Installing Jekyll after El Capitan update

A short update on how I recently resolved installing and running Jekyll since updating my Mac to El Capitan

Using Terminal or the command line to install anything is just great when things go smoothly however more often than not a certain dependency is missing or a recent update elsewhere has conflicted with whatever it is you were running perfectly fine before.

And so to the issue

Upon trying to install/reinstall Jekyll I got this error message:

ERROR:  While executing gem ... (Errno::EPERM)
Operation not permitted - /usr/bin/jekyll

Solution

The recent increased security changes in OS X El Capitan (called System Integrity Protection) now mean that in order to install Jekyll we need to explicitly specify a directory which isn't protected by this. The default location for installation is the Ruby > Gems directory however it's protected now. Therefore we specify a local directory:

sudo gem install -n /usr/local/bin jekyll

Likewise the same command can be used for installing other Ruby Gems where this problem occurs.