It is about time for front-end developers to have a decent package manager. Front-end development is serious business and there is no good reason for us to continue with sub-par tools or no tools at all.

I appreciate the effort that has gone into all of these. It is awesome to see really talented developers taking on the task and sharing the result with the rest of us.

• I am a full-stack software developer
• I love what I do
• I love sharing what I've learned
• Hit me up at @wilmoore, @github, and @linkedin

The following tools have caught my attention:

• bower
• component
• jam
• volo
• npm with browserify
• spm

NOTES:

• component is more of a concept and a framework for building and distributing front-end components. If you'd like to read more on this distinction, check out the issue #1 thread.
• bower is meant to be consumed by higher-level tools and frameworks. What this means in practice is:
• (1) bring your own CJS/AMD loader.
• (2) bring your own build tool.
• (3) bring your own organization conventions.
• (4) ultimately, coupled with either make or grunt, bower looks like a viable option

A package manager is a tool that allows you to specify a list of dependencies for your library or application. The tools depicted here are similar in scope to Bundler, NPM, or Composer.

Since tool choice is extremely subjective, you (and/or your team) should come up with your own weighting system and score each tool accordingly.

The following table provides the name of the "manifest" file where you specify dependencies and/or the details of your package.

Sample bower enabled bower.json file:

{
  "name": "my-project",
  "version": "1.0.0",
  "main": "path/to/main.css",
  "ignore": [
    ".jshintrc",
    "**/*.txt"
  ],
  "dependencies": {
    "<name>": "<version>",
    "<name>": "<folder>",
    "<name>": "<package>"
  },
  "devDependencies": {
    "<test-framework-name>": "<version>"
  }
}

Sample component enabled component.json file:

{

  "name":        "tip",
  "repo":        "component/tip",
  "description": "Tip component",
  "version":     "0.0.1",
  "keywords":    ["tooltip", "tip", "ui"],
  "dependencies": {
    "component/emitter": "*",
    "component/jquery":  "*"
  },
  "scripts": ["index.js", "template.js"],
  "styles":  ["tip.css"]

}

Sample jam enabled package.json file:

{

  "name":        "csbp",
  "version":     "0.0.1",
  "description": "A Non-Framework Client-Side JavaScript/HTML5 Project Boilerplate",

  "dependencies": {
    "jamjs":         "*",
    "grunt-contrib": "*"
  },

  "devDependencies": {
    "chai":          "*",
    "mocha":         "*",
    "sinon":         "*",
    "grunt-mocha":   "*"
  },

  "jam": {
    "packageDir": "src/libs/js",
    "baseUrl":    "src/main/js"
  }

}

Sample volo enabled package.json file:

 {

  "name":            "csbp",
  "version":         "0.0.1",
  "description":     "A Non-Framework Client-Side JavaScript/HTML5 Project Boilerplate",

  "dependencies": {
  },

  "devDependencies": {
    "yeti":          "*",
    "docco":         "*",
    "jshint":        "*",
    "chai":          "*",
    "mocha":         "*",
    "sinon":         "*"
  },

  "amd":  {},

  "volo": {
    "baseUrl":       "src/js/lib",

    "dependencies":  {
      "page":        "github:visionmedia/page.js",
      "requirejs":   "*"
    }
  }

}

Sample npm + browserify enabled package.json file:

{
  "name": "{{project}}",
  "version": "1.0.0",
  "description": "{{description}}",

  "repository": "git://github.com/{{author}}/{{project}}.git",
  "main": "index.js",

  "dependencies": {
    "hyperquest": "~0.1.0"
  },
  "devDependencies": {
    "mocha": "*"
  },

  "licenses": "MIT"
}

Sample spm enabled package.json file:

{
  "name": "{{project}}",
  "version": "1.0.0",
  "description": "{{description}}",

  "repository": "git://github.com/{{author}}/{{project}}.git",

  "spm": {
    "main": "index.js",
    "dependencies": {
      "moment": "2.8.1",
      "jquery": "1.11.1"
    }
  },

  "licenses": "MIT"
}

NOTES:

• There is an interesting discussion regarding some of the reasoning behind bower not supporting the well-known package.json format.
• When using volo, I would suggest using the flags:
  • -nostamp: mitigates the reformating of your package.json file
  • skipexists: skip existing dependencies without noisy warnings
• When using npm with browserify you can optionally add a "browser" field to package.json which overrides the "main" field. See the browser spec for more info.

