Anonymous voting using Semaphore + Polygon ID

This project demonstrates a basic implementation for anonymous voting. It uses Polygon ID for authentication and Semaphore for anonymous voting.

This was done as a project at the Polygon @ The Pit Hackathon. It is a collaboration effort between @shuklaayush and @flyingnobita

Demo

zkvote_demo.mp4

System Architecture

How to run

Install dependencies

yarn install

Setup

Environment variables

Copy the packages/contracts/.env.example file to packages/contracts/.env and fill in the values.

MNEMONIC=
RPC_MUMBAI_URL=
ETHERSCAN_API_KEY=
PAGEKITE_SUBDOMIAN=

Polygon ID

1. Go to https://platform-test.polygonid.com and create a claim schema with a single attribute:

Reputation: number

2. Generate QR code to issue claims and send to claimers.
3. Install the Polygon ID app on mobile and scan the QR code on the Polygon ID app to issue a claim to yourself.
4. Add details of the claim schema and issuer to packages/contracts/scripts/polygon-id-constants.json file.

Metamask mobile

1. Install the Metamask mobile app and create a new wallet.
2. Add the pagekite address (https://${PAGEKITE_SUBDOMAIN}.pagekite.me) as a custom RPC network.

Steps

1. Instantiate a local fork of the Polygon Mumbai testnet, deploy semaphore contracts and create a dummy poll.

# Spawn a local forked network
yarn localnode
# Deploy semaphore contracts and create a dummy poll
yarn deployLocalnode

This also initiates a tunnel to the local server at https://${PAGEKITE_SUBDOMAIN}.pagekite.me using pagekite.

2. Start the web-app showing the proposal and voting choices.

yarn react

3. Scan the QR code on the webpage using the Polygon ID app. This generates a proof for the claim in your Polygon ID wallet and initiates a transaction to add yourself as voter.

4. Verify the nonce on Metamask mobile for the transaction, bump up the gas limit to at least 4 million and send the transaction.

5. Start the poll by running

yarn startPoll

6. Connect your metamask mobile to the web-app via Wallet Connect.

• Click connect on the frontend and wait for the wallet connect QR code to pop-up.
• Scan it on the Metamask mobile app to connect. Click connect again to see on the signer address that it's connected.

7. Initiate the voting transaction by clicking on a choice. Verify the nonce on Metamask mobile and sign the transaction.

8. Wait for the transaction to be mined and the count to be updated on the frontend.