It's another version of GhoSadillaX, the theme of Ghost.
Copy _config.sample.yml to _config.yml.
And edit the subjects.
Create two folders under your source directory: tags and categories.
Create an index.md file under each folder that you've just created.
tags/index.md:
layout: tags
title: tags
---categories/index.md:
layout: categories
title: categories
---Register your own duoshuo account and replace duoshuo short_name in _config.yml.