Merge pull request #9 from alphabench/feat/porfolio-simulation

feat: add Monte Carlo portfolio simulation and bump to 0.3.1
2026-02-17 00:36:45 +05:30 · 2026-02-17 00:35:20 +05:30 · 2026-02-10 05:05:38 +05:30 · 2026-02-10 05:03:39 +05:30 · 2026-02-08 06:06:30 +05:30 · 2026-02-08 06:04:43 +05:30
25 changed files with 2515 additions and 136 deletions
@@ -28,7 +28,7 @@ jobs:
        uses: PyO3/maturin-action@v1
        with:
          target: ${{ matrix.target }}
-          args: --release --out dist
+          args: --release --out dist -i python3.10 -i python3.11 -i python3.12
          manylinux: auto

      - name: Upload wheels
@@ -46,6 +46,11 @@ jobs:
    steps:
      - uses: actions/checkout@v4

+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.12'
+
      - name: Build wheels
        uses: PyO3/maturin-action@v1
        with:
@@ -67,6 +72,11 @@ jobs:
    steps:
      - uses: actions/checkout@v4

+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.12'
+
      - name: Build wheels
        uses: PyO3/maturin-action@v1
        with:
@@ -502,7 +502,7 @@ dependencies = [

 [[package]]
 name = "raptorbt"
-version = "0.1.0"
+version = "0.3.1"
 dependencies = [
 "approx",
 "criterion",
@@ -1,10 +1,15 @@
 [package]
 name = "raptorbt"
-version = "0.1.0"
+version = "0.3.1"
 edition = "2021"
-description = "High-performance Rust backtesting engine for Quant5"
-authors = ["Quant5 team"]
+description = "High-performance Rust backtesting engine with Python bindings. Drop-in VectorBT replacement with up insanely faster performance at fractional memory footprint."
+authors = ["Alphabench <contact@alphabench.in>"]
 license = "MIT"
+repository = "https://github.com/alphabench/raptorbt"
+homepage = "https://www.alphabench.in/raptorbt"
+readme = "README.md"
+keywords = ["backtesting", "trading", "quantitative-finance", "rust", "python"]
+categories = ["finance", "simulation"]

 [lib]
 name = "raptorbt"
@@ -1,6 +1,6 @@
 MIT License

-Copyright (c) 2024 Quant5 team
+Copyright (c) 2024 Alphabench

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
@@ -1,6 +1,51 @@
 # RaptorBT

-**RaptorBT** is a high-performance backtesting engine written in Rust with Python bindings via PyO3. It serves as a drop-in replacement for VectorBT, providing significant performance improvements while maintaining full metric parity.
+[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
+[![PyPI version](https://img.shields.io/pypi/v/raptorbt.svg)](https://pypi.org/project/raptorbt/)
+[![Python 3.10+](https://img.shields.io/badge/python-3.10+-blue.svg)](https://www.python.org/downloads/)
+[![Rust](https://img.shields.io/badge/rust-1.70+-red.svg)](https://www.rust-lang.org/)
+[![PyPI Downloads](https://static.pepy.tech/personalized-badge/raptorbt?period=total&units=INTERNATIONAL_SYSTEM&left_color=GRAY&right_color=ORANGE&left_text=downloads)](https://pepy.tech/projects/raptorbt)
+
+**Blazing-fast backtesting for the modern quant.**
+
+RaptorBT is a high-performance backtesting engine written in Rust with Python bindings via PyO3. It serves as a drop-in replacement for VectorBT — delivering **HFT-grade compute efficiency** with full metric parity.
+
+<p align="center">
+  <strong>5,800x faster</strong> · <strong>45x smaller</strong> · <strong>100% deterministic</strong>
+</p>
+
+---
+
+### Quick Install
+
+```bash
+pip install raptorbt
+```
+
+### 30-Second Example
+
+```python
+import numpy as np
+import raptorbt
+
+# Configure
+config = raptorbt.PyBacktestConfig(initial_capital=100000, fees=0.001)
+
+# Run backtest
+result = raptorbt.run_single_backtest(
+    timestamps=timestamps, open=open, high=high, low=low, close=close,
+    volume=volume, entries=entries, exits=exits,
+    direction=1, weight=1.0, symbol="AAPL", config=config,
+)
+
+# Results
+print(f"Return: {result.metrics.total_return_pct:.2f}%")
+print(f"Sharpe: {result.metrics.sharpe_ratio:.2f}")
+```
+
+---
+
+Developed and maintained by the [Alphabench](https://alphabench.in) team.

