Documentation

Overview

DarkpoolFi is a private execution venue for stock tokens on Robinhood Chain. Funds sit in a shielded pool as private notes, orders are sealed so their side, size and limit are not public, and every eligible order in a 5-minute window crosses at one shared Chainlink reference price.

• No public order book. Other traders never see your orders; the market only sees that an order joined a window.
• Proofs are made in your browser. Zero-knowledge proofs show a spend or order is valid without revealing which notes it uses.
• One price per window. Nobody gains by being first; everyone in the window gets the same reference.
• Self-custody. Only your wallet can derive the keys that spend your notes.

Getting started

Requirements

• MetaMask. DarkpoolFi works with MetaMask only. If another extension such as Phantom also injects a wallet, the dashboard still selects MetaMask.
• Robinhood Chain (chain ID 4663, gas in ETH). The dashboard asks MetaMask to switch or add the network when needed.
• ETH for gas. Keep about 0.001 ETH spare in your wallet: proof transactions reserve their full gas up front and refund what they don't use.

First steps

1. Open the dashboard and go to the Shielded pool tab.
2. Click Unlock shielded account and sign the message in MetaMask. Signing is free and sends no transaction; it derives your private pool keys in the page.
3. Deposit ETH. The deposit becomes Spendable once it joins the pool tree, usually within a couple of minutes.
4. Seal an order from the Trading desk or the Shielded pool tab.

Your keys

Your keys exist only in memory while the page is open and are never sent to a server. Reloading the page locks the account; sign again to unlock. Because the keys come from your wallet's signature, the same wallet recovers the full account on any device: balances, orders and history are rebuilt from the pool's public events.

The dashboard

Trading desk

Markets with their live Chainlink reference prices, the countdown to the current window's close, and an order ticket. The ticket seals a standard shielded order from your unlocked account; your open orders and recent results appear below it. Other order types are in the Shielded pool tab.

Private balance

Your shielded account at a glance: available ETH (spendable plus arriving), ETH committed to open orders, token holdings valued at reference prices, and funding history. Deposit and Withdraw open the matching Shielded pool forms.

Activity

Your activity lists deposits, withdrawals, note changes, sealed orders and fills, tagged Shielded pool, and can be exported as CSV. The Crossing windows and Delayed public tape views currently cover the previous private balance system.

Shielded pool

The full toolkit: account status and balances (Spendable, Arriving, In orders, Notes), deposit, withdraw, sealed orders of every type, merge and split, backstop liquidity, and selective disclosure. A status card shows each step while an action runs.

Notes and the pool tree

Your balance is a set of notes: private commitments to an owner, an asset, an amount and the deposit they descend from. Spending a note publishes a one-time nullifier, so a note can never be spent twice, without revealing which note it was.

Balance states

Tree batches

New notes are queued on chain and appended to the pool's Merkle tree in batches of up to 16. A note becomes spendable once its batch lands, typically within a couple of minutes. The tree holds just over one million notes.

The same-deposit rule

Every deposit carries a private label that follows its funds through every later note. Only notes from the same deposit can be combined in one transaction. A withdrawal can draw on at most two notes from one deposit; if your balance is spread over several deposits, withdraw in parts.

Merge and split

• Merge joins your two largest spendable notes from the same deposit into one.
• Split carves an exact amount out of a single note. The note must cover the amount plus the relayer fee. The usual reason to split is to create a small, separate ETH note for paying relayed order fees.

Deposits and withdrawals

Deposits

Deposit ETH or a listed stock token from your wallet. Tokens ask for an approval of the exact amount first. Each deposit also carries a small ETH deposit fee that pays for adding it to the pool tree; the form shows the current amount.

Withdrawals

Withdraw any amount to any Robinhood Chain address. Whatever is left in the notes you spend returns to you as a new change note.

Token withdrawals are always sent from your wallet. The relayer fee tracks network gas: around 0.0004 ETH at normal gas, higher during spikes. The form always shows the live fee.

Association set

The pool supports an association set: a published list of screened deposits. When it is enforced, a withdrawal proves in zero knowledge that its funds come from an approved deposit, without saying which one. Deposits from blocked addresses are refused at the door.

