String sharedDatabaseUrl = System.getenv("SHARED_DATABASE_URL");
    Matcher m = Pattern.compile("postgres://(.+):(.+)@(.+)/(.+)").matcher(sharedDatabaseUrl);
    if (m.matches()) {
      String postgresUser = m.group(1);
      String postgresPassword = m.group(2);
      String postgresHost = m.group(3);
      String postgresName = m.group(4);
      String jdbcUrl = String.format("jdbc:postgresql://%s/%s", postgresHost, postgresName);

      properties.setProperty(EntityManagerProperties.JDBC_USER, postgresUser);
      properties.setProperty(EntityManagerProperties.JDBC_PASSWORD, postgresPassword);
      properties.setProperty(EntityManagerProperties.JDBC_URL, jdbcUrl);
      EntityManagerFactory emf = Persistence.createEntityManagerFactory(persistenceUnitName, properties);