This method is now outdated. Github Pages now exposes the site.github namespace
I use jekyll with github pages to build this blog. I also use disqus for comments.
You just have to add a code snippet into the page.
Problem is when developing with jekyll I usually like to test how things look locally and then push the site to github pages. Which means whenever I look at a blog post I haven’t pushed, Disqus will create a thread like localhost:4000/something.html in addition to the intended one morenoh149.github.io/something.html. I asked around and found a jekyll plugin for environment variables. But github pages disables plugins. So I dug through the site variable on both production and github pages and found github pages sets GH_ENV which I haven’t seen documented anywhere. Now I simply do
{% if site.GH_ENV == 'gh_pages' %}
< disqus snippet >
{% endif %}to get the disqus thread generated only if the post is being viewed on github pages.
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