Source Code
Reading the source
The code in the repository resides in one file, written in Literate CoffeeScript.
Changing the source
If you don't like that language, you can always compile it directly to JavaScript with the following command.
coffee --compile first-order-matching.litcoffee
This assumes that you've installed CoffeeScript and have the source file accessible.
Importing the source
To import the source into your project, you can include it directly from a CDN at this URL. There is a source map file in the same folder that your browser should detect.