How it works

This page shows three things: how a market runs from listing to settlement, where your money is, and how a trading system connects. Each part has a diagram and links to the page that has the detail.

Inflection runs on a testnet. The money in this page is test USDC on Base Sepolia. It has no real value.

How a market runs

A market is one window on one asset, such as Bitcoin from 14:50 to 14:55 UTC. It moves through four states.

1. Open. The exchange lists a window before it starts. The market takes orders. It has no strike yet.
2. Live. When the window starts, the exchange records the asset’s price as the strike. The market still takes orders.
3. Closed. Trading stops at the end of the window. The exchange cancels your resting orders. Your positions stay open.
4. Settled. The outcome is recorded and positions are paid.

Up wins if the price at the end is at or above the strike. Otherwise Down wins. A market usually settles within a few minutes after its window ends. Each winning lot pays 10,000 units, so a winning share pays $1.00.

If a price is missing, the market is void. Each lot then pays 5,000 units, on either side. See Settlement.

For the fields, the statuses and the fee formula, see Markets. For the price sources and the void rules, see How a market resolves.

Where your money is

Your money is USDC in a vault, a smart contract on Base. The vault keeps the cash and the positions of every account. The exchange matches orders. It does not hold the money.

Deposits and fills

You deposit from the wallet that is linked to your account. The vault pays out only to that wallet. You can’t change the linked wallet later.

The exchange keeps a fast copy of every balance in its ledger. Before an order reaches the market, the exchange checks it against your balance. The vault is the record. If the exchange’s copy differs, the vault is right. The exchange takes back a fill that the vault skips, and uses the fee that the vault charged. A person at the exchange reviews any other difference before the copy changes.

The exchange posts fills to the vault in small batches. A fill usually reaches the vault within seconds of the trade. The vault applies a fill only after these checks, among others:

• A session key signed each order, your wallet approved the key, and the key had not expired.
• The fill price is within the limit that each order signed. A market order can sign no limit.
• The fee is within the most that each order accepts.
• No account’s cash goes below zero.

The vault skips a fill that fails a check. Fills of other orders in the batch still apply. The exchange then takes the skipped fill back from both accounts.

Settlement

Only markets with trades go to the vault. When a market with trades ends, the vault resolves it from two prices: the start and the end. On testnet, our own key posts them. The vault applies one rule: Up wins if the end price is at or above the start price. See Who decides on testnet.

For a market with trades, the exchange waits for the vault’s outcome and settles with it. The exchange settles a market with no trades itself, from the same prices. A winning lot pays 10,000 units into the cash of its account.

If a price is missing, the market is void. For a market with trades, the vault sets this. It lets anyone do it 24 hours after the window ends, and the vault’s admin can do it sooner. For a market with no trades, the exchange settles it as void. Each lot then pays 5,000 units, on either side.

Taking money out

Withdrawals through the app are coming. Until then, and at any time the exchange or the site is down, you can use the timed exit.

The timed exit takes two transactions from your linked wallet. The first asks the vault for an amount. The second pays that amount, or all your cash if you have less by then, after a wait that the vault enforces. The wait is one hour on testnet. From 60 seconds after your request, the vault skips a fill that would take your cash below that amount. The exit does not need the exchange. A pause by the vault’s admin does not stop it.

With the site down, you need your wallet’s key. If you signed up with an email, export the key first. See Take your money out without us.

The vault pays cash only. A position in a market that has not paid out is not cash yet. The same guide shows how to turn a position into cash.

How a trading system connects

A trading system uses three keys. Each has one job.

Key	What it does	Who holds it
Wallet key	Owns the account’s money. Approves each session key.	You, or your wallet provider.
API key	Signs your HTTP requests and the trading socket handshake.	Your trading system.
Session key	Signs each place, modify and cancel.	Your trading system.

To connect:

1. Make an API key. API keys are not open to outside developers on testnet yet.
2. Make a session key on your side. It is a P-256 key pair. The private key stays with you.
3. Register the session key with your API key. If your account has a linked wallet, the wallet signs a grant for the key first.
4. Open the trading socket. Sign each place, modify and cancel with the session key.

The signing guide has the steps and code.

The gateway checks the signature of each order before it checks your collateral. Later the vault checks each fill: the signature of both orders and the approval of each key by its wallet.

A session key stops working when its lifetime ends. With an API key and a grant, the lifetime is at most 180 days. The wallet signs the grant, not the orders.

Do not share a session key. Anyone who has one can trade your account at any price. The exchange adds no price limit of its own to a signed order. A session key can’t send your money anywhere: the vault pays only your linked wallet. To place your first order, see Your first order.