All container based on phpx.x-alpine3.x.
$ docker run --rm --interactive --tty \
--volume $PWD:/app \
ccdirk/composer:<tag> <command>
$ eval $(ssh-agent); \
docker run --rm --interactive --tty \
--volume $PWD:/app \
--volume $SSH_AUTH_SOCK:/ssh-auth.sock \\
--env SSH_AUTH_SOCK=/ssh-auth.sock \
--volume ~/.ssh:/root/.ssh \
ccdirk/composer:<tag>