anchor.diff:  # https://rubygems.org/gems/jekyll-tagging
   # https://rubygems.org/gems/jekyll-tagsgenerator
   # https://rubygems.org/gems/liquid_pluralize
  +# https://rubygems.org/gems/liquid-c
   # https://rubygems.org/gems/stringex
   
   FROM kevinvz/jekyll:4.1.0
   RUN gem install \
  +    jekyll-algolia:1.6.0 \
       jekyll-archives:2.2.1 \
  +    jekyll-commonmark:1.3.1 \
       jekyll-crosspost-to-medium:0.1.16 \
  -    jekyll-feed:0.13.0 \
  +    jekyll-feed:0.15.0 \
  +    jekyll-include-cache:0.2.0 \
       jekyll-last-modified-at:1.3.0 \
       jekyll-mentions:1.6.0 \
       jekyll-paginate:1.1.0 \
  
positive.code:     jekyll-tagging:1.1.0 \
      jekyll-tagsgenerator:0.0.2 \
      liquid_pluralize:1.0.3 \
      stringex:2.8.5 \
      liquid-c:4.0.0 \
      jekyll-include-cache:0.2.0 \
    -- --use-system-libraries
  
  #     jekyll-paginate-v2:1.9.4 \
  
negative.code: # https://github.com/envygeeks/jekyll-docker/blob/master/repos/jekyll/Dockerfile
  # https://rubygems.org/gems/jekyll-algolia
  # https://rubygems.org/gems/jekyll-archives
  # https://rubygems.org/gems/jekyll-commonmark
  # https://rubygems.org/gems/jekyll-crosspost-to-medium
  # https://rubygems.org/gems/jekyll-feed
  # https://rubygems.org/gems/jekyll-include-cache
  # https://rubygems.org/gems/jekyll-last-modified-at
  # https://rubygems.org/gems/jekyll-mentions
  # https://rubygems.org/gems/jekyll-paginate-v2
  