Execution Flow

Execution is modeled explicitly so backtests reflect realistic cost and fill behavior.

Execution Diagram

```mermaid sequenceDiagram participant Strategy participant Engine participant Execution participant Portfolio

Strategy->>Engine: submit_order Engine->>Execution: apply slippage/commission/impact Execution->>Engine: fill Engine->>Portfolio: update positions + cash ```

Steps

1. Strategy submits an order via StrategyContext.
2. The execution pipeline applies slippage, commission, impact, and latency.
3. Fills update the portfolio and metrics.

Execution Configuration

Execution is configured under execution.* and implemented by ExecutionFactory:

• Slippage models: zero, fixed_bps, regime_bps.
• Commission models: zero, fixed.
• Transaction cost models: zero, fixed_bps, per_share, per_order, tiered.
• Market impact models: zero, fixed_bps, order_book.
• Latency model: latency.ms.

See guide/execution-models.md for full config details.