Cashu is great. The only thing I don’t like is that Carol needs to trust Alice’s mint. I understand that this is the constraint to make the tokens pure data, but it feels awkward that Carol needs to trust all the mints of all the users that send her money.
peer to peer ecash transactions in a nutshell
1 - alice sends ecash token to carol
2 - carol sends ecash to bob the mint
3 - bob verifies and checks for double-spending
4 - bob issues a new token to carol
like physical cash, step 1 is instant and works without internet. https://blossom.primal.net/5acf53584ac8a5487246983896055066968d2316c35f22e4ff5a454954e8055f.mov
Discussion
Carol could run a mint
Carol can instantly exit Alice's mint via LN
Unless Carol is offline, there is a little risk
If Carol doesn't trust Alice or any other mint operator, they can show an LN invoice and still get sats from the counterparty
meow
Cashu is a trust-based custodial system. All users need to trust the mint. The benefit is privacy, ease of use, and censorship resistance. The mint can only rug everyone or no one (you can’t be singled out and rugged or censored as an individual user).