@Test
public void instantiating () throws Exception {

  val name = createName();
  node = Nodes.singleNode(name, NodeConfig.builder()
                          .shortName(true)
                          .mailbox(MailboxConfig.builder()
                              .name("one")
                              .build())
                          .mailbox(MailboxConfig.builder()
                              .name("two")
                              .build())
                          .build()
  );
  assertThat(node.mailbox("one")).isNotNull();
  assertThat(node.mailbox("two")).isNotNull();
  assertThat(node.mailbox("three")).isNull();
}