./pants --changed-since=HEAD~1 --changed-dependees=transitive publish \
          --docker-build-args="[ \
            'DD_ENV=${STAGE}', \
            'DD_VERSION=${COMMIT_REF}', \
            'STAGE=${STAGE}', \
            'ECR_REGISTRY=${ECR_REGISTRY}', \
            'IMAGE_TAG=${COMMIT_REF}', \
            'A_REPOSITORY=${A_REPOSITORY}', \
            'B_REPOSITORY=${B_REPOSITORY}', \
            'C_REPOSITORY=${C_REPOSITORY}', \
          ]"

I am using this command to deploy docker to ecs(actually ecr) 1. I want to deploy when something changed in the container. Is that the right way I am doing now? Is there better way? 2. I want to add more repository here but I am worried that cd speed is a bit slower. What is the best way to deploy multiple docker image? 3. Is there any way to check updated image, so that I can use the output for the next step? (to ecs run)