Going live

Work in this order. It is the one that fails cheapest, because everything it surfaces costs a test run rather than a customer's money.

• Build the whole flow against the sandbox: quote, reserve, order, position, exit, settlement.
• Trigger every failure mode on the Errors page deliberately and handle each one, including killing your own process mid-order and recovering it by clientOrderId.
• Run a settlement consumer through a full cycle, void included, and prove it is safe to run twice.
• Reconcile a period and prove it balances.
• Agree the commercial terms below.
• Swap the key.

Every one of these is reachable in the sandbox. Run them there.

Pricing and display

• Render the quote's executionPrice on every ticket. No surface anywhere renders a reference probability as a price.
• Where no executable price is published, show no price and disable the controls. Never fall back to the reference.
• Read priceBasis. Display a reference-basis quote as an estimate, or not at all.
• Carry prices at the precision you received them. No rounding to whole cents anywhere in the path from response to display.

Money

• Act on operatorMoney and operatorExitMoney, never on the float fields beside them. Parse amounts as decimal strings and never through a float.
• Assert both identities before posting: authorizationAmount = actualDebit + releaseAmount and actualDebit = tradeAmount + platformFee + venueFee. Exactly, not to a tolerance.
• Release the non-zero releaseAmount a partial fill returns. Debiting the full stake keeps money that is not yours to keep.
• Credit sellProceeds on a sell and never debit. A null operatorMoney is not a reason to fall back to the entry shape.
• Reserve the stake on your wallet before the quote, not after the order.

Orders and recovery

• Derive every clientOrderId from the reservation in your own ledger, and reuse it on every retry.
• Hold the authorization on 409 reconciliation_required and poll. No branch anywhere releases on it, and no branch re-quotes on it.
• Exercise the recovery path: kill the process mid-order, find the order again with GET /api/v1/orders?externalUserId=&clientOrderId=, then read that orderId back with GET /api/v1/orders/{id}.
• Switch your wallet on settlementState, not on status, and prove you are reading it from the single-order route. The list route does not carry it, and a branch comparing undefined to "pending" releases a hold it must keep.
• Re-quote and re-confirm with the player on a 409. Never retry a 422 unchanged.
• Handle partially_filled. filledQuantity, not the quote's contracts, is what the player holds.

Settlement and operations

• Key the settlement consumer on the settlement id or positionId, advance its cursor only after a successful credit, and make it safe to run twice.
• Credit a void from voidCredit, fee included, and run a full settlement cycle including a void end to end.
• Read GET /api/v1/reconciliation on a nightly close and alert on any critical finding.
• Read simulated and surface it somewhere your operations team can see it.
• Back off with jitter on 429 and 5xx, and read RateLimit-Remaining wherever it arrives. Two things it will not tell you: the quote and order routes answer without the headers, and a second per-tenant ceiling counts every key you hold together and is not reported on any header. Keep a retry path rather than a purely predictive one.
• Store keys in a secret manager and rehearse the rotation path.
• Narrow scopes per credential. A read-only integration key does not carry orders:write.

Part of a launch is a conversation rather than a contract shape. Settle these per deployment, before the key changes: the custody structure, including per-user versus omnibus accounts; the regulatory perimeter you operate inside; how KYC and AML responsibility divides between you and Parity; and the commercial terms.

• Sandbox keys are minted pk_test_ and live keys sk_live_. Mode is a property of the operator record, so no header or parameter moves a caller across the boundary.
• The balance, ledger, funding and sandbox test-control routes answer 403 sandbox_only for a live tenant. They model a Parity-held balance, which is the wrong model for a live operator: your own wallet is the authority on what a player may stake.
• Every other route behaves identically in both modes, against the same tables and the same code. What differs is what happens after an order is cleared to execute: see below.
• simulated is on every quote, order and settlement payload, and tells you whether a fill was produced locally.

The mechanics of each of those live on Environments.