 ## Table of Contents

@@ -13,8 +58,7 @@
 - [Metrics](#metrics)
 - [Indicators](#indicators)
 - [Stop-Loss & Take-Profit](#stop-loss--take-profit)
- [Python Integration](#python-integration)
- [VectorBT Drop-in Replacement](#vectorbt-drop-in-replacement)
+- [VectorBT Comparison](#vectorbt-comparison)
 - [API Reference](#api-reference)
 - [Building from Source](#building-from-source)
 - [Testing](#testing)
@@ -23,7 +67,7 @@

 ## Overview

-RaptorBT was built to address the performance limitations of VectorBT in production environments:
+RaptorBT was built to address the performance limitations of VectorBT. Benchmarked by the Alphabench team:

 | Metric                        | VectorBT            | RaptorBT     | Improvement               |
 | ----------------------------- | ------------------- | ------------ | ------------------------- |
@@ -221,6 +265,9 @@ trades = result.trades()  # Returns list of PyTrade objects
 Basic long or short strategy on a single instrument.

 ```python
+# Optional: Instrument-specific configuration
+inst_config = raptorbt.PyInstrumentConfig(lot_size=1.0)
+
 result = raptorbt.run_single_backtest(
    timestamps=timestamps,
    open=open_prices, high=high_prices, low=low_prices,
@@ -230,6 +277,7 @@ result = raptorbt.run_single_backtest(
    weight=1.0,
    symbol="SYMBOL",
    config=config,
+    instrument_config=inst_config,  # Optional: lot_size rounding, capital caps
 )
 ```

@@ -244,10 +292,18 @@ instruments = [
    (timestamps, open3, high3, low3, close3, volume3, entries3, exits3, 1, 0.34, "MSFT"),
 ]

+# Optional: Per-instrument configs for lot_size and capital allocation
+instrument_configs = {
+    "AAPL": raptorbt.PyInstrumentConfig(lot_size=1.0, alloted_capital=33000),
+    "GOOGL": raptorbt.PyInstrumentConfig(lot_size=1.0, alloted_capital=33000),
+    "MSFT": raptorbt.PyInstrumentConfig(lot_size=1.0, alloted_capital=34000),
+}
+
 result = raptorbt.run_basket_backtest(
    instruments=instruments,
    config=config,
    sync_mode="all",  # "all", "any", "majority", "master"
+    instrument_configs=instrument_configs,  # Optional
 )
 ```

@@ -473,93 +529,75 @@ config.set_risk_reward_target(ratio=2.0)  # 2:1 risk-reward ratio

 ---

-## Python Integration
+## VectorBT Comparison

-RaptorBT integrates seamlessly with the Quant5 golf runner through `rpbt.py`.
+RaptorBT is designed as a drop-in replacement for VectorBT. Here's a side-by-side comparison:

-### Enable RaptorBT
-
-```bash
-export USE_RAPTORBT=1
-```
-
-Or in Python:
+### VectorBT (before)

 ```python
-import os
-os.environ["USE_RAPTORBT"] = "1"
-```
+import vectorbt as vbt
+import pandas as pd

