In Poltergeist mode or headless mode, it is different from Selenium since there is no browsers which you can track failure visually. The advantages of Poltergeist are: it is faster, it demands less source when we compare to Selenium, and eventually it is more suitable for Continues Integration (CI). Installation and further information about Poltergeist you can visit git page . Running Capybara with terminal may help you to get quick result. By this way you can check if button, field, or any object can be reachable easily and this method may help you to reduce failure issue on your CI and get you more realistic results. You can just paste the following commands into your terminal, it will go to home page of Amazon.
Not a feature, but the future of an app is under testing.