> For the complete documentation index, see [llms.txt](https://docs.nullmask.pro/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.nullmask.pro/nullmask.md).

# Nullmask

Privacy-preserving DeFi protocol powered by zero-knowledge proofs

Nullmask enables shielded deposits, transfers, withdrawals, and swaps on EVM chains. Users interact with a standard wallet — the protocol intercepts transactions, generates zero-knowledge proofs client-side, and submits them through a relayer to hide the sender's identity.

Funds are held in a UTXO-based privacy pool secured by Poseidon2 commitments and Merkle membership proofs.

### Key Features <a href="#key-features" id="key-features"></a>

* **Shielded Transfers** — Send tokens privately without revealing sender, recipient, or amount on-chain
* **Shielded Swaps** — Execute Uniswap V2 swaps without exposing user identity
* **Private Deposits & Withdrawals** — Move funds in and out of the shielded pool with ZK-verified proofs
* **Multi-Chain** — Deployed on Ethereum, Arbitrum, MegaETH, Base, and BSC
* **Standard Wallet UX** — No special wallet needed; works with MetaMask and any EIP-1559 compatible wallet
* **Hardware Wallet Support** — Full security without extracting spending authority from the device
* **ERC-20 Support** — Shield any supported ERC-20 token alongside native ETH
* **Built-in Compliance** — Deposit screening with retrospective taint recovery via revocation keys


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