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Cuprite is a driver for Capybara that uses Ferrum — a minimal-dependency pure-Ruby driver for running headless Google Chrome instances. Cuprite gives you all the benefits of Ferrum, but without the overheads of having to switch APIs. The API aims to have an API consistent with Poltergeist's where it's reasonably able to control the browser. You can also get access to the underlying Ferrum instance for full control in your tests, for example: navigation, debugging, script execution, DOM manipulation, screenshot generation, traffic analysis, and complete fine-grained mouse and keyboard event synthesis.