If you did not know, I use Grav for my website. This is the first CMS that I really enjoyed using. Drupal was too much, WordPress was difficult to hack, and I did not want to bother with anything static since it seemed like too much work. Probably was not, but eh whatever.
Anyway, RSS and Atom feeds are available in the sidebar. However, maybe you want something more fine grained. Filtering by tag? By category? No problem.
Filtering is very easy. Selecting a tag on the side will filter, for example filtering by the tag
radare2 would be /blog/tag:radare2. Replacing
category would filter by categories. To get the RSS feed, replace
blog.atom, depending on what you prefer (tip: use Atom over RSS!).