Jekyll Responsive Magick
Jekyll Responsive Magick (jekyll-responsive-magick) is a plugin for Jekyll, a static site generator. It adds filters for setting the srcset, width and height attributes of HTML img tags, and, along the way, automatically resizes images to different widths and heights for different display sizes using ImageMagick. Resized images are cached to minimize build times, and automatically regenerated when the original images change.
The plugin has no dependencies besides the standard ImageMagick command line tools (e.g. convert and identify). This is by design, to make it easy to deploy on services such as Cloudflare Pages where installing extra dependencies onto default container images can be troublesome or impossible.
Instructions for using Jekyll Responsive Magick are available on GitHub. It can be installed from RubyGems. Read more about the motivation and implementation for the work in the blog post.