I created the website, to build cumulative flow diagrams from boards.
The site was created quickly one weekend to help visualise the work that the team I was part of was working on. Since then it has started to be used by many people, unfortunately I do not have the time to add the new features requested (at least not quickly!).
Recently a few people have contacted me to ask about and if they are able to help implement them, the code is now available on and open for Pull Requests, so if you would like to see how it works, or add any new functionality please check it out and if there is anything I can do to help.
I will be adding more features when I get the time, and the latest release includes the ability to export boards to CSV thanks to for adding this in!