The composer.json file


Magento 2 uses Composer, a PHP dependency manager, to package components and product editions.

Composer reads a composer.json file in Magento’s root directory to download third-party dependencies listed in the file.

The Component Manager uses the composer.json file in an extension’s root directory to perform the following actions:

  • The Component Manager can update, uninstall, enable, or disable an extension if installed using Composer (including from Packagist, Magento Marketplace, or other source) and it has a composer.json file.
  • The Component Manager can still enable or disable an extension not installed using Composer (e.g. custom code) if it has a composer.json file.

We recommend you include composer.json in your component’s root directory even if you do not intend to distribute it to other merchants using Magento.

Magento does not support the path repository.

Composer binary location

Magento uses the composer binary in the <Magento root>/vendor/composer directory instead of a globally installed composer.

Keep this in mind while customizing, updating, or troubleshooting composer while working with Magento 2.

Project vs product

In Composer, a “project” package is a template used by the composer create-project to set up the project structure. The installation instructions for system integrators use the Magento Open Source and Magento Commerce project packages to set up the Magento directory structure.

A “product” package is the actual application pointed to by the composer.json file after you download and install the project package using composer create-project.

Descriptions of different composer.json files

The following Magento components and product editions use a composer.json file.

Magento Root

Location: composer.json

Name: magento/magento2ce

Type: project

This is Magento’s main composer.json file which declares dependencies and third-party components.

Other root composer.json files use this file as a template.

Magento Open Source project

Location: composer.json

Name: magento/project-community-edition

Type: project

Magento system integrators use this composer.json file to deploy the Magento Open Source product and its dependencies.

Magento Commerce project

Location: composer.json

Name: magento/product-enterprise-edition

Type: metapackage

Magento system integrators use this composer.json file to deploy the Magento Commerce product and its dependencies.

Magento Framework

Location: lib/internal/Magento/Framework/composer.json

Name: magento/framework

Type: magento2-library

The Magento application uses this composer.json file for its framework packages.



  • app/code/<vendor-name>/<module-name>/composer.json
  • vendor/<vendor-name>/<module-name>/composer.json

Name: <vendor-name>/<package-name>

Type: magento2-module

The composer.json file for a module extension declares external dependencies that it needs to function.



  • app/design/frontend/<vendor-name>/<theme-name>/composer.json
  • app/design/adminhtml/<vendor-name>/<theme-name>/composer.json

Name: <vendor-name>/<package-name>

Type: magento2-theme

The composer.json file for a theme component contains parent theme dependencies the extension needs to inherit.

Language Package

Location: app/i18n/<vendor-name>/<language-code>/composer.json

Name: <vendor-name>/<package-name>

Type: magento2-language

For language packages, you must use the correct ISO code for the language code in the composer.json file.

Magento-specific package types

Magento extensions can be any of the following types:

  • magento2-module for modules
  • magento2-theme for themes
  • magento2-language for language packages
  • magento2-component for general extensions that do not fit any of the other types

The extension type tells the system where to install the directories and files of each extension in the Magento directory structure.

Naming conventions

Since the namespace of a Composer package is global within a package repository, e.g., use the following format when naming your package:


Using the Composer naming convention helps distinguish packages from different vendors with a low risk of overlapping.


All letters in the vendor name must be in lowercase. For example, the vendor name format for extensions released by Magento Inc is magento.

Magento Marketplace Extensions

Magento Marketplace uses vendor-name to match an extension to a vendor during the extension submission process. If you plan to submit your extension to the Magento Marketplace, you must use the unique Vendor Name created or assigned to you when you created your marketplace account.

In the composer.json file, use the value of ‘Vendor Name’ in your profile for the vendor-name part of the extension name.

Please see the Marketplace Documentation for more information about your unique vendor name.


All letters in the package-name must be in lowercase.

If the name contains more than one word, the Composer specification recommends separating them with dashes.

The convention for Magento package names is the following



:type-prefix is any of the Magento extension types:

  • module- for module extensions
  • theme- for theme extensions
  • language- for language extensions
  • product- for metapackages such as Magento Open Source or Magento Commerce

: suffix is a unique identifier for extensions of that type.


Components have the following types of versions:

  • Marketing version; in other words, the version the merchant interacts with.

    Your initial version might be 1.0.0 or 2.0.0, for example. You should follow our versioning policy guidelines when setting your version.

  • Composer version; in other words, the version of each module, theme, language package, third-party package, and dependencies.

Using Magento code as an example, Magento Open Source marketing version 2.0.0 includes component versions such as 100.0.1, 100.0.2, and so on. These versioning strategy prevents collisions between the marketing version and component versions.

Next: Define your configuration files