The first to implement a pure-ruby HTML renderer was Markaby[1]. This was without the reactive bits. I remember it being quite enjoyable to use. The barrier bet

The first to implement a pure-ruby HTML renderer was Markaby[1]. This was without the reactive bits. I remember it being quite enjoyable to use. The barrier between ruby logic and HTML rendering is much lowered. The main downside is that rendering wasn't very efficient as it has to execute thousands of ruby functions per page. One per DOM node. This makes it harder to cache fragments as both the code and HTML is now inter-mingled. [1]: https://rubygems.org/gems/markaby https://rubygems.org/gems/markaby