-### Integration Functions
-
-```python
-from app.engine.golf.rpbt import (
-    is_raptorbt_enabled,
-    RaptorBTConfig,
-    RaptorBTPortfolioWrapper,
-    run_single_backtest_raptorbt,
-    run_basket_backtest_raptorbt,
-    run_pairs_backtest_raptorbt,
-    run_options_backtest_raptorbt,
-    run_multi_backtest_raptorbt,
+# Run backtest
+pf = vbt.Portfolio.from_signals(
+    close=close_series,
+    entries=entries,
+    exits=exits,
+    init_cash=100000,
+    fees=0.001,
 )

-# Check if RaptorBT is enabled
-if is_raptorbt_enabled():
-    print("Using RaptorBT backend")
+# Get metrics
+print(pf.stats()["Total Return [%]"])
+print(pf.stats()["Sharpe Ratio"])
+print(pf.stats()["Max Drawdown [%]"])
 ```

---
-
-## VectorBT Drop-in Replacement
-
-RaptorBT provides a `RaptorBTPortfolioWrapper` that mimics the VectorBT Portfolio interface:
+### RaptorBT (after)

 ```python
-from app.engine.golf.rpbt import (
-    RaptorBTPortfolioWrapper,
-    run_single_backtest_raptorbt,
-    RaptorBTConfig,
+import raptorbt
+import numpy as np
+
+# Configure backtest
+config = raptorbt.PyBacktestConfig(
+    initial_capital=100000,
+    fees=0.001,
 )

 # Run backtest
-result = run_single_backtest_raptorbt(compiled, ohlcv_df, config, symbol)
+result = raptorbt.run_single_backtest(
+    timestamps=timestamps,
+    open=open_prices, high=high_prices,
+    low=low_prices, close=close_prices,
+    volume=volume,
+    entries=entries, exits=exits,
+    direction=1, weight=1.0,
+    symbol="SYMBOL",
+    config=config,
+)

-# Wrap result for VectorBT compatibility
-portfolio = RaptorBTPortfolioWrapper(result)
-
-# Use like VectorBT Portfolio
-stats = portfolio.stats()           # Returns pd.Series with VectorBT-format keys
-equity = portfolio.value()          # Returns equity curve as pd.Series
-dd = portfolio.drawdown()           # Returns drawdown curve as pd.Series
-trades_df = portfolio.trades()      # Returns trades as pd.DataFrame
-
-# Access properties
-print(portfolio.total_return)       # Total return percentage
-print(portfolio.sharpe_ratio)       # Sharpe ratio
-print(portfolio.max_drawdown)       # Max drawdown percentage
-print(portfolio.win_rate)           # Win rate percentage
-print(portfolio.profit_factor)      # Profit factor
-print(portfolio.sqn)                # System Quality Number
-print(portfolio.expectancy)         # Expected value per trade
-print(portfolio.omega_ratio)        # Omega ratio
+# Get metrics
+print(f"Total Return: {result.metrics.total_return_pct}%")
+print(f"Sharpe Ratio: {result.metrics.sharpe_ratio}")
+print(f"Max Drawdown: {result.metrics.max_drawdown_pct}%")
 ```

-### Stats Format
+### Metric Mapping

-The `stats()` method returns a pandas Series with VectorBT-compatible keys:
-
-```python
-stats = portfolio.stats()
-print(stats["Total Return [%]"])
-print(stats["Sharpe Ratio"])
-print(stats["Max Drawdown [%]"])
-print(stats["Win Rate [%]"])
-print(stats["Profit Factor"])
-print(stats["SQN"])
-print(stats["Omega Ratio"])
-# ... and 20+ more metrics
-```
+| VectorBT Key       | RaptorBT Attribute         |
+| ------------------ | -------------------------- |
+| `Total Return [%]` | `metrics.total_return_pct` |
+| `Sharpe Ratio`     | `metrics.sharpe_ratio`     |
+| `Sortino Ratio`    | `metrics.sortino_ratio`    |
+| `Max Drawdown [%]` | `metrics.max_drawdown_pct` |
+| `Win Rate [%]`     | `metrics.win_rate_pct`     |
+| `Profit Factor`    | `metrics.profit_factor`    |
+| `SQN`              | `metrics.sqn`              |
+| `Omega Ratio`      | `metrics.omega_ratio`      |
+| `Total Trades`     | `metrics.total_trades`     |
+| `Expectancy`       | `metrics.expectancy`       |

 ---

@@ -586,6 +624,29 @@ config.set_atr_target(multiplier: float, period: int)
 config.set_risk_reward_target(ratio: float)
 ```

