The FlatSiteBuilder is a very easy to use content management system (CMS) and content creation tool running as a desktop application on Linux.
You are able to build web content which you can host on github pages for free or any other web space provider.
Because all of the pages are beeing build on the desktop it is the fastest content management system available. No code is executed on the web server.
Ubuntu 16.04 tested
chmod +x FlatSiteBuilder-Linux-x86_64-1.5.2.AppImage
ver: 1.5.2 : Nov 08.2017