ruby-slim binary package in Ubuntu Focal arm64

 Slim is a template language whose goal is to reduce the view syntax to the
 essential parts without becoming cryptic.
 .
 A short list of the features:
  - elegant syntax: short syntax without closing tags, HTML style mode with
    closing tags and configurable shortcut tags
  - automatic HTML escaping and support for Rails' `html_safe?`
  - highly configurable and extendable via plugins: logic less mode similar
    to Mustache and translator/I18n support among others.
  - high performance: comparable speed to ERB and streaming support in Rails
  - supported by all major frameworks (Rails, Sinatra, ...)
  - full Unicode support for tags and attributes on Ruby 1.9
  - embedded engines like Markdown and Textile

Source package