Jekyll has a plugin system with hooks that allow you to create custom generatedcontent specific to your site. You can run custom code for your site withouthaving to modify the Jekyll source itself.
You can add specific plugins to the whitelist key in _config.yml to allow them to run in safe mode.
Installation - How to install plugins Your first plugin - How to write plugins Generators - Create additional content on your site Converters - Change a markup language into another format Commands - Extend the jekyll executable with subcommands Tags - Create custom Liquid tags Filters - Create custom Liquid filters Hooks - Fine-grained control to extend the build process