Impact JS Weltmeister Editor API implemented in Ruby. Please refer to Impact.js Getting Started
Have Ruby and Rubygems running on your system (tested with ruby 1.9.3).
run gem install sinatra
Copy impact.rb into your project directory.
Either remove lib/weltmeister/api (you can just rename it, if you want) or alter your lib/weltmeister/config.js to remove all mentions of .php.
change into your project dir and doubleclick impact.rb
(alternatively you may start it from the console like this: ruby impact.rb)
Point your web browser to http://localhost:4567/weltmeister