Trade Execution Engine

Purpose

"How do we execute & manage trade to protect capital & maximize profit?"

This component is the executor. It takes signals from Layer 4 and:

Converts signals to trades with realistic slippage
Monitors open positions (stop, target, time)
Manages stops dynamically (breakeven, trailing)
Calculates complete P&L with all costs

Trading Market Principle

"Let winners run, cut losers short. Protect profits once we have them."

Breakeven stop = protect capital once trade is working → move stop to entry at 25pt profit
Trailing stop = let winners run → trail stop behind price using ATR
Time exit = don't hold losing trades forever → 8 hour maximum
Slippage modeling = realistic execution → winners don't fill perfectly either

Trade Lifecycle

        ┌───────────────────────────────────────┐
        │  Signal from Layer 4                  │
        │  (Direction, Entry, Stop, Target)     │
        └───────────────────────────────────────┘
                         │
                         ▼
        ┌───────────────────────────────────────┐
        │  ENTRY EXECUTION                      │
        │  • Add entry slippage (1-2 pts)       │
        │  • Calculate costs (commission + CTT) │
        │  • Create Trade object                │
        └───────────────────────────────────────┘
                         │
                         ▼
        ┌───────────────────────────────────────┐
        │  POSITION MANAGEMENT (per bar)        │
        │                                       │
        │  1. Update MFE/MAE tracking           │
        │  2. Check breakeven activation (25pt) │
        │  3. Update trailing stop (ATR-based)  │
        │  4. Check stop hit                    │
        │  5. Check target hit                  │
        │  6. Check time exit (8 hours)         │
        └───────────────────────────────────────┘
                         │
                         ▼
        ┌───────────────────────────────────────┐
        │  EXIT EXECUTION                       │
        │  • Add exit slippage (stop=2pt, TP=0.5pt)│
        │  • Calculate final P&L                │
        │  • Record exit reason                 │
        └───────────────────────────────────────┘

Two-Phase Stop Management

Phase 1: Breakeven Stop

Once trade is profitable by 25 points, move stop to entry price + buffer:

IF current_profit >= 25 points:

    LONG:  stop = entry_price + 2 (buffer)
    SHORT: stop = entry_price - 2 (buffer)

Purpose: Lock in a no-loss trade (or small profit with buffer).

Phase 2: Trailing Stop

After profit exceeds activation threshold, trail stop behind price:

Trailing Distance = ATR × 2.0 (minimum 15 points)

LONG:
    IF profit >= 20 points:
        new_stop = current_high - trailing_distance
        IF new_stop > current_stop:
            current_stop = new_stop  // Only moves UP

SHORT:
    IF profit >= 20 points:
        new_stop = current_low + trailing_distance
        IF new_stop < current_stop:
            current_stop = new_stop  // Only moves DOWN

Purpose: Let winners run while protecting accumulated profit.

ATR Calculation

ATR (Average True Range) measures volatility for adaptive trailing:

True Range = max(
    high - low,
    |high - previous_close|,
    |low - previous_close|
)

ATR = average(True Range over 14 bars)

Trailing Distance = ATR × 2.0

Effect:

High volatility → wider trailing stop (more room to breathe)
Low volatility → tighter trailing stop (protect more profit)

Slippage Model

Realistic slippage based on market conditions:

Entry Slippage

entry_slippage = base (1.0 pt)
               + position_impact (0.1 × lots, capped at 2.0)
               + volatility (0.5 pt)

Minimum: 0.5 points

Exit Slippage

Exit Type	Slippage	Reason
Stop Loss	2.0 points	Panic selling, worse fills
Take Profit	0.5 points	Limit order, better fills
Time Exit	0.0 points	Market order at close

MFE/MAE Tracking

Tracks Maximum Favorable and Adverse Excursion for each trade:

Metric	What It Measures	Usage
MFE	Best profit point reached during trade	Entry timing quality
MAE	Worst loss point during trade	Stop placement optimization

LONG:
    MFE = max profit seen = (highest_high - entry) × 100 × lots
    MAE = max loss seen = (lowest_low - entry) × 100 × lots

SHORT:
    MFE = max profit seen = (entry - lowest_low) × 100 × lots
    MAE = max loss seen = (entry - highest_high) × 100 × lots

Exit Conditions

Trades exit when any condition is met (checked in order):

Priority	Condition	Exit Price	Reason Code
1	Stop hit	stop_price - slippage (LONG)	"stop"
2	Target hit	target_price - slippage (LONG)	"target"
3	Time limit (8 hours)	current_close	"timeout"

Configuration

Parameter	Value	Description
`base_slippage_points`	1.0	Base entry slippage
`market_impact_factor`	0.1	Slippage per lot
`max_market_impact_slippage`	2.0	Cap on position slippage
`stop_loss_slippage`	2.0	Additional slippage on stops
`take_profit_slippage`	0.5	Reduced slippage on targets
`max_holding_period_minutes`	480	8 hours max holding
`enable_trailing_stop`	True	Enable trailing stop
`trailing_stop_method`	"ATR_MULTIPLE"	ATR-based or fixed
`atr_period`	14	ATR lookback period
`atr_multiplier`	2.0	Trailing = ATR × 2
`enable_breakeven_stop`	True	Enable breakeven
`breakeven_activation`	25.0	Points profit to activate
`breakeven_buffer`	2.0	Buffer above/below entry
`max_concurrent_trades`	3	Maximum open positions

Output

Trade Object (after exit):

Field	Type	Description
`entry_price`	float	Actual entry (with slippage)
`exit_price`	float	Actual exit (with slippage)
`exit_reason`	str	"stop", "target", "timeout"
`gross_pnl_inr`	float	P&L before costs
`net_pnl_inr`	float	P&L after commission + CTT
`brokerage_cost`	float	Commission paid
`tax_cost`	float	CTT paid
`max_favorable_excursion_inr`	float	Best P&L during trade
`max_adverse_excursion_inr`	float	Worst P&L during trade
`current_stop_price`	float	Final stop (after trailing)

Dependencies

Upstream:

signal_generation_trade_management.py - Provides signals to execute

Uses:

SignalGenerationTradeManagement.execute_signal() - For entry
SignalGenerationTradeManagement.close_trade() - For exit

Quick Reference

Event	Action
New signal received	Execute with slippage, create trade
Profit reaches 25pt	Move stop to breakeven (entry + 2pt)
Profit reaches 20pt	Start trailing stop (ATR × 2)
Price hits stop	Exit with 2pt slippage, reason="stop"
Price hits target	Exit with 0.5pt slippage, reason="target"
8 hours elapsed	Exit at market, reason="timeout"
Higher high (LONG)	Trail stop up if trailing active
Lower low (SHORT)	Trail stop down if trailing active