contabilidad/api/setup/settings/03_database.php

<?php
return [
  'databases' => function() {
    $arr = [
      'default' => [
        'type' => 'mysql',
        'host' => [
          'name' => $_ENV['MYSQL_HOST'] ?? 'db'
        ],
        'user' => [
          'name' => $_ENV['MYSQL_USER'],
          'password' => $_ENV['MYSQL_PASSWORD']
        ],
        'name' => $_ENV['MYSQL_DATABASE']
      ]
    ];
    return (object) ['databases' => \ProVM\Implement\Collection::fromArray($arr), 'short_names' => true];
  }
];