I have an application with Composer dependencies which I want to deploy to an Elastic Beanstalk container. However my composer.json file is not in the project root folder.
Composer is already installed default in Beanstalk's PHP AMI.
Also consider that container_commands are ran through '/var/app/ondeck' and not on current. Try something like this:
container_commands: 01-install-packages: command: "composer.phar install -d /var/app/ondeck/www"