https://help.github.com/articles/using-jekyll-as-a-static-si...
There's a link to the source in the footer: https://rcoh.me
The package is ox-hugo: https://ox-hugo.scripter.co/
In fact, that site is dog-fooding ox-hugo.. I simply commit the Org files, and Org --ox-hugo--> Markdown --hugo--> HTML conversion happens on Netlify, and that site gets updated.
Github repo: https://github.com/kaushalmodi/ox-hugo/
My posts exist in a repository in the content/posts folder as markdown files. When I push to master, it kicks off a CircleCI build that generates all the HTML and pushes that to the gh-pages branch of the same repo.
Repo: https://github.com/seangransee/blog Final result: http://blog.seangransee.com
Github also supports Jekyll directly.