You can use Github Pages for deploying moonwalk for free.
If you are deploying Moonwalk on Github Pages, I recommend forking Moonwalk and change the dependency (in
moonwalk.gemspec&_config.yml) fromjekyll-soopr-seo-tagtojekyll-seo-tag- Github Pages only allow a specific list of gems to be installed.
If you want to use this theme for your Jekyll's site deployed on GitHub Pages, follow the instructions on this page.