Every balance, every transfer, every counterparty you have ever touched on a public chain is visible to anyone, forever. For payroll, treasury management, and personal savings, that transparency is a defect, not a feature.

Nullifier is privacy infrastructure for on-chain finance: a zero-knowledge privacy pool, live on Robinhood Chain mainnet. Deposit $ETH and $USDG into one shared shielded pool, transfer privately between registered accounts, and withdraw to any address, with no on-chain link between your deposit, your balances, and your withdrawals.

The protocol is non-custodial by construction. No admin key can move user funds. Every spend requires two independent factors: a shielded key hierarchy derived on your device, and a fresh EIP-712 signature from your own wallet, verified inside the circuit. All proving happens in your browser. Nothing secret ever leaves your device.

We publish limits as plainly as features: a young anonymity set, beta governance keys, no external audit yet. Everything we claim is labeled, measured, and verifiable on-chain.

Privacy, crystallized. On Robinhood Chain.

Start here:
nullifier.pro

On a public EVM chain, your financial life is an open database. Every transfer, every balance, every counterparty relationship is permanently visible to employers, competitors, and anyone with a block explorer.

This breaks legitimate activity. A company cannot run payroll on-chain without publishing every salary. A treasury cannot rebalance without signaling its strategy. An individual cannot save without broadcasting their net worth. And once coins carry a publicly inspectable history, individual units become discriminable by that history. Privacy is a prerequisite for fungibility.

Existing answers each gave up something essential. Fixed-denomination mixers force rigid amounts, leak timing correlations, and historically offered weak guarantees against operator abuse. Account-based systems often weaken the anonymity model or rely on trusted hardware. Fully transparent compliance coins satisfy regulators but fail privacy entirely.

Nullifier's position: a note-based shielded pool with arbitrary amounts, one multi-asset pool holding $ETH and $USDG, client-side proving, screening at the edges only, and a private interior with no operator mediation. Users always keep the ability to exit without anyone's cooperation.

Read how the problem shapes the design:
nullifier.pro/app/docs

Nullifier is six layers deep, and the layering itself is a privacy mechanism: each layer sees strictly less than the one above it.

Layer 1, Application. The app at nullifier.pro is a React SPA with connect-only wallet flow: no login, no user records, no protocol secrets. Layer 2, Client SDK. Two Web Workers hold your keys, scan your notes, and build UltraHonk proofs. Secret-bearing memory never touches the DOM main thread.

Layer 3, Services. A public relayer submits shielded transactions so you never pay gas from a linked address. A private guard screens and settles deposits. A private indexer republishes chain data. They are deliberately independent: an indexer bug cannot stall deposits. Layer 4, Data. Authenticated chain views that your client verifies against on-chain accumulators on every sync. A lying indexer degrades availability, never integrity.

Layer 5, Settlement. The UUPS pool contract, five generated verifier contracts, depth-20 Merkle trees, and nullifier accumulators, all verified on mainnet. Layer 6, Platform. Robinhood Chain, an Arbitrum Orbit L2 with roughly 100 ms block times, settling to Ethereum. Built on the @arbitrum Orbit stack.

The attached diagram maps the full flow from your browser to settlement.

Read the architecture:
nullifier.pro/app/docs

Three shielded operations. One pool. Here is the full lifecycle of private value on Nullifier.

1. Shield. Connect an ordinary browser wallet, sign one onboarding message, deposit $ETH or $USDG. The deposit enters a pending state while an independent guard screens it against sanctions data. Once approved, it becomes a note inside the pool's Merkle tree. First-time registration bundles free with your first deposit.

2. Send. Transfer any amount to any registered account. The transfer reveals neither sender, recipient, nor amount. Your browser builds an UltraHonk zero-knowledge proof in about 5 seconds on desktop, and a relayer submits it, so you never pay gas from a linked address. Transfers carry zero protocol fee.

3. Withdraw. Exit to any address, any time, through the relayer or fully self-submitted. If withdrawals are ever paused, the pause auto-expires within 72 hours per incident. A pending deposit can always be pulled back through an escape hatch that governance cannot pause.

No custody. No surveillance of the shielded interior. No dependence on operator goodwill.

Try the app:
nullifier.pro/app

The Nullifier Protocol Whitepaper v1.0 is out now: 40 pages specifying the zero-knowledge privacy pool that has been live on Robinhood Chain mainnet.

Read the paper:
nullifier.pro/Nullifier_Offi…

Not a vision document. A specification of the deployed system, down to its hashes, circuits, contracts, services, and their measured costs.

Inside: the full cryptographic architecture (Poseidon2 with 22 domain-separated tags, Grumpkin note encryption, depth-20 LeanIMT Merkle trees, EIP-712 spend authorization verified in-circuit), the five Noir circuits proved with UltraHonk, the privacy model with its leaks stated explicitly, the security architecture and threat matrix, measured performance figures, and the governance system as deployed. Every number is measured, not aspirational: 4.4 to 4.9 second proving on desktop, 9,152-byte spend proofs, 675 green tests, and a real-funds end-to-end verification on mainnet.

It also states what we do not claim. A small anonymity set at launch. Verified facts and design intent carry different labels throughout, so you always know which is which.

This document is a technical specification, not investment material. Trust only links from this account and nullifier.pro.

Most wallets protect funds with one key. Nullifier requires two independent factors for every shielded spend, and one of them never leaves your device.

