You might wonder about this request in your test.log:

Started GET "/__identify__" for 127.0.0.1 at 2015-04-29 18:00:02 +0100

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This is what happens: For drivers like Selenium, Capybara will boot up a Thin or Webrick server in a separate thread. It then makes a GET request to /__identify__ to see if the server is ready to accept requests.

Since you don't have a route that responds to /__identify, Capybara will wrap your Rails app in a middleware Show archive.org snapshot that responds to that path.