+### PyInstrumentConfig
+
+Per-instrument configuration for position sizing and risk management.
+
+```python
+inst_config = raptorbt.PyInstrumentConfig(
+    lot_size=1.0,              # Min tradeable quantity (1 for equity, 50 for NIFTY F&O)
+    alloted_capital=50000.0,   # Capital allocated to this instrument (optional)
+    existing_qty=None,         # Existing position quantity (future use)
+    avg_price=None,            # Existing position avg price (future use)
+)
+
+# Optional: per-instrument stop/target overrides
+inst_config.set_fixed_stop(0.02)
+inst_config.set_trailing_stop(0.03)
+inst_config.set_fixed_target(0.05)
+```
+
+**Fields:**
+- `lot_size` - Minimum tradeable quantity. Position sizes are rounded down to nearest lot_size multiple. Use `1.0` for equities, `50.0` for NIFTY F&O, `0.01` for forex.
+- `alloted_capital` - Per-instrument capital cap (capped at available cash).
+- `existing_qty` / `avg_price` - Reserved for future live-to-backtest transitions.
+
 ### PyBacktestResult

 ```python
@@ -686,12 +747,6 @@ maturin build --release
 pip install target/wheels/raptorbt-*.whl
 ```

-### Using the Build Script
-
-```bash
-./scripts/build-engine.sh --install
-```
-
 ---

 ## Testing
@@ -705,9 +760,7 @@ cargo test

 ### Python Integration Tests

-```bash
-# Test basic functionality
-uv run python -c "
+```python
 import raptorbt
 import numpy as np

@@ -728,13 +781,11 @@ result = raptorbt.run_single_backtest(
 )
 print(f'Total Return: {result.metrics.total_return_pct:.2f}%')
 print('RaptorBT is working correctly!')
-"
 ```

 ### Comparison Test (VectorBT vs RaptorBT)

-```bash
-USE_RAPTORBT=1 uv run python << 'EOF'
+```python
 import numpy as np
 import pandas as pd
 import vectorbt as vbt
@@ -769,26 +820,51 @@ result = raptorbt.run_single_backtest(

 print(f"VectorBT: {pf.stats()['Total Return [%]']:.4f}%")
 print(f"RaptorBT: {result.metrics.total_return_pct:.4f}%")
-print(f"Match: {abs(pf.stats()['Total Return [%]'] - result.metrics.total_return_pct) < 0.01}")
-EOF
+# Results should match within 0.01%
 ```

 ---

 ## License

-RaptorBT is proprietary software developed for the Quant5 platform.
+MIT License - see [LICENSE](LICENSE) for details.

 ---

 ## Changelog

-### v0.1.0 (2024-01)
+### v0.3.0
+
+- Per-instrument configuration via `PyInstrumentConfig` (lot_size, alloted_capital, stop/target overrides)
+- Position sizes now correctly rounded to lot_size multiples
+- Support for per-instrument capital allocation in basket backtests
+- Future-ready fields: existing_qty, avg_price for live-to-backtest transitions
+
+### v0.2.2
+
+- Export `run_spread_backtest` Python binding for multi-leg options spread strategies
+- Export `rolling_min` and `rolling_max` indicator functions to Python
+
+### v0.2.1
+
+- Add `rolling_min` and `rolling_max` indicators for LLV (Lowest Low Value) and HHV (Highest High Value) support
+- NaN handling for warmup period
+
+### v0.2.0
+
+- Add multi-leg spread backtesting (`run_spread_backtest`) supporting straddles, strangles, vertical spreads, iron condors, iron butterflies, butterfly spreads, calendar spreads, and diagonal spreads
+- Coordinated entry/exit across all legs with net premium P&L calculation
+- Max loss and target profit exit thresholds for spreads
+- Add `SessionTracker` for intraday session management: market hours detection, squareoff time enforcement, session high/low/open tracking
+- Pre-built session configs for NSE equity (9:15-15:30), MCX commodity (9:00-23:30), and CDS currency (9:00-17:00)
+- Extend `StreamingMetrics` with equity/drawdown tracking, trade recording, and `finalize()` method
+
+### v0.1.0

