Can't install bundler using gem I'm trying to install Bundler on my Mac which is running OS X El Capitan Public Beta 6 (15A278b).

I try sudo gem install bundler but I get the following error back


  ERROR: While executing gem ... (Errno:EPERM)
      Operation not permitted - /usr/bin/bundle
For future reference, use a newer version of bundler - disabling a core security feature of the operating system is a Bad Idea and will leave your machine vulnerable.