Hello World Jekyll Plugin

hello-world.rb

module Jekyll
  class HelloWorld < Liquid::Tag

    def initialize(tag_name, text, tokens)
      super
      @text = text
    end

    def render(context)
      "Hello World, #{@text}!"
    end
  end
end

Liquid::Template.register_tag('hello', Jekyll::HelloWorld)

Save this file in _plugins and add {% hello Jesse %} to a markdown file or template. Then run bundle exec jekyll serve and navigate to the page. Based on the Jekyll docs.