> For the complete documentation index, see [llms.txt](https://trustlevel.gitbook.io/knowledge-base/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://trustlevel.gitbook.io/knowledge-base/tools-and-apps/zk-voting-app.md).

# ZK Voting App

Anonymous, verifiable voting on Cardano. Voters prove they belong to an authorised group and cast a ballot **without anyone — not even the organiser — being able to link the vote back to them**, while every vote is tallied immutably on-chain.

> **Status: Preview · Public test live** The application is deployed and open for public testing on the **Cardano Preprod Testnet**. No real funds are involved — voting uses free test ADA. This is a preview release; expect testnet-only behaviour and occasional changes.

**Try it:** <https://vote.trustlevel.io>

***

### What makes it different

* **Anonymous** — votes are cast with a zero-knowledge (Semaphore / Groth16) proof of group membership. The proof confirms you are an eligible voter without revealing *which* voter.
* **One vote per person** — a one-time cryptographic nullifier makes double voting impossible.
* **Closed group** — only invited participants can vote.
* **Publicly verifiable** — the final tally lives on the Cardano blockchain and cannot be altered.

Two voting modes: **Simple** (one vote for one option) and **Weighted** (distribute a fixed number of points across options).

***

### Before you start (one-time setup)

Because this is a testnet preview, you need a Cardano wallet set to **Preprod** and some free test ADA:

1. **Install a CIP-30 wallet** browser extension — [Eternl](https://eternl.io/), [Lace](https://www.lace.io/), or [Yoroi](https://yoroi-wallet.com/).
2. **Switch the wallet network to Preprod** (testnet), not Mainnet.
3. **Get free test ADA** from the [Cardano Testnet Faucet](https://docs.cardano.org/cardano-testnets/tools/faucet) — paste your wallet's Preprod address and request funds. A few test ADA is enough to cover transaction fees.

***

### For Organisers (Admins)

You set up and run a voting event end to end.

1. **Create the event** — connect your wallet at [vote.trustlevel.io](https://vote.trustlevel.io) and enter the event name, the options voters choose from, the voting mode (simple or weighted), and set the voting start/end dates (must be at least \~15 minutes in the future).
2. **Invite participants** — add people by wallet address or email. Each invitee gets a unique private link. The group is closed: only invited people can register and vote.
3. **Wait for registration** — invitees open their link and register. Their browser generates a private cryptographic identity locally; only a public commitment is added to the group. No personal data is collected.
4. **Deploy on-chain** — once the participant list is final, publish the event on the blockchain: Two transactions anchor the voting contracts on Cardano. From here, options, dates, and group membership are **immutable**.
5. **Read the results** — when voting closes, the tally is publicly readable on-chain. You see the totals only — never who voted for what.

***

### For Voters (Participants)

1. **Open your invitation link** in a browser that has a Preprod-configured Cardano wallet (see setup above).
2. **Register** — connect your wallet and confirm. Your browser creates a Semaphore identity: two secret values that **never leave your device**. Only a public commitment is sent to the group.
3. **Wait for the voting window** — the event has a fixed start and end enforced by the blockchain.
4. **Vote** — during the window, pick your choice and submit. Your browser silently generates a zero-knowledge proof of membership, computes a one-time anti-double-vote nullifier, and submits the transaction. No one can link the vote back to you.
5. **See results** — once the event ends, the tally is public and final on-chain.

***

### Links

|                                |                                                          |
| ------------------------------ | -------------------------------------------------------- |
| Live application               | <https://vote.trustlevel.io>                             |
| Source code (GitHub)           | <https://github.com/TrustLevel/ZK-Voting-App>            |
| Testnet faucet (free test ADA) | <https://docs.cardano.org/cardano-testnets/tools/faucet> |
| Semaphore protocol             | <https://semaphore.appliedzkp.org/>                      |

***

### FAQ

**Is this real money?** No. It runs on the Cardano **Preprod Testnet** with free test ADA.

**Can the organiser see how I voted?** No. The system is designed so that no party — organiser, server, or blockchain observer — can link a vote to a voter.

**Can I vote twice?** No. A one-time nullifier derived inside your zero-knowledge proof blocks any second vote, without ever revealing your identity.

**What if I lose my wallet/identity?** Your voting identity is derived from your wallet on your device. Keep access to the same wallet you registered with for the duration of the event.