Is this entirely based on trust? What guarantees the relay will perform the requested operations?
Does the user pay after the relay performs the operation? If so, the relay is trusting the user to pay…
Discussion
Vending machines were used as an analogy for smart contracts because they do not require trust. It is an atomic exchange, unlike this NIP.
During the live stream, when i pointed out this might need a reputation system, he suggested the vendor would have to figure that out via another system.
🤦♂️
Reputation scales poorly compared to the atomicity of a real smart contract. This is why we’ve been working on Sats4Files to swap data for files off-chain over Lightning like a real vending-machine.
If we aren’t reducing trust, then we’re all just LARPing here.
If you’re interested in making this like a real vending machines for services (beyond requesting files like Sats4Files), I would explore the S in ZKCSP: https://eprint.iacr.org/2017/566
They provide a way to pay for services in an atomically trust-minimized way, without either party trusting each other — but it doesn’t work over Lightning yet like Sats4Files.
Not via another system; at the margins.