Sealed orders

Crossing windows

Orders collect in 5-minute windows, numbered by time. An order joins whichever window is open when its transaction lands. After the window closes, the reference price is sealed from Chainlink and the window is settled.

1. Seal. Your order is proved and encrypted in the browser, then submitted through the relayer (or your wallet).
2. Collect. It rests in the window. Its side, size and limit are not public.
3. Cross. After the window closes, eligible orders cross at one reference price. Leftover interest can fill against the backstop vault.
4. Settle. Fills, refunds and released locks return to you as private notes, typically within about 10 minutes of placing the order.

Placing an order

• Size in tokens: at least 0.001, up to 6 decimals.
• Price limit (optional), in USD per token. A buy is eligible when the reference is at or below the limit; a sell when it is at or above.
• Buys lock ETH from a single note. The suggested amount is size × reference ÷ ETH price plus 2.05% for the fee and headroom; unused ETH is returned. Sells lock tokens from a single token note.
• Relayed orders pay their relayer fee from a separate ETH note, so the fee reveals nothing about the order. Split a note first if you need one.

If it doesn't fill

Live windows

A window is live when both price feeds are fresh, the token's oracle is active, and the time falls in the trading session (Sunday 20:00 to Friday 20:00, New York time). Nothing fills in a window that is not live: orders set to keep roll forward, and released orders get their lock back.

Reclaiming a lock

If a window is not settled within one hour of closing, its orders show Window was not settled · reclaim your lock. Reclaiming closes the window if needed and returns your lock as a note. Both steps are sent from your wallet.

Order types

The Trading desk ticket places standard orders. Every type below is available in the Shielded pool tab's Sealed order form.

Backstop liquidity

The backstop vault gives each market depth when a window's own interest is one-sided. Liquidity providers add ETH and/or one stock token to a market's book. After the uniform cross, leftover buy interest fills at reference + spread and leftover sell interest at reference − spread, pro rata, with the normal venue fee.

• Spread: 50 bps per book (maximum 200 bps).
• Next-window offer: the tokens the vault can sell and the ETH it can spend next window, capped per window. A book holding only ETH can only buy from sellers, and vice versa.
• Adding liquidity mints shares at Chainlink value; withdrawing burns shares for the same fraction of the book's ETH and tokens. Both go straight from your wallet. The dashboard does not show your share balance yet, so keep a record of the shares you add.
• Rebalancing: the vault can swap toward an even ETH/token split on Uniswap v3 within a slippage bound. Only the vault trades on the AMM, never user orders.

Privacy model

What is public and what stays private

Proofs in the browser

Deposits, transactions, orders and reclaims are proved on your device with Noir circuits and the Barretenberg UltraHonk backend, using Poseidon2 hashing; on-chain verifiers check every proof. The Merkle path to your notes is also built locally, so no server learns which note you are spending. Window crossings and tree batches are proved by the operator and verified on chain in the same way.

Who can read what

• The public and other traders never see order details, only the data listed above.
• The settlement operator decrypts sealed orders to compute each window's cross. It sees the order's terms and the deposit its funds came from, but it cannot spend your notes or change the outcome: settlement must pass an on-chain proof.
• You decrypt your own notes, orders and results with your viewing key, derived from your wallet signature.

Messages are encrypted with ECIES (secp256k1 key exchange with AES-256-GCM). Your spending key never leaves your device.

Selective disclosure

For audits or compliance, you can seal your viewing keys to an auditor's public key and publish the grant on chain. The auditor can then rebuild every note, order and result of the account, past and future, but can never spend.

Fees

Limits

Troubleshooting

Proofs take time on slower devices. The status card shows each step with a timer, so click once and let it finish.

Previous private balance

Before the shielded pool, DarkpoolFi ran an account-based private balance. It no longer takes deposits or new orders. Wallets that still hold funds there see a Previous private balance · Withdraw only panel in the Private balance tab. Nothing is moved automatically: withdraw to your wallet, then deposit into the shielded pool.

Contracts

DarkpoolFi runs on Robinhood Chain (chain ID 4663). Verify any address on the block explorer.

Questions? Reach us on X or Telegram. Read the Risk Disclosure before trading.