FIX Order Entry
The FIX order-entry session accepts order placement, cancellation, and cancel-replace flows.
New order
Use NewOrderSingle (35=D) for standard orders.
| Field | FIX tag | Required | Notes |
|---|---|---|---|
| ClOrdID | 11 | Yes | Client order id and idempotency key |
| Symbol | 55 | Yes | Example: BTC-USDC |
| Side | 54 | Yes | 1 buy, 2 sell |
| OrdType | 40 | Yes | Limit, market, stop, or extension type |
| OrderQty | 38 | Yes | Base quantity |
| Price | 44 | Limit only | Tick-aligned decimal |
| TimeInForce | 59 | Optional | Day, IOC, FOK, GTC extension |
| DisplayQty | 1138 | Optional | Iceberg visible quantity |
Cancel
Use OrderCancelRequest (35=F) with the original ClOrdID and a new cancel
request id.
Cancel-replace
Use OrderCancelReplaceRequest (35=G) for atomic amend flows. If the replace is
rejected, the original order remains active unless the rejection explicitly
states otherwise.
Rejections
Application-level rejections return BusinessMessageReject or
OrderCancelReject. Pre-trade business rule failures map to the same error
concepts documented in Error Model.
Senticore extension areas
| Extension | Purpose |
|---|---|
| Post-only flag | Maker-only enforcement |
| Reduce-only flag | Position-reducing protection |
| Conditional strategy | Stop-loss, take-profit, OCO |
| Algo strategy | TWAP, VWAP, iceberg behavior beyond DisplayQty |