rbenv

git clone https://github.com/rbenv/rbenv.git ~/.rbenv
git clone https://github.com/rbenv/ruby-build.git ~/.rbenv/plugins/ruby-build
cd ~/.rbenv && src/configure && make -C src
echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bash_profile
~/.rbenv/bin/rbenv init

gem sources -r https://rubygems.org/
gem sources -a https://ruby.taobao.org
gem sources -a http://mirror.sysu.edu.cn/rubygems