Jekyll style guide

Your site should have a .gitignore file, with a minimum of the following Git-ignored paths, which are local, unversioned artifacts created during the Jekyll build process:

_site
.sass-cache
.jekyll-metadata

Gemfile.lock

If the built site is served via GitHub Pages, you should also add Gemfile.lock to your site’s .gitignore. The github-pages gem strictly versions dependencies, rendering versioning the lockfile unnecessary, and potentially could result in using outdated gem versions.