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VGDP — Zero-Knowledge Gig Delivery Proof

Prove a delivery happened without revealing where the rider was.

Sole developerMay 2026Blockchain

// why: Disputes shouldn't cost riders their location privacy.

$ cat projects/vgdp-zk-delivery-proof.md

TL;DR

  • Prove radius, hide location: Groth16 ZK proof, no GPS on-chain
  • Dispute-ready: registry + resolver + reputation contracts
  • Integrates: rider SDK + OpenAPI with Swiggy-style example

// what does it do?

Privacy-preserving delivery proof for gig riders. Prove you were inside the delivery radius with a Groth16 ZK proof — only hashes touch the chain, never GPS.

// why this project?

Delivery disputes today require exposing rider GPS trails, which is both a privacy violation and a central point of data abuse.

// what broke / learned

Circom constraints humbled me — radius math is simple until it's a circuit.

// results

  • Solidity contracts (proof registry, dispute resolver, reputation) targeted at Polygon with Foundry, a Circom Groth16 circuit for radius proofs, a TypeScript off-chain validator service, a React Native SDK for rider apps, and an OpenAPI 3.0 spec with a Swiggy-style example integration.
Groth16 ZK circuitPolygon testnet contractsNo GPS ever touches the chainRider SDK + OpenAPI spec

Tech stack

SolidityCircomGroth16PolygonTypeScriptReact NativeFoundry
VGDP — Zero-Knowledge Gig Delivery Proof | Mrinall Samal