   Next we create our environment as always. However, we add
        <code class="literal">DB_PRIVATE</code> to our environment open flags. This
        flag causes our environment to back regions using our
        application's heap memory rather than by using the filesystem.
        This is the first important step to keeping our DB data
        entirely in-memory.
    </p>
      <p>
        We also remove the <code class="literal">DB_RECOVER</code> flag from the environment open flags. Because our databa