Install Xcode from the App Store, open it -> Xcode menu > Preferences > Downloads -> install command line tools
curl -L https://get.rvm.io | bash -s stable --ruby
source ~/.rvm/scripts/rvm
start new shell -> ruby -v
test -d ~/zammad/ || mkdir ~/zammad
cd ~/zammad/
curl -L -O http://zammad.org/zammad-latest.tar.bz2 | tar -xj
cd zammad-latest
bundle install
sudo ln -s /usr/local/mysql/lib/libmysqlclient.18.dylib /usr/lib/libmysqlclient.18.dylib # if needed!
rake db:create
rake db:migrate
rake db:seed
rails server # rails web server
ruby script/websocket-server.rb # non blocking websocket server
rails runner 'Session.jobs' # generate overviews on demand, just send changed data to browser