I've been meaning to host something like this. Tried to do it with wallabag, but couldn't be arsed to set-up and SMTP server just for the confirmation email.
I think it would be great if you could add more screenshots to the documentation. Beyond the landing page, I couldn't see how the bills look once generated, or how to generate one.
You mean, the one where people immediately exchanged their free crypto for USD as soon as they got it?