I second Hugo as a static website generator. I've been using Jekyll for a long time, but it is just too slow for a nice workflow, especially as the site/blog grows to more than a handful of pages.

Hugo is blazingly fast, has a very active community and has all the features you need. Also it's just a single binary and very easy to use.

You could use a CI system like Travis CI or Gitlab CI to automatically build the site and deploy it to a preview website on pushes.