🕶️ UniCloak

A Unified, Compliance-Aware Privacy Layer for Blockchain

UniCloak is a zero-knowledge powered privacy protocol that enables users to transact, swap, and move stablecoins privately across chains from a single liquidity pool, while remaining compliance-aware by design.

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🚨 Problem

Public blockchains are transparent by default.

• Every transaction is traceable
• Wallet histories reveal behavioral patterns
• Sensitive use cases like:
  • Payroll
  • Donations
  • Treasury management
  • Trading strategies
    become fully exposed

Existing privacy solutions fail because they:

• Stop at withdrawals
• Break composability with DeFi
• Are non-compliant and legally fragile
• Fragment liquidity across chains

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💡 Solution

UniCloak decouples fund ownership from fund usage using Zero-Knowledge Proofs, enabling private yet verifiable transactions without fragmenting liquidity.

At its core, UniCloak provides:

• Private identity verification
• Private DeFi execution
• Unified liquidity on a single chain
• Cross-chain access without breaking privacy

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🧠 How UniCloak Works (High Level)

1. ZK Identity (zk-KYC)
   Users generate a privacy-preserving identity commitment from government-issued documents (e.g. passport), without revealing personal data on-chain.

2. Private Wallet Commitments
   Wallets are represented as cryptographic commitments (Poseidon hash), not public addresses.

3. Unified Private Pool
   Stablecoins (e.g. USDC) are deposited into a shared private pool anchored on Mantle.

4. ZK-Verified Actions via Relayers
   Withdrawals, swaps, bridges, and cross-chain swaps are executed by relayers using ZK proofs — the user’s wallet is never revealed.

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🧩 Architecture Overview

flowchart LR
    U[User Browser]

    subgraph ZKID["zk-ID Layer"]
        P[Passport Upload]
        MRZ[MRZ Extraction Local]
        IC[Identity Commitment Poseidon Hash]
        IM[Identity Mixer Merkle Tree]

        P --> MRZ
        MRZ --> IC
        IC --> IM
    end

    subgraph WALLET["Private Wallet Layer"]
        ZKIDP[ZK Proof of Identity]
        WC[Wallet Commitment Poseidon Hash]

        ZKIDP --> WC
    end

    subgraph POOL["Unified Private Pool Mantle"]
        MT[Wallet Commitments Merkle Tree]
    end

    subgraph RELAYER["Relayer Layer"]
        R[Relayer]
    end

    subgraph DEFI["In Protocol DeFi Execution"]
        WOOFI[WooFi Swap]
        STG[Stargate Bridge]
        XM[Cross Messenger]
        REC[Recipient]
    end

    IM --> ZKIDP
    WC --> MT

    U -->|Deposit with ZK Proof| MT
    MT -->|ZK Proof| R

    R --> WOOFI
    WOOFI --> REC

    R --> STG
    STG --> REC

    R --> STG
    STG --> XM
    XM --> WOOFI
    WOOFI --> REC

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1️⃣ zk-ID Creation (Identity Layer)

• User uploads a passport image in the web app.
• Passport data (MRZ fields) is extracted locally in the browser.
• Frontend generates a random secret.
• An identity commitment is created using a cryptographic hash of:
  • passport data
  • secret
• The identity commitment is submitted to the Identity Mixer contract and stored in a Merkle Tree.

No raw passport data is stored on-chain.

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2️⃣ Private Wallet Creation

• User creates a wallet commitment instead of a public address.
• Wallet commitment is derived from:
  • random nullifier
  • user secret
  • initial balance = 0
• User submits a ZK proof of identity ownership.
• Wallet commitment is stored in the Private Pool contract’s Merkle Tree.

Wallets are anonymous commitments, not EOAs.

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3️⃣ Deposit Flow

• User deposits stablecoins (e.g. USDC) into the private pool.
• User generates a ZK proof proving:
  • ownership of a valid zk-ID
  • ownership of a valid wallet commitment
• A new wallet commitment with updated balance is computed.
• Old commitment is invalidated and the new one is added to the pool Merkle Tree.

Balance updates happen via commitment replacement.

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4️⃣ Private Withdrawal

• User generates a ZK proof proving sufficient balance.
• Proof is sent to a relayer instead of submitting directly.
• Relayer submits the transaction on-chain.
• Funds are transferred to the recipient without revealing:
  • deposit source
  • wallet identity

This breaks the on-chain link between deposit and withdrawal.

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5️⃣ Private Swap

• User requests a swap (e.g. USDC → another asset).
• ZK proof authorizes the operation.
• Relayer executes:
  • Private Pool → WooFi → Recipient
• User identity and wallet remain private.

Privacy extends into DeFi execution.

