install tools required for civihr / buildkit

buildkit-setup.sh

    echo "mysql-server-5.5 mysql-server/root_password password root" | sudo debconf-set-selections
    echo "mysql-server-5.5 mysql-server/root_password_again password root" | sudo debconf-set-selections
    sudo apt-get update
    sudo apt-get install -y \
      curl \
      vim \
      man-db \
      mysql-server \
      git \
      php5 \
      unzip \
      zip \
      php5-curl \
      mcrypt \
      php5-mcrypt \
      php5-mysql \
      php5-gd \
      php5-imap \
      php5-intl \
      php5-xdebug
    curl -sL https://deb.nodesource.com/setup_5.x | sudo -E bash -
    sudo apt-get install -y nodejs
    sudo php5enmod mcrypt intl imap gd
    sudo npm install npm -g
    git clone https://github.com/civicrm/civicrm-buildkit.git /home/$SSH_USER/buildkit
    cd /home/$SSH_USER/buildkit/bin/ && ./civi-download-tools
    echo export PATH="/home/$SSH_USER/buildkit/bin:\$PATH" >> /home/$SSH_USER/.bashrc
    echo "Include /home/$SSH_USER/.amp/apache.d/*.conf" | sudo tee -a /etc/apache2/apache2.conf
    sudo a2enmod rewrite

$SSH_USER isn't specified

Ah, sorry - this was just copied from the Vagrantfile I'm using and it specified $SSH_USER as an environment variable