 - Initial release
 - 5 strategy types: single, basket, pairs, options, multi
- 30+ performance metrics
- 10 technical indicators
- Fixed, ATR, and trailing stops
- PyO3 Python bindings
- VectorBT-compatible wrapper
+- 30+ performance metrics with full VectorBT parity
+- 10 technical indicators (SMA, EMA, RSI, MACD, Stochastic, ATR, Bollinger Bands, ADX, VWAP, Supertrend)
+- Stop-loss management: fixed, ATR-based, and trailing stops
+- Take-profit management: fixed, ATR-based, and risk-reward targets
+- PyO3 Python bindings for seamless Python integration
@@ -4,13 +4,13 @@ build-backend = "maturin"

 [project]
 name = "raptorbt"
-version = "0.1.0"
-description = "High-performance Rust backtesting engine with Python bindings"
+version = "0.3.1"
+description = "High-performance Rust backtesting engine with Python bindings. Drop-in VectorBT replacement with up insanely faster performance at fractional memory footprint."
 readme = "README.md"
 requires-python = ">=3.10"
 license = {file = "LICENSE"}
 authors = [
-    {name = "Quant5 team"}
+    {name = "Alphabench", email = "contact@alphabench.in"}
 ]
 keywords = [
    "backtesting",
@@ -39,9 +39,9 @@ classifiers = [
 ]

 [project.urls]
-Homepage = "https://github.com/alphabench/raptorbt"
+Homepage = "https://www.alphabench.in/raptorbt"
 Repository = "https://github.com/alphabench/raptorbt"
-Documentation = "https://github.com/alphabench/raptorbt#readme"
+Documentation = "https://www.alphabench.in/raptorbt"
 "Bug Tracker" = "https://github.com/alphabench/raptorbt/issues"

 [tool.maturin]
@@ -1,5 +1,5 @@
 """
-RaptorBT - High-performance Rust backtesting engine for Quant5.
+RaptorBT - High-performance Rust backtesting engine.

 This module provides Python bindings for the Rust-based backtesting engine,
 offering significant performance improvements over vectorbt:
@@ -12,6 +12,7 @@ offering significant performance improvements over vectorbt:
 from raptorbt._raptorbt import (
    # Config classes
    PyBacktestConfig,
+    PyInstrumentConfig,
    PyStopConfig,
    PyTargetConfig,
    # Result classes
@@ -24,6 +25,9 @@ from raptorbt._raptorbt import (
    run_options_backtest,
    run_pairs_backtest,
    run_multi_backtest,
+    run_spread_backtest,
+    # Monte Carlo simulation
+    simulate_portfolio_mc,
    # Indicator functions
    sma,
    ema,
@@ -35,13 +39,16 @@ from raptorbt._raptorbt import (
    adx,
    vwap,
    supertrend,
+    rolling_min,
+    rolling_max,
 )

-__version__ = "0.1.0"
+__version__ = "0.3.1"

