  debug: true, // Enables inline source maps
  fullPaths: true // Keep full paths for better debugging
});
```### Analisi Bundle
```javascript
// debug-bundle.js
const browserify = require('browserify');
const deps = require('browserify-deps');

// Analyze dependencies
browserify('src/js/main.js')
  .pipeline.get('deps')
  .pipe(deps())
  .pipe(through.obj(function(row, enc, next) {
    console.log('Module:', row.file);
    console.log('Dependencies:', row.deps);
    console.log('---');
    next();
  }));
```### Gestione degli Errori
```javascript
// error-handling.js
const browserify = require('browserify');

const b = browserify('src/js/main.js');

b.bundle()
  .on('error', function(err) {
    console.error('Browserify error:');
    console.error('Message:', err.message);
    console.error('File:', err.filename);
    console.error('Line:', err.line);
    console.error('Column:', err.column);
    
    // Don't exit process in watch mode
    this.emit('end');
  })
  .pipe(fs.createWriteStream('dist/bundle.js'));
```### Profilazione
```javascript
// profile-build.js
const browserify = require('browserify');

console.time('Bundle time');

browserify('src/js/main.js')
  .bundle()
  .pipe(fs.createWriteStream('dist/bundle.js'))
  .on('finish', () => {
    console.timeEnd('Bundle time');
    
    // Memory usage
    const used = process.memoryUsage();
    console.log('Memory usage:');
    for (let key in used) {
      console.log(`${key}: ${Math.round(used[key] / 1024 / 1024 * 100) / 100} MB`);
    }
  });
```## Migrazione
```javascript
// webpack.config.js equivalent in Browserify
// Webpack:
// module.exports = {
//   entry: './src/index.js',
//   output: {
//     filename: 'bundle.js',
//     path: path.resolve(__dirname, 'dist')
//   },
//   module: {
//     rules: [{
//       test: /\.js$/,
//       use: 'babel-loader'
//     }]
//   }
// };

// Browserify equivalent:
const browserify = require('browserify');

browserify('./src/index.js')
  .transform('babelify')
  .bundle()
  .pipe(fs.createWriteStream('dist/bundle.js'));
```### Da Webpack
```javascript
// RequireJS config equivalent
// requirejs.config({
//   baseUrl: 'src/js',
//   paths: {
//     'jquery': 'vendor/jquery',
//     'lodash': 'vendor/lodash'
//   }
// });

// Browserify approach - use npm modules
// npm install jquery lodash

// src/js/main.js
const $ = require('jquery');
const _ = require('lodash');

// Use modules normally
$('#app').text('Hello from Browserify');
```### Da RequireJS
```javascript
// Good: Clear module structure
// src/js/modules/user.js
const api = require('../api');
const utils = require('../utils');

class User {
  constructor(data) {
    this.data = data;
  }
  
  save() {
    return api.post('/users', this.data);
  }
  
  format() {
    return utils.formatUser(this.data);
  }
}

module.exports = User;
```### Migrazione Checklist
- [ ] Convertire moduli AMD/RequireJS in CommonJS
- [ ] Installare equivalenti npm delle librerie vendor
- [ ] Aggiornare script di build per usare Browserify
- [ ] Configurare trasformazioni per preprocessing
- [ ] Impostare workflow di sviluppo con watchify
- [ ] Aggiornare HTML per usare script bundled
- [ ] Testare tutta la funzionalità dopo la migrazione
```json
// package.json - Clear separation of dependencies
{
  "dependencies": {
    "jquery": "^3.6.0",
    "lodash": "^4.17.21"
  },
  "devDependencies": {
    "browserify": "^17.0.0",
    "babelify": "^10.0.0",
    "watchify": "^4.0.0"
  }
}
```## Migliori Pratiche
```javascript
// build-config.js - Centralized configuration
const config = {
  entry: 'src/js/main.js',
  output: 'dist/bundle.js',
  
  transforms: [
    ['babelify', { presets: ['@babel/preset-env'] }]
  ],
  
  plugins: process.env.NODE_ENV === 'production' ? [
    'bundle-collapser/plugin'
  ] : [],
  
  external: ['jquery', 'lodash'],
  
  debug: process.env.NODE_ENV !== 'production'
};

module.exports = config;
```### Organizzazione Moduli