Integration Guide

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.23;

import {ISemaphore} from "@semaphore-protocol/contracts/interfaces/ISemaphore.sol";

interface IHSKPassport {
    function verifyCredential(
        uint256 groupId,
        ISemaphore.SemaphoreProof calldata proof
    ) external view returns (bool);
}

contract MyDApp {
    IHSKPassport public passport;
    uint256 public constant KYC_GROUP = 25; // KYC_VERIFIED

    constructor(address _passport) {
        passport = IHSKPassport(_passport);
    }

    function kycGatedFunction(
        ISemaphore.SemaphoreProof calldata proof
    ) external {
        // REQUIRED: bind proof to caller to prevent front-running attacks
        require(
            proof.message == uint256(uint160(msg.sender)),
            "proof must be bound to caller"
        );
        require(
            passport.verifyCredential(KYC_GROUP, proof),
            "KYC proof required"
        );
        // Your logic here
    }
}

import { Identity } from "@semaphore-protocol/identity";
import { Group } from "@semaphore-protocol/group";
import { generateProof } from "@semaphore-protocol/proof";

// 1. Create identity from wallet signature
const signature = await signer.signMessage(
  "HSK Passport: Generate my Semaphore identity"
);
const identity = new Identity(signature);

// 2. Reconstruct the group (from on-chain events or indexer)
const group = new Group();
for (const member of groupMembers) {
  group.addMember(member);
}

// 3. Generate ZK proof — MUST bind proof to caller (prevents front-running)
const callerAddress = await signer.getAddress();
const proof = await generateProof(
  identity,
  group,
  BigInt(callerAddress),  // message = caller — REQUIRED to prevent front-running
  "mint-silver-v1"        // scope — unique per action for sybil resistance
);

// 4. Submit to your contract (which must also verify proof.message == msg.sender)
const tx = await myDApp.kycGatedFunction(proof);