title: Reliably detecting PhantomJS-based spam bots
body: <p>Is there any way to consistently detect PhantomJS/CasperJS? I've been dealing with a spat of malicious spambots built with it and have been able to mostly block them based on certain behaviours, but I'm curious if there's a rock-solid way to know if CasperJS is in use, as dealing with constant adaptations gets slightly annoying.</p>
  
  <p>I don't believe in using Captchas. They are a negative user experience and ReCaptcha has never worked to block spam on my MediaWiki installations. As our site has no user registrations (anonymous discussion board), we'd need to have a Captcha entry for every post. We get several thousand legitimate posts a day and a Captcha would see that number divebomb.</p>