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Learn more about using WordPress with Composer on Pantheon.

Composer is a widely-used PHP dependency and package manager that provides a simplified method to manage the external (non-core) code used by a WordPress site.

At the most basic level, Composer requires:

  • A list of dependencies
  • A place to put the dependencies

There are different cases for using Composer to manage dependencies on a WordPress site, including:

  • Manage dependencies for themes and plugins you’re currently developing

  • Manage the themes and plugins currently used on the site

  • Total site dependency management, including custom code

First Steps

Complete the steps below before using this guide to create or manage updates on your Pantheon Composer-managed WordPress site.

Existing WordPress Composer Sites

Please reach out to our Professional Services team for information on site migration services if you have an existing Composer-managed WordPress site that you would like to migrate to the Pantheon platform.

  1. Review Composer's documentation to understand how Composer can be used independently of WordPress.

  2. Review Composer Fundamentals Dependencies.

  3. Review Managing Core as Project Dependency.

  4. Review Custom Upstream Workflow.

More Resources