}

    taskFaker.runTasks()
    assertEvents(
      "take plan 0",
      "plan 0 TCP connecting...",
    )

    taskFaker.advanceUntil(250.ms)
    assertEvents(
      "take plan 1",
      "plan 1 TCP connecting...",
    )

    taskFaker.advanceUntil(500.ms)
    assertEvents(
      "take plan 2",
      "plan 0 cancel",
      "plan 1 cancel",
    )

      return@schedule -1L
    }

    queue.idleLatch().await(500, TimeUnit.MILLISECONDS)

    assertThat(log.take()).isEqualTo("failing task running")
    assertThat(log.take()).isEqualTo("uncaught exception: java.lang.RuntimeException: boom!")
    assertThat(log.take()).isEqualTo("normal task running")
    assertThat(log).isEmpty()
  }

  @Test fun idleLatchAfterShutdown() {
    queue.schedule("task") {

    }
  }

  /** Manages a {@link BlockingQueue} and associated timings for a {@code take} call. */
  private static final class TimedTakeQueue {
    final BlockingQueue<String> queue;
    final Completion completed;

    /**
     * Creates a {@link EnableReads} which insert an element for a {@code take} to receive in {@code
     * countdownInMillis}.
     */

    }
  }

  /** Manages a {@link BlockingQueue} and associated timings for a {@code take} call. */
  private static final class TimedTakeQueue {
    final BlockingQueue<String> queue;
    final Completion completed;

    /**
     * Creates a {@link EnableReads} which insert an element for a {@code take} to receive in {@code
     * countdownInMillis}.
     */

      // Fail fast if there's no response queued up.
      return failFastResponse!!
    }

    val result = responseQueue.take()

    // If take() returned because we're shutting down, then enqueue another dead letter so that any
    // other threads waiting on take() will also return.
    if (result == DEAD_LETTER) responseQueue.add(DEAD_LETTER)

    return result
  }

  override fun peek(): MockResponse {

Instead of that, by being an "asynchronous" system, once finished, the task can wait in line a little bit (some microseconds) for the computer / program to finish whatever it went to do, and then come back to take the results and continue working with them.

    fun connectTcp(): ConnectResult

    fun connectTlsEtc(): ConnectResult

    fun handleSuccess(): RealConnection

    fun cancel()

    /**
     * Returns a plan to attempt if canceling this plan was a mistake! The returned plan is not
     * canceled, even if this plan is canceled.
     */
    fun retry(): Plan?
  }

  /**
   * What to do once a plan has executed.
   *

  @Override
  public boolean offer(E e, long timeout, TimeUnit unit) throws InterruptedException {
    return delegate().offer(e, timeout, unit);
  }

  @Override
  public E take() throws InterruptedException {
    return delegate().take();
  }

  @Override
  @CheckForNull
  public E poll(long timeout, TimeUnit unit) throws InterruptedException {
    return delegate().poll(timeout, unit);
  }

   *
   * @param eventClass a class to assert that the returned event is an instance of, or null to
   *     take any event class.
   * @param elapsedMs the time in milliseconds elapsed since the immediately-preceding event, or
   *     -1L to take any duration.
   */
  fun takeEvent(
    eventClass: Class<out ConnectionEvent>? = null,
    elapsedMs: Long = -1L,
  ): ConnectionEvent {

From the list of deployment concepts from above, using workers would mainly help with the **replication** part, and a little bit with the **restarts**, but you still need to take care of the others:

* **Security - HTTPS**
* **Running on startup**
* ***Restarts***