 __all__ = [
    # Config classes
    "PyBacktestConfig",
+    "PyInstrumentConfig",
    "PyStopConfig",
    "PyTargetConfig",
    # Result classes
@@ -54,6 +61,9 @@ __all__ = [
    "run_options_backtest",
    "run_pairs_backtest",
    "run_multi_backtest",
+    "run_spread_backtest",
+    # Monte Carlo simulation
+    "simulate_portfolio_mc",
    # Indicator functions
    "sma",
    "ema",
@@ -65,4 +75,6 @@ __all__ = [
    "adx",
    "vwap",
    "supertrend",
+    "rolling_min",
+    "rolling_max",
 ]
@@ -1,9 +1,11 @@
 //! Core types and utilities for RaptorBT.

 pub mod error;
+pub mod session;
 pub mod timeseries;
 pub mod types;

 pub use error::{RaptorError, Result};
+pub use session::{SessionConfig, SessionTracker};
 pub use timeseries::TimeSeries;
 pub use types::*;
@@ -0,0 +1,397 @@
+//! Session tracking for intraday strategies.
+//!
+//! Handles:
+//! - Session boundary detection (market open/close)
+//! - Squareoff time enforcement
+//! - Session high/low tracking for ORB and session-based indicators
+//! - Timezone handling for IST (India Standard Time)
+
+use serde::{Deserialize, Serialize};
+
+/// Session configuration for trading hours.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct SessionConfig {
+    /// Market open hour (24-hour format).
+    pub market_open_hour: u32,
+    /// Market open minute.
+    pub market_open_minute: u32,
+    /// Market close hour (24-hour format).
+    pub market_close_hour: u32,
+    /// Market close minute.
+    pub market_close_minute: u32,
+    /// Squareoff minutes before market close.
+    pub squareoff_minutes_before_close: u32,
+    /// Timezone offset in hours from UTC (5 for IST = UTC+5:30).
+    pub timezone_offset_hours: i32,
+    /// Timezone offset minutes (30 for IST).
+    pub timezone_offset_minutes: i32,
+}
+
+impl Default for SessionConfig {
+    fn default() -> Self {
+        // Default: NSE equity session (9:15 - 15:30 IST, squareoff at 15:25)
+        Self {
+            market_open_hour: 9,
+            market_open_minute: 15,
+            market_close_hour: 15,
+            market_close_minute: 30,
+            squareoff_minutes_before_close: 5,
+            timezone_offset_hours: 5,
+            timezone_offset_minutes: 30,
+        }
+    }
+}
+
+impl SessionConfig {
+    /// Create NSE equity session config (9:15 - 15:30).
+    pub fn nse_equity() -> Self {
+        Self::default()
+    }
+
+    /// Create MCX commodity session config (9:00 - 23:30).
+    pub fn mcx_commodity() -> Self {
+        Self {
+            market_open_hour: 9,
+            market_open_minute: 0,
+            market_close_hour: 23,
+            market_close_minute: 30,
+            squareoff_minutes_before_close: 5,
+            timezone_offset_hours: 5,
+            timezone_offset_minutes: 30,
+        }
+    }
+
+    /// Create CDS currency session config (9:00 - 17:00).
+    pub fn cds_currency() -> Self {
+        Self {
+            market_open_hour: 9,
+            market_open_minute: 0,
+            market_close_hour: 17,
+            market_close_minute: 0,
+            squareoff_minutes_before_close: 5,
+            timezone_offset_hours: 5,
+            timezone_offset_minutes: 30,
+        }
+    }
+
+    /// Get market open time in minutes from midnight.
+    pub fn market_open_minutes(&self) -> u32 {
+        self.market_open_hour * 60 + self.market_open_minute
+    }
+
+    /// Get market close time in minutes from midnight.
+    pub fn market_close_minutes(&self) -> u32 {
+        self.market_close_hour * 60 + self.market_close_minute
+    }
+
+    /// Get squareoff time in minutes from midnight.
+    pub fn squareoff_minutes(&self) -> u32 {
+        self.market_close_minutes().saturating_sub(self.squareoff_minutes_before_close)
