Woah, nice! You're much further ahead than I am. Good luck!
The bananas are really cool, but they distract from reading :D
I really wish we could get a privacy-respecting standard for electronic receipts. But every time a shop experiments with it, it's using a shitty app which they use to track their customers.
Each electronic payment should have an attached PDF invoice. That would be a great start.
I imagine that would lead to even more data mining by banks and payment processors. Two entities who already get access to way too much data.
I assume everyone except myself already has this info... Unfortunately
apparently that will be soon required in Malaysia. And they use a OASIS standard