Poltergeist vs Kahlan: What are the differences?
What is Poltergeist? A PhantomJS driver for Capybara. Poltergeist is a driver for Capybara. It allows you to run your Capybara tests on a headless WebKit browser, provided by PhantomJS.
What is Kahlan? A full-featured Unit & BDD test framework. It is a full-featured Unit & BDD test framework a la RSpec/JSpec which uses a describe-it syntax and moves testing in PHP one step forward.
Poltergeist and Kahlan can be categorized as "Testing Frameworks" tools.
Poltergeist and Kahlan are both open source tools. Poltergeist with 2.54K GitHub stars and 439 forks on GitHub appears to be more popular than Kahlan with 1K GitHub stars and 54 GitHub forks.