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6️⃣ Private Bridge

• User requests a bridge to a destination chain.
• ZK proof authorizes the transfer.
• Relayer executes:
  • Private Pool → Stargate → Destination Chain Recipient
• No wallet linkage is revealed on either chain.

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7️⃣ Private Cross-Chain Swap

• User specifies:
  • destination chain
  • target token
  • slippage constraints
• ZK proof authorizes execution.
• Flow:
  1. Private Pool → Stargate
  2. Funds bridged to destination chain
  3. Cross Messenger receives funds
  4. WooFi swap on destination chain
  5. Funds delivered to recipient

Single liquidity pool with private multi-chain execution.

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🔐 Core Design Principles

• Privacy by default
• Unified liquidity (no fragmentation)
• In-protocol DeFi composability
• Compliance-aware identity proofs
• Relayer-based execution for unlinkability

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🔐 zk-KYC (Current Demo vs Vision)

✅ Current Demo

• Passport MRZ scanned locally in the browser
• Identity commitment generated using passport data + secret
• Demonstrates end-to-end ZK identity flow

⚠️ Limitation:
This demo does not verify passport authenticity — data could be tampered.

🚀 Vision

• Use biometric passports (ePassports) with NFC
• Verify Document Security Object (SOD) using ICAO PKI
• Cryptographically prove the passport is genuine
• Generate ZK proofs entirely on-device
• No personal data ever leaves the user’s machine

This enables real, cryptographically verifiable zk-KYC without surveillance.

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📁 Project Structure

unicloak/
├── contracts/src/
│   ├── identityMixer/
│   │   ├── Mixer.sol        # zk-ID Merkle tree & identity commitments
│   │
│   ├── pool.sol             # Unified private liquidity pool
│   │
│   ├── cross-messenger.sol  # Cross messenger contract on destination chain for receiving bridged funds               
│   │
│   └── interfaces/
│       ├── IWooFi.sol                # WooFi swap interface
│       ├── IStargate.sol             # Stargate bridge interface
│
├── circuits/
│   ├── identity/src/
│   │   └── main.nr           # zk-ID circuit (passport → commitment)
│   │
│   ├── deposit/src/
│   │   └── main.nr           # Deposit proof circuit
│   │
│   ├── withdraw/src/
│   │   └── main.nr           # Withdraw proof circuit
│
├── frontend/                 # ui
│
├── relayer/
│   ├── index.ts                      # Relayer entry point, executes tx on behalf of users
│
├── merkleTreeManager/                # off-chain merkle tree manager for providing merkle proofs for commitments

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🛠️ Tech Stack

• Zero-Knowledge Circuits:
  Noir — used for zk-ID, wallet creation, deposits, withdrawals, and cross-chain authorization proofs.

• Smart Contracts:
  Solidity — identity mixer, private pool, Merkle tree management, and verifier contracts.

• Frontend:
  Next.js — user interface for zk-KYC, wallet creation, deposits, and private DeFi actions.

• Relayer & Merkle Tree Manager:
  Node.js — relayer service for submitting ZK proofs, managing off-chain Merkle trees, and coordinating cross-chain execution.

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📍 Deployed Addresses

🏦 Core Contracts (Mantle mainnet)

Contract	Address
Pool (entrypoint)	0x37741c6A9C54C0f8A8D659AB2386CFB5b3d318e8
Hasher	0x6ddf046B531839DfED9ec3bbEe919fFd9B401e1a
IdentityVerifier	0x203b923859Ed92d917e31D12EF56076CF70838e2
IDMixer	0xA9fE25E95D5F47FC6028d6760b64e4811DB3c4a9
DepositVerifier	0x1103Cf14ac34BD5D38a0D57D03Be2E7b597E0531
WithdrawVerifier	0xb7F3A2124DDE9b7Bc7eFfE7DC48bABC78c131976

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🌉 Cross-Chain Execution (Base mainnet)

Contract	Address
CrossMessenger	0x08f480f8b8075F0775F131006d0E9db92e85F585

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Note: Pool is the primary on-ramp into the private liquidity layer and should be referenced as the core entry point.

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📽️ Links

🖼️ Pitch Deck

🎥 Pitch Video

💻 Live Demo

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✅ Conclusion

UniCloak introduces a new primitive for privacy-preserving DeFi by combining zk-identity, private wallet commitments, and relayer-based execution over a unified liquidity pool. Unlike traditional mixers that stop at withdrawal and fragment liquidity across chains, UniCloak enables compliant private operations such as swaps, bridging, and cross-chain swaps without exposing user identity or fund origin. By anchoring liquidity on a single chain and accessing external liquidity through integrations, UniCloak delivers privacy, composability, compliance-awareness, and cross-chain reach — all without compromising user control or cryptographic integrity.