Drupal 7 - Wercker configuration

wercker.yml

box: wercker/php
services:
    - wercker/mysql
build:
    steps:
    -  script:
          name: Install Drush
          code: |-
              pear channel-discover pear.drush.org
              pear install drush/drush
              phpenv rehash
    -  script:
          name: Install Drupal
          code: |-
              drush site-install standard --db-url=$WERCKER_MYSQL_URL --site-name=Testing -y
    -  script:
          name: Enable simpletest
          code: |-
              drush en simpletest -y
              drush vset --yes simpletest_verbose FALSE
    -  script:
          name: Start server
          code: |-
              drush runserver --server=builtin 8080 & sleep 5
    -  script:
          name: Run tests
          code: |-
              drush test-run DrupalGotoTest --xml --uri=http://127.0.0.1:8080