Trading & fees

Everything below is how the engine actually prices and charges. Where a number appears, it is rendered from the constant the engine runs on — see where these numbers come from.

There is no order book

HardBasis does not match traders against each other and does not discover a price. Every fill executes against the HardBasis vault at a price derived from an external oracle. What you would call "the book" on another venue is, here, three published terms:

execution price = oracle mid
                ± spread        always against you
                ± skew impact   against you if your trade worsens
                                the imbalance, for you if it reduces it

You are never filled at a price better than the oracle mid plus the spread. That is a hard rule in the engine, not a policy applied case by case.

Orders execute on the next oracle update

An order never fills on the tick it was submitted on. The engine takes your request and executes it against the next oracle update — typically a few hundred milliseconds later.

That costs you a little immediacy and buys the venue its main defence against latency arbitrage. Because the vault is the counterparty to every trade, someone acting on a price the vault had not seen yet would be taking sats straight out of the pool backing everyone's positions. Same-tick execution is not offered, to anyone.

Limit, stop, and take-profit orders rest in the engine and trigger when the oracle touches your level — they then fill at the formula above, not at your trigger price.

The taker fee

Taker fee	3 bps of traded notional
Maker fee	none — there is no resting liquidity to provide
Charged in	sats, at fill time, rounded up

The fee is charged on notional, not on margin, so it does not scale with your leverage. It is the only explicit fee on a trade: the spread and the skew term are in the price, and funding is a payment between traders rather than to the venue.

The spread

The spread starts at a floor of 3 bps and widens on its own with short-horizon realised volatility and with the oracle's own confidence interval. It is not a lever an operator pulls per trade; it is a function of market conditions, and it widens fastest exactly when quoting a firm price would be most dangerous.

Skew impact

The vault holds the other side of every position, so a market where everyone is long leaves the vault short. Trades are priced against that imbalance: a trade pushing the imbalance further pays an impact term, and a trade reducing it earns one back. Rebates are bounded, so the two directions cannot be cycled against each other for a profit.

Funding

Funding is paid hourly and accrues continuously in between — you pay for the time you actually held the position, not for being open at the instant of a snapshot.

Settlement	every 1 hour
Rate	open-interest skew plus a baseline of 0.00125% per hour
Bounds	clamped to roughly ±75% per year
Direction	positive rate, longs pay shorts; negative rate, shorts pay longs
Settles in	sats, directly between position holders

The live rate is a market figure, not a policy figure, so this site does not print one. The app shows the current rate and the next settlement, and marks both visibly stale if its connection to the engine drops.

Margin, leverage, and liquidation

Maximum leverage	10×
Initial margin	10% of notional
Maintenance margin	1% of notional

If your equity falls below maintenance margin, the position is liquidated against the vault. A liquidation is not fee revenue you or a referrer earn on — see what the reward is calculated from.

Inverse contracts are convex: a long loses at an accelerating rate as the price falls. The engine uses the exact formula everywhere, never a linear approximation, and the liquidation price the app previews already folds in the spread you would actually close at.

Contracts

Inverse (BTC/USD). One contract is one dollar of notional. Margin and PnL are in sats. This is the flagship market.

Quanto (everything else). The underlying is priced in dollars and each contract pays a fixed number of sats per dollar the index moves. Because both you and the vault carry embedded bitcoin exposure in that payoff, quanto markets run wider spreads, lower position caps, and a funding adjustment of their own.

Prices are served on a fixed decimal grid — currently cents — so the price in a chart, in a fill, and in a liquidation is one number rather than three roundings of it.

Deposits and withdrawals

Deposits arrive over Lightning or Spark and credit your free balance. Withdrawal quotes show the network cost before you confirm.

Withdrawing your free balance works in every mode the engine can be in. If markets are halted, if the oracle is stale, if trading is paused for any reason at all — free balance still leaves. That is a covenant in the engine's design, enforced by tests that fail the build if a withdrawal path ever gains a dependency on a risk, compliance, or referral control.