I tried doing number 3 about two weeks ago with the intention of enabling TollGates to resell each other's Internet gateways. The router's resources are much too limited for CDK or cashu-cli though. Now I'm using an endpoint that melts cashu tokens to LNURL.
Eventually the router's need a way to issue payments as well though...
an app based on CDK should compile to a tiny binary, it might work after all. is the wallet going to be for the router or for the user? if for the user, it should live in the browser frontend.
Currently I'm thinking of a wallet that sits on the router so that the router can shop for cheaper and better gateways. However, the user who buys data from the router might also benefit from a customeized wallet that keeps lots of small notes offline and automatically pays in small installments.
The router I'm working on (GLAR300m) usually has between zero and 500kb or remaining storage space. There is probably a lot of room for optimization though...
