Instal RVM (use the gpg command from https://rvm.io/rvm/install first):
$ \curl -sSL https://get.rvm.io | bash -s stable --ruby
$ export GEM_HOME="$HOME/.gem"
(add to .zshrc or .bashrc)
$ gem install jekyll bundler
$ bundle install
bundle exec jekyll server
cd path/to/blog
docker run --rm -v $(pwd):/srv/jekyll -it -p 4000:4000 jekyll/jekyll:latest jekyll serve