Factor one: a shielded key hierarchy (nullifier key plus viewing keys) derived from a single EIP-191 onboarding signature, computed inside a dedicated Web Worker. No server ever receives the signature, the derived keys, or your note plaintexts. A leaked onboarding signature compromises privacy only. It cannot move funds.

Factor two: a fresh secp256k1 signature from your own wallet over an EIP-712 typed struct that binds the exact action: asset, amount, recipient, fee, relayer, deadline. The circuit verifies this signature inside the proof itself. A phished spend signature costs exactly that one signed action, then expires.

Underneath it all: Poseidon2 hashing with 22 domain-separated tags, notes committed into depth-20 LeanIMT Merkle trees with epoch rollover, payments encrypted to Grumpkin curve keys, and five Noir circuits proved with UltraHonk, pinned to Barretenberg 5.2.0 with deterministic builds.

Two factors. One proof. Zero custody.

Read the cryptographic architecture:
nullifier.pro/app/docs

NULL is live.

The official Nullifier token has launched on @ponsdotfamily, the leading launchpad on Robinhood Chain (chainId 4663). Contract address:

CA: 0x42e99b08cf139abcae524e749cb93e747526130f

Trade page:
Token facts: fixed supply and 100% public allocation as stated in the whitepaper
nullifier.pro/Nullifier_Offi…

Product came first. The Nullifier protocol has been live on mainnet since October 7, 2026: a non-custodial zero-knowledge privacy pool for $ETH and $USDG, with real deposits screened and approved on-chain and a real withdrawal executed with a verified proof. The pool works fully without a token, and it still does. NULL starts as a community asset. Any future relationship with protocol fees, governance, or relayer incentives will be announced with verified contract addresses, not retrofitted promises.

web app: nullifier.pro
telegram: t.me/Nullifierpro
docs: nullifier.pro/app/docs

The official Nullifier app is fully live.

nullifier.pro is the reference client for the Nullifier protocol, running in production on Robinhood Chain mainnet (chainId 4663). Connect an ordinary browser wallet, sign one onboarding message, and you can shield $ETH and $USDG, send privately to any registered account, and withdraw to any address. All keys and all proving stay on your device. No login, no user records, no custody.

Every contract behind the app is verified on the official explorer. Deployed October 7, 2026, block 82,607,732:

Pool proxy (ERC-1967), the only contract you ever interact with:
robinhoodchain.blockscout.com/address/0x104C…

Core contracts:
Implementation (UUPS): robinhoodchain.blockscout.com/address/0x72a9…
TimelockController (48 h): robinhoodchain.blockscout.com/address/0xbDc1…
Treasury: robinhoodchain.blockscout.com/address/0x77db…

Verifier contracts (UltraHonk, Barretenberg 5.2.0):
Transfer2: robinhoodchain.blockscout.com/address/0x837f…
Transfer6: robinhoodchain.blockscout.com/address/0x8336…
Withdraw2: robinhoodchain.blockscout.com/address/0x1dB3…
Withdraw6: robinhoodchain.blockscout.com/address/0xF902…
ReceivingKey: robinhoodchain.blockscout.com/address/0xA00a…

Every verifier accepted its proof fixture and rejected a mutated copy on-chain at setup. Bookmark this post.

Security note: the only official app is nullifier.pro. Nullifier never DMs links or contract addresses. Trust only this account and the official explorer. If a contract is not listed here, it is not ours.

Open the app:
nullifier.pro/app

Privacy protocols rarely tell you exactly what they leak. We publish our leak list.

What Nullifier hides: the link between your deposit, your notes, your transfers, and your withdrawals. Internal transfers reveal neither sender, recipient, amount, nor balances. Note contents live under Poseidon2 commitments and Grumpkin encryption. Nullifiers are opaque values that cannot be tied back to any note or owner.

What stays public by design: deposits and withdrawal payouts, with addresses and amounts. Entry is observable because compliance happens at the edge. Privacy accrues to everything that happens after entry.

What we state honestly: relayed transfers leak one bit (the fee asset), the 2-input versus 6-input circuit class is visible, and the pool is young, so the anonymity set is small today. Amount and timing fingerprinting is practical at low volume, which is why the app recommends round amounts and a delay between deposit and withdrawal. Privacy here is asymptotic: it strengthens with every user who joins the set.

Note-based pools stand on the work of teams like @RAILGUN_Project, who proved the model in production. We carry it forward with measured limits, not marketing.

See the full privacy model:
nullifier.pro/app/privacy

Compliance and privacy are not opposites. The mistake is putting surveillance inside the pool.

Nullifier screens at the edges only. Deposits sit in a pending state until an independent guard service checks the depositor against TRM sanctions data, fail-closed: if the screening provider goes down, deposits route to human review, never to auto-approval. The guard's only on-chain powers are approve and reject. It cannot redirect or receive funds, and its worst-case abuse is a wrongful approval or a refund delay bounded at 1% of the deposit.

The shielded interior has no operator mediation. Transfers inside the pool touch no screening layer. At withdrawal, the relayer screens the recipient before submission, while the contract itself enforces no recipient policy, so self-submission always remains possible.

Compliant privacy was pioneered in production by teams like @0xbowio with association sets. Nullifier implements the same principle with a two-phase deposit gate and an unpauseable escape hatch.

Compliance by design:
nullifier.pro/compliance