parallelising RSpec test with docker

docker-compose.yml

version: '2'

services: 
    feature_tests:
        image: project/image:ci
        container_name: features_tests
        command: bash -c "service postgresql start; sleep 1m; xvfb-run -a rspec spec/features"
    controller_tests:
        image: project/image:ci
        container_name: controller_tests
        command: bash -c "service postgresql start; sleep 1m; rspec spec/controllers"
    helper_tests:
        image: project/image:ci
        container_name: helper_tests
        command: bash -c "service postgresql start; sleep 1m; rspec spec/helpers"
    interactor_tests:
        image: project/image:ci
        container_name: interactor_tests
        command: bash -c "service postgresql start; sleep 1m; rspec spec/interactors"
    lib_tests:
        image: project/image:ci
        container_name: lib_tests
        command: bash -c "service postgresql start; sleep 1m; rspec spec/lib"
    mailer_tests:
        image: project/image:ci
        container_name: mailer_tests
        command: bash -c "service postgresql start; sleep 1m; rspec spec/mailers"
    model_tests:
        image: project/image:ci
        container_name: model_tests
        command: bash -c "service postgresql start; sleep 1m; rspec spec/models"
    presenter_tests:
        image: project/image:ci
        container_name: presenter_tests
        command: bash -c "service postgresql start; sleep 1m; rspec spec/presenters"
    services_tests:
        image: project/image:ci
        container_name: services_tests
        command: bash -c "service postgresql start; sleep 1m; rspec spec/services"
    view_tests:
        image: project/image:ci
        container_name: view_tests
        command: bash -c "service postgresql start; sleep 1m; rspec spec/views"
    worker_tests: 
        image: project/image:ci
        container_name: worker_tests
        command: bash -c "service postgresql start; sleep 1m; rspec spec/workers"