Create a new Composer-managed CMS site
Learn how to create new integrated composer Drupal and WordPress sites on Pantheon.
Drupal with Integrated Composer
This section provides information on how to use Drupal with Integrated Composer.
Create Your Site
There are two ways you can spin up a site using Drupal Composer Managed:
Running the following terminus command:
terminus site:create --org ORG --region REGION -- <site_name> <label> drupal-11-composer-managedUsing this site create link.
The site you create will be based on the Pantheon-maintained Drupal Composer Managed upstream. Once this install completes, visit the Dev environment and follow the prompts to complete the CMS installation.
Understand the Drupal Codebase
Composer installs required packages into configured paths for Drupal, such as:
- Contributed themes are installed into 
web/themes/contrib/ - Custom themes are installed into 
web/themes/custom/ - Contributed modules are installed into 
web/modules/contrib/ - Custom modules are installed into 
web/modules/custom/ - Drupal core is installed into 
web/core/ - Librariries are installed into 
web/libraries/ 
For more information about managing dependencies with Composer on Pantheon, see our documentation about dependencies or the Composer documentation.
WordPress with Integrated Composer and Bedrock
This section provides information on how to use Bedrock with Integrated Composer on a WordPress site.
WordPress does not natively support Composer, however, Bedrock is a WordPress-specific framework for using Composer on WordPress sites.
Requirements
- PHP version 8.0 or greater
 - Composer
 
Create Your Site
There are two ways you can spin up a site using WordPress Composer Managed:
Running the following terminus command:
terminus site:create --org ORG --region REGION -- <site_name> <label> wordpress-composer-managedUsing this site create link.
The site you create will be based on the Pantheon-maintained WordPress Composer Managed upstream. Once this install completes, visit the Dev environment and follow the prompts to complete the CMS installation.
Review the sections below for important information about your site, including an explanation of the directory structure and essential configuration actions.
Use Roots Bedrock
Environment Variables
Bedrock makes use of an .env file to store environment variables. Pantheon takes care of many of these variables in .env.pantheon. You may set your own environment variables in a new .env or environment variables that are local-only in .env.local using the .env.example as a guide. Wrap values that may contain non-alphanumeric characters with quotes, or they may be incorrectly parsed.
WordPress Config
The wp-config.php file is located in the web directory. As with other WordPress sites on Pantheon, much of this is taken care of for you in wp-config-pantheon.php. Application-level configuration takes place in config/application.php while platform-specific updates are made in config/application.pantheon.php. This means that config/application.php can be modified for your WordPress configuration settings without fear of conflicts with the upstream. Any configuration changes should be made to your config/appliction.php not your wp-config.php file directly.
You can learn more about WordPress configuration with Bedrock in the Bedrock Configuration docs.
Understand the WordPress Codebase
Bedrock installs WordPress as a required package so updates can be managed by Composer. As such, the contents of the wp-content directory have been moved outside the WordPress codebase so changes can be made safely to files within those directories without conflicts. Learn more about Bedrock's folder structure here.
- Themes are installed into 
web/app/themes/ - Plugins are installed into 
web/app/plugins - Must-use plugins are installed into 
web/app/mu-plugins - WordPress core is installed into 
web/wp - The WordPress admin dashboard is available at 
https://example.com/wp/wp-admin/ 
For more information about managing dependencies with Composer on Pantheon, see our documentation about dependencies or the Composer documentation.