HonkDrop

Screenshots

Problem Statement

Did I hear "Drop"? AirDrop?That's right. But because you heard AirDrop doesn't mean you'll remain safe when claiming it.This app allows you to claim an airdrop for which you're eligible using a stealth address (A.K.A. a fresh account, not connected to the eligible account).Because you can use any kind of key, you can literally airdrop tokens to EthGlobal's participants wearing the Arx Wristband. You can send a payload, get thesecp256r1signature, and verify that signature inside the circuit without revealing its wearer.You see, I built this in a day. But it took thousands of engineering hours to get here. Totally worth it. You can use the same primitive to:create gated chatrooms without revealing identityprovide privacy and safety to children by using the wristband as identifier/payment methodof course airdrop tokens or POAPs to everyone that was present on a physical place without doxxing themincrease whistleblower's privacy and safetyyou get the point by now

Solution

I was more like building first and figure out the rest later on. But so far I was pretty sure I needed these technologies:Arx: for the wristbands, this is where I started figuring out the ideaStealthdrop: a famous app by 0xParc, which is NOT safe because ECDSA signatures are malleable and cannot be used as nullifiersPLUME nullifiers: a solution to the above problem, designed by @Divide-By-0 et al, and that prompted quite some development from Aztec Labs, Distributed Labs, and other engineers, in order to generate a good, fast Noir implementationNoir React Native: an amazing starter by @madztheo with a ton of primitives you can use to prove quickly on mobile phones using NoirNoir: duhEVM chains such as Gnosis (L1s) and Scroll (L2s), and I would also try the Bitcoin L2 despite being unsure if it could be deployed there (needs all the bn254 precompiles)