Deterministic Position Lifecycle State Machines (`FLAT → PENDING → OPEN`)

Eliminating race conditions and double-orders by modeling strategy execution as a strict finite state machine. Within the Quant & Broker APIs curriculum (Strategy DSL & Scripting → State Machines & Stops), this topic establishes the concrete quantitative rules and execution mechanics required for live market deployment.

Professional desks never rely on ambiguous visual guesses for state machine. Instead, every entry, invalidation level, and risk parameter is defined mathematically before a single order reaches the exchange gateway.

Hover over key terms below for instant definitions: State Machine, Position Lifecycle, and Race Condition. For the complete mathematical derivation and edge-case analysis, open worked example & quantitative lookup matrix for position lifecycle states.

• State Machine — Core structural driver governing deterministic position lifecycle state machines (`flat → pending → open`).
• Position Lifecycle — Prevents premature entries and enforces mechanical discipline across State Machines & Stops.
• Race Condition — Ensures worst-case scenario losses stay strictly within predetermined R-multiple budgets.

1. 1
   1. Pre-Session Calibration & Regime Check

   Measure baseline volatility and liquidity parameters for state machine prior to market open.
2. 2
   2. Mechanical Signal Confirmation

   Wait for a completed bar close confirming the position lifecycle threshold—never pre-empt mid-candle.
3. 3
   3. Risk-Normalized Sizing & Order Placement

   Compute exact lot quantity from the invalidation distance and dispatch via a Marketable Limit order.
4. 4
   4. Post-Trade Telemetry & Audit

   Log arrival price, fill slippage, and MAE/MFE metrics against the State Machines & Stops benchmark.

Implementation & Quantitative Model

1export type PosState = "FLAT" | "PENDING_ENTRY" | "OPEN_LONG" | "PENDING_EXIT" | "ERROR_HALT";2export function canSendEntry(state: PosState): boolean {3  return state === "FLAT";4}

Cross-reference standard risk definitions such as drawdown, slippage, and Sharpe ratio when auditing your logs.