Trade Stocks Without Showing Your Hand

Orders go in sealed, open together, and cross at the Uniswap midpoint in one batch on Robinhood Chain. Nobody sees your size before the batch stops taking orders.

The Blacksite app

Nine stocks, priced by their Uniswap pools.

  • NVIDIA
  • Apple
  • Tesla
  • Meta
  • Alphabet
  • Microsoft
  • Amazon
  • SpaceX
  • SPYS&P 500

A Dark Pool for Tokenised Stocks

On a public pool, every order is a signal. Blacksite keeps yours sealed, then fills it against the other side at the price the pool already shows.

Your orderSealed
Market
Side
Size
Limit
On-chain right now0x9c4e7d21…a1f0 · bond 1.00 USDG

Sealed Until the Batch Closes

Your order goes on-chain as a hash and a fixed 1 USDG bond. Market, side, size and limit stay in your browser until the reveal window opens.

Midpoint · NVDALive
$—
Uniswap V4 poolL1 —
Buyersheavier side6 / 10pro rata
Sellerslighter side6 / 6in full
Sizes: illustrationOne price for every fill

One Midpoint for Every Order

Every crossed order in a batch fills at the same price: the midpoint of the stock's Uniswap V4 pool, read in the settlement block. Size has no price impact.

Price guardPer market
SPY0.60 %
NVDA, AAPL, META…1.00 %
TSLA1.50 %
SPCX2.00 %
At settlementMidpoint too far from the batch average: the batch is voided and every order comes back.

No Fill at a Moved Price

The midpoint is sampled all batch long. If it jumps away from that average at settlement, nothing trades at the moved price and every order is returned.

Batch ——
Commit16 blocks · 3 min
Reveal5 blocks · 57 s
Settlewithin 26 blocks
Next phase—

A Batch Every Four Minutes

Sixteen L1 blocks to commit, five to reveal, then anyone can settle. A batch left unsettled for 26 blocks is voided, never filled at a stale price.

Hidden Until the Reveal

While a batch takes orders, the chain only holds a hash and a bond. Nothing a watcher can trade ahead of.

Which Stock

The market id is inside the hash. Nobody can tell whether you are about to trade NVIDIA, Tesla or the S&P 500.

Buy or Sell

Buyers and sellers post the same 1 USDG bond from the same balance, so a commitment looks identical from either side.

Size

Nothing is locked from your vault until you reveal, so a commitment says nothing about how much you hold or want.

Limit Price

Your worst acceptable price is sealed with a 32-byte salt only you hold, so nobody can guess it by hashing round numbers.

Commit. Reveal. Cross at the Midpoint.

Batches run back to back on the Ethereum block clock that Robinhood Chain exposes, one block every 11.4 seconds.

Deposit

Put USDG or a listed stock into the vault. Deposits and withdrawals are plain transfers with no fee beyond gas.

Commit

Post the hash of your order and a random salt, with a 1 USDG bond. The order itself never leaves your browser.

Reveal

Open the order in the 5-block reveal window. The contract checks it against the hash, locks the size and returns the bond.

Settle

Once reveals close, anyone can settle. Every crossed order fills at the pool midpoint read in that block.

Split Fairly

The lighter side fills in full, the heavier side pro rata. Every division rounds toward the venue, so it never pays out more than it took in.

Withdraw

What does not cross goes back to your vault in the same call. Free balance can be withdrawn at any time, in any phase.

VaultFree balance
USDG6 decimalsdeposit · withdraw
Listed stocks18 decimalsdeposit · withdraw
Anything elserejected
FeeGas only
commit(Sealed
0x9c4e7d21b0f65a3e8c12d4f07b9a6e3c
5d80f2a91c47e6b3d05f8a29c1e7a1f0
Bond1.00 USDG
Saltkept in this browser
)Up to 8 per batch
Reveal · 5 blocksChecks
Preimage matches the hashok
Market listed and enabledok
Free balance covers the sizeok
Book under 96 ordersok
Bondreturned
settle(batch, market)Anyone
Book emptyvoid
Fewer than 2 price samplesvoid
Outside the price guardvoid
Otherwisecross
A void chargesNo fee
MatchingOne price
buys = Σ usable USDG, mid ≤ limit
sells = Σ shares × mid, mid ≥ limit
matched = min(buys, sells)
fill(o) = o.size × matched / side
RoundingToward the venue
After settlementYour vault
Crossedat the midpointfilled
Not crossedsame callreturned
Free balanceany phasewithdraw
Owner can freeze itNever

Everything on One Screen

Pick a stock, set a size and a limit, seal the order. The app keeps your salt in the browser and brings you back for the reveal.

The Blacksite app

Enforced by the Contract

Not promises. Rules written into code that nobody, including us, can change.

Your Limit Holds

A buy never fills above its limit, a sell never below. Whatever does not cross comes back.

No Stale Fills

A batch not settled within 26 blocks is voided and every order is returned in full.

Always Withdrawable

No phase, pause or owner action can stop you withdrawing a free balance.

Solvent by Design

Settlement asserts it never pays out more than it took in. The dust goes to the treasury.

Fees & Staking

One matching fee, capped in the bytecode. Most of it goes to people who stake $BLACKSITE.

Matching Fee

Charged only on the part of your order that actually crosses.

0.10%/
side

In USDG, on the value that crossed

  • Ceiling of 0.50 %, fixed in the bytecode
  • Any change waits 48 hours
  • Each order keeps the fee in force at reveal
  • Unfilled size pays nothing
  • A voided batch charges nothing
  • Deposits and withdrawals: gas only
Seal an Order
Commit Bond

A fixed deposit per order, the same for buyers and sellers.

1.00/
USDG

Returned the moment you reveal

  • Taken from free USDG, buy or sell
  • Forfeited only if you never reveal
  • Up to 8 commitments per batch
  • Up to 96 orders per market per batch
  • Forfeits are split like fees
  • The salt never leaves your browser
Read the Docs

Before You Trade

The short answers. The docs have the long ones, including everything that is not guaranteed.

No. There is no liquidity curve and no LP. Your order only fills against the other side of the same batch. If nobody is there, nothing fills and your size comes back.

From each stock's canonical Uniswap V4 pool against USDG. Blacksite never trades on it: it only reads the midpoint, the same slot0 a swap would move.

While the batch takes orders, only a hash and a 1 USDG bond. Once you reveal, your order is public for about a minute until settlement. Vault deposits and withdrawals are ordinary transfers.

You cannot reveal, and the 1 USDG bond is forfeited at the end of the batch. The app keeps the salt in your browser and lets you save it as a file.

Not yet. It is tested, including fuzzing of settlement, and its source is verified on Sourcify. Deposit only what you are prepared to lose.

Still Have a Question?
Read the Docs