Ronalds Vilciņš

Syntax highlight with Rouge in Jekyll

Rouge is a popular syntax highlighter written in Ruby to provide the capability of syntax highlighting for code written on html pages. By default, Jekyll 3 and above versions comes with Rouge. It can highlight 100 different languages, and output HTML or ANSI 256-color text. Its HTML output is compatible with stylesheets designed for pygments.

To get syntax highlighting working in Jekyll, we need to enable the Rouge syntax highlighter. Open the _config.yml file and add the following line:

highlighter: rouge

If you’re still using Jekyll 2, then open your terminal and enter the following command:

gem install rouge

Rouge is compatible with the Pygments syntax highlighter, which means that we can use themes created for Pygments. You can preview themes here. Once you found your favourite theme, view the page source to find it and copy or save it to your site css file.

Pygments themes uses .syntax as the default class, so you will need to replace the .syntax with .highlight class in the pygments.css file or change the default .highlight css class name to .syntax in the Jekyll’s _config.xml file like this:

markdown: kramdown
highlighter: rouge
  input: GFM
    default_lang: html
    css_class   : 'syntax'