To use (updated) jekyll:
gem install jekyll bundler
Prepare jekyll and its dependencies:
bundle install
To build and deploy after changes run the following in the source branch:
make deploy
which will do the following:
bundle exec jekyll build
git checkout master
cp -rf _site/* ./
rm -rf _site
git add -A .
git commit -m "updates to website"
git push origin master
git checkout source