jekyll-picture-tag

https://github.com/robwierzbowski/jekyll-picture-tag

Jekyll Picture Tag is a liquid tag that adds responsive images to your Jekyll static site. It follows the picture element pattern, and polyfills older browsers with Picturefill. Jekyll Picture Tag automatically creates resized source images, is fully configurable, and covers all use cases — including art direction and resolution switching — with a little YAML configuration and a simple template tag.