Speed is to be considered as a feature!

To increase the "reactivity" of a website there isn't a magic solution but rather a combination of tuning options with different levels of impact and difficulties of implementation. A good place to start reading would be this wiki page.

While it is the most demanding approach,  Varnish works well for websites with lots of traffic. There are some extensions available on the TER integrating Varnish with TYPO3.

For the needs of the Bootstrap Package, the extension "static file cache" has been installed and configured. It transparently caches pages as static HTML. Using mod_rewrite and mod_expires improves the response times by a factor of 230! Cache pages get automatically reset when content is updated in the Backend by a user. Notice, the .htaccess file, contained in the document root, contains some special rules for dealing with static pages versus dynamic pages.