The following table details where each tool stores downloaded packages.

NOTES:

volo has a fairly complex algorithm.

If not defined in package.json it:

• Looks for a ./js directory
• Looks for a ./scripts directory
• Otherwise, the current working directory is used

The following table details whether each tool allows specifying development dependencies.

NOTES:

• Since jam, volo and npm use package.json, this just works; however, component re-implements this functionality here.

The following table details the responsibilities the given tool takes on.

NOTES:

• Project bootstrapping (i.e. component create mycomponent) is generally very minimal.
• Project scaffolding (i.e. volo create username/template-repo) can be a bit more involved.
• An interesting comparison of volo and grunt.

The following table details which tools require a build/compile step during development.

NOTES:

• N/A

The following table details which tools expose a central "registry".

NOTES:

• It is good etiquette to use user/package namespacing when registering a package (except in npm)

The following table details the method by which each tool allows you to specify each dependency (i.e. dependencies).

NOTES:

• I've never been on a serious team where no support for private repositories would be acceptable. If this is important to you, it seems that your best options are currently bower, component, jam and npm.
• While volo doesn't actually claim to have explicit support for private repositories, you can achieve the notion of private repositories by providing a URL to a single JavaScript source file (github and github:enterprise allow you to link to a raw file) or you can specify a URL to a zipball. There are a few more tricks that you can choose from listed here.
• You can setup a private jam free repo from garden20. Other details for a private repo can be found here.
• Jam allows this jam install gh:visionmedia/page.js but only via the command-line (no package.json support).

The following table details the speed of each tool.

NOTES:

• For most projects, speed won't be an issue; however, YMMV.
• These benchmarks were taken from the component documentation; thus depending on your setup and dependencies, YMMV.

The following table details the JavaScript format each tool expects/handles.

NOTES:

There are several JavaScript formatting methodologies:

• Global Script

    <script src="todo.js"></script>
    <script>
       var todo = new Todo({description: '', done: false});
    </script>
  

• AMD

    define(['todo'], function(Todo){
       var todo = new Todo({description: '', done: false});
    });
  

• CommonJS/NodeJS

    var Todo = require('todo');
    var todo = new Todo({description: '', done: false});
  

• CommonJS (wrapped in an AMD-style define)

    define(function(require){
       var Todo = require('todo');
       var todo = new Todo({description: '', done: false});
    });
  

NOTES:

• browserify supports transformations, which would make it simple to support other module formats

The following table details the module/script loader supported by each tool.

NOTES:

Loaders that you might be interested in:

• Browserify
• inject
• curl
• requirejs
• cajon
• almond
• Shepherd-js
• Sea.js

The following table details the the types of source files that can be contained in each package per tool.

NOTES:

• npm lets you install any arbitrary files (much like bower) so you could bring your own loader for CSS and HTML.
• browserify can facilitate loading static assets via brfs which analyzes the AST for fs.readFileSync() calls and inlines file contents. See comment by @substack for more details.

Each package manager is built by talented, responsive, and friendly developers. Ultimately, to evaluate for your team, you will have to put a weight on each category and score per your needs.

Library and component authors may want to consider:

• Using a UMD wrapper.
• Authoring both a {component,package}.json for front-end and npm (where appropriate).
• Adhering to these Library best practices or something similar.

Below is a list of resources that will likely be useful to you if you found this comparison useful:

• JavaScript Modules: A Beginner’s Guide
• Package Managers: An Introductory Guide For The Uninitiated Front-End Developer
• Browser field spec for package.json
• Landscaping With Front-end Tools
• A novel, efficient approach to JavaScript loading
• Confused About Components
• Web Platform Tools
• JavaScript: Noteworthy Tools & Libraries
• The State of Javascript Package Management
• Javascript loaders

I am sure I've made a few grammatical and spelling errors. I've probably even made comparison errors in a few spots. Please feel free to speak up or submit a pull request.