drushrc.php

<?php
// Load a drushrc.php file from the 'drush' folder at the root
// of the current git repository.
exec('git rev-parse --git-dir 2> /dev/null', $output);
if (!empty($output)) {
  $repo = $output[0];
  $options['config'] = $repo . '/../drush/drushrc.php';
  $options['include'] = $repo . '/../drush/commands';
  $options['alias-path'] = $repo . '/../drush/aliases';
}
$options['variables']['language_default']->language = 'en';