They offer no name and a graph that you are supposed to take on good faith. In return they expect you to write them (what most would) a cover letter, including probably a resume, and a project you've built in rails that you are proud of.
This is a tremendous amount of information and a effort to expect when they have given very little. By contrast they cannot provide a company name, a legitimate email address, or information on who is running the company.
Granted the graph may be impressive but what about the company culture, location, work space, size, etc? Those seem like more important things to talk about for someone planning to commit the next year or two of their lives to a job.