Currently, only Ruby 2.1 is supported. h4(#rvm). *Option 1: Install with RVM*
sudo gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3
\curl -sSL https://get.rvm.io | sudo bash -s stable --ruby=2.1
sudo adduser "$USER" rvm
Either log out and log back in to activate RVM, or explicitly load it in all open shells like this:
source /usr/local/rvm/scripts/rvm
Once RVM is activated in your shell, install Bundler:
~$ gem install bundler
h4(#fromsource). *Option 2: Install from source* Install prerequisites for Debian 7 or 8:
sudo apt-get install \
    bison build-essential gettext libcurl3 libcurl3-gnutls \
    libcurl4-openssl-dev libpcre3-dev libreadline-dev \
    libssl-dev libxslt1.1 zlib1g-dev
Install prerequisites for CentOS 6:
sudo yum install \
    libyaml-devel glibc-headers autoconf gcc-c++ glibc-devel \
    patch readline-devel zlib-devel libffi-devel openssl-devel \
    automake libtool bison sqlite-devel
Install prerequisites for Ubuntu 12.04 or 14.04:
sudo apt-get install \
    gawk g++ gcc make libc6-dev libreadline6-dev zlib1g-dev libssl-dev \
    libyaml-dev libsqlite3-dev sqlite3 autoconf libgdbm-dev \
    libncurses5-dev automake libtool bison pkg-config libffi-dev
Build and install Ruby:
mkdir -p ~/src
cd ~/src
curl http://cache.ruby-lang.org/pub/ruby/2.1/ruby-2.1.6.tar.gz | tar xz
cd ruby-2.1.6
./configure --no-install-rdoc
make
sudo make install

sudo gem install bundler