IPnLTracker

IPnLTracker defines a minimal interface for tracking realized and unrealized profit and loss (PnL) based on filled orders.

class IPnLTracker : public ISubsystem {
public:
  virtual ~IPnLTracker() = default;
  virtual void onOrderFilled(const Order& order) = 0;
};

Purpose

• Record and update PnL metrics in response to order fill events.

Responsibilities

Method	Description
onOrderFilled	Called when an order is fully filled; updates PnL.

Notes

• Invoked only on complete fills — partial fills should be handled at a higher level if needed.
• Used in both real-time and simulation modes to compute performance metrics.
• Inherits from ISubsystem for coordinated lifecycle management.