Trying to set up Ruby Rails on Mac

Am trying to set up rails on mac using rbenv and Homebrew.

Currently getting the following message when attempting to 'gem install rails':

ERROR:  While executing gem ... (Gem::FilePermissionError)
    You don't have write permissions for the /Library/Ruby/Gems/2.0.0 directory.
username-mbp:projects username$ gem install rails

Any ideas??


  • This probably means that you used sudoat some point, which means that you run a command that allows you (as a permitted user to execute a command as the superuser or another user) See here:

    Can you please paste the commands you used for installing rbenv, ruby, gem, brew, etc.? Also please paste the output of brew doctorto see if environment is correctly configured for Homebrew. Also, please paste the OSX version and rbenv versionsif rbenv is installed.

    The steps for installing ruby on rails on OSX are:

    1. Install Homebrew by: ruby -e "$(curl -fsSL"`` (as seen here: Run brew doctor and brew updateto see if everything is fine.
    2. Install ruby: OS X comes with Ruby installed (Mavericks/Yosemite even gets version 2.0.0, previously it was only 1.8.7).
    3. Install rbenv: it can be done either by GitHub Checkout or Brew. You probably should use brew. Run brew install rbenv ruby-build(this will also install ruby-build - You can also use this command brew install rbenv ruby-build rbenv-gem-rehash. Then echo 'eval "$(rbenv init -)"' >> ~/.bash_profile (to enable shims and autocompletion). You should problably run this too: echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bash_profile. Close terminal and open it again. Install the preferred version of ruby (if you want): rbenv install 2.0.0-p353.
    4. Install Bundler: gem install bundler.
    5. Install SQLite: gem install sqlite3
    6. Install Rails: gem install rails.

    So, the error you are having is due to permissions (you can understand about them here: Many people suggest fixing the issue with sudo or chown ( I don't recommend that as it messes with system configuration. It will be better that you run:

    rbenv install 2.1.2 
    rbenv global 2.1.2
    gem update --system

    When I run with this error like a year ago, what I did was uninstall everything and start again... but, probably that'll take too long.

    These links might help you: ruby for mac, ruby rbenv, rbenv githube, rubies and gems, question on stack