Add this project to any Drupal distribution based on drupal/core-composer-scaffold to enable it for use on Pantheon.

This project enables the following Pantheon/Drupal integrations:

• Injects the Pantheon database credentials for the Drupal site
• Provides a default PHP version to use (7.3)
• Enables HTTPS (in transitional mode) by default
• Demonstrates how to turn on twig debugging on non-production Pantheon environments
• Sets the path to:
  • Configuration import / export directory
  • Private files
  • Temporary files
  • Twig cache files
• Establishes a secure, random hash salt for Drupal
• Injects the Pantheon Service Provider (clears edge cache on cache rebuild, etc.)
• Prevents the user from updating Drupal core with Drush
• Configures the trusted host patterns to avoid a warning that is not applicable to Panthoen
• Ignores large cache directories (e.g. node modules and bower components)

This project must be enabled in the top-level composer.json file, or it will be ignored and will not perform any of its functions.

{
    ...
    "require": {
        "pantheon-systems/drupal-integrations": "^9"
    },
    ...
    "extra": {
        "drupal-scaffold": {
            "allowed-packages": [
                "pantheon-systems/drupal-integrations"
            ]
        }
    }
}

Use version "^8" for Drupal 8, and version "^9" for Drupal 9.