Composer’s official stance is you must not commit dependencies.

On occasion, extenuating circumstances require you to commit your dependencies. For BLT, you can commit your dependencies by using the following steps:

1. Change your project’s .gitignore by removing the following lines:

   docroot/core
   docroot/modules/contrib
   docroot/themes/contrib
   docroot/profiles/contrib
   docroot/libraries
   drush/contrib
   vendor
   

2. Create a custom deploy.exclude_file and reference its location in your blt.yml file:

   mkdir blt/deploy && cp vendor/acquia/blt/scripts/blt/deploy/deploy-exclude.txt blt/deploy/deploy-exclude.txt
   
   deploy:
     exclude_file: ${repo.root}/blt/deploy/deploy_exclude.txt
   

3. Change your custom deploy_exclude.txt file by removing the following lines:

   /docroot/core
   /docroot/libraries/contrib
   /docroot/modules/contrib
   /docroot/sites/*/files
   /docroot/sites/*/private
   /docroot/themes/contrib
   /drush/contrib
   /vendor
   

4. Configure deploy.build-dependencies to false in your blt/blt.yml file:

   deploy:
     build-dependencies: false
   

5. Commit your changes and dependencies:

   git add -A
   git commit -m 'Committing dependencies.'
   

Your dependencies will now be committed to your repository and copied to your deployment artifact.