How do you decide how much to spend? Does the NFC tag only reveal as much as minimally needed?
I did it!
I can now issue a record (credential) to a NFC tag associated with a #nostr #safebox.
So I've proven I can have a fully functional wallet with only a NFC tag.
I can:
1. Pay to NFC Tag
2. Pay from NFC Tag
3. Present a record (i.e., prove) using a NFC Tag
4. Accept a Record using a NFC Tag.
and of course,
5. Login with a NFC Tag.
IMHO, this is BIG! It's now possible to have a wallet that exists independently of a phone, and which can be used with a super cheap NFC Tag.
Onward!
https://video.nostr.build/af0fcb97d28f770f72597039a937deccb7b313e3e8de8becd0e58e89122fbf25.mp4
Discussion
I encode a default tip amount (21 sats) if no amount is specified by the acquiring app. The info is encrypted and can only be decrypted by the vault that did the issuance. Also, the vault needed to ‘trust’ the acquiring instance (known public key) before it does anything.