+    }
+
+    /// Get timezone offset in seconds.
+    pub fn timezone_offset_seconds(&self) -> i64 {
+        (self.timezone_offset_hours as i64 * 3600) + (self.timezone_offset_minutes as i64 * 60)
+    }
+}
+
+/// Session tracker for managing intraday session state.
+#[derive(Debug, Clone)]
+pub struct SessionTracker {
+    config: SessionConfig,
+    /// Current session date (days since epoch in local timezone).
+    current_session_date: i64,
+    /// Session high price.
+    session_high: f64,
+    /// Session low price.
+    session_low: f64,
+    /// Session open price.
+    session_open: f64,
+    /// Bar index at session start.
+    session_start_idx: usize,
+    /// Whether we're currently in a trading session.
+    in_session: bool,
+    /// Whether squareoff has been triggered today.
+    squareoff_triggered: bool,
+}
+
+impl SessionTracker {
+    /// Create a new session tracker.
+    pub fn new(config: SessionConfig) -> Self {
+        Self {
+            config,
+            current_session_date: -1,
+            session_high: f64::NEG_INFINITY,
+            session_low: f64::INFINITY,
+            session_open: 0.0,
+            session_start_idx: 0,
+            in_session: false,
+            squareoff_triggered: false,
+        }
+    }
+
+    /// Convert nanosecond timestamp to local time components.
+    fn timestamp_to_local(&self, timestamp_ns: i64) -> (i64, u32, u32, u32) {
+        // Convert to seconds
+        let timestamp_s = timestamp_ns / 1_000_000_000;
+
+        // Apply timezone offset
+        let local_s = timestamp_s + self.config.timezone_offset_seconds();
+
+        // Calculate date (days since epoch)
+        let days = local_s / 86400;
+
+        // Calculate time within day
+        let time_in_day = (local_s % 86400) as u32;
+        let hours = time_in_day / 3600;
+        let minutes = (time_in_day % 3600) / 60;
+        let seconds = time_in_day % 60;
+
+        (days, hours, minutes, seconds)
+    }
+
+    /// Get minutes from midnight for a timestamp.
+    fn get_minutes_from_midnight(&self, timestamp_ns: i64) -> u32 {
+        let (_, hours, minutes, _) = self.timestamp_to_local(timestamp_ns);
+        hours * 60 + minutes
+    }
+
+    /// Check if timestamp is within trading hours.
+    pub fn is_within_trading_hours(&self, timestamp_ns: i64) -> bool {
+        let minutes = self.get_minutes_from_midnight(timestamp_ns);
+        minutes >= self.config.market_open_minutes() && minutes < self.config.market_close_minutes()
+    }
+
+    /// Check if it's squareoff time.
+    pub fn is_squareoff_time(&self, timestamp_ns: i64) -> bool {
+        let minutes = self.get_minutes_from_midnight(timestamp_ns);
+        minutes >= self.config.squareoff_minutes()
+    }
+
+    /// Check if this bar starts a new session.
+    pub fn is_session_start(&self, prev_ts_ns: i64, curr_ts_ns: i64) -> bool {
+        let (prev_date, prev_h, prev_m, _) = self.timestamp_to_local(prev_ts_ns);
+        let (curr_date, curr_h, curr_m, _) = self.timestamp_to_local(curr_ts_ns);
+
+        // New day
+        if curr_date != prev_date {
+            let curr_minutes = curr_h * 60 + curr_m;
+            return curr_minutes >= self.config.market_open_minutes();
+        }
+
+        // Same day, but crossed market open
+        let prev_minutes = prev_h * 60 + prev_m;
+        let curr_minutes = curr_h * 60 + curr_m;
+
+        prev_minutes < self.config.market_open_minutes()
+            && curr_minutes >= self.config.market_open_minutes()
+    }
+
+    /// Check if this bar ends the session.
+    pub fn is_session_end(&self, curr_ts_ns: i64, next_ts_ns: Option<i64>) -> bool {
+        let (curr_date, curr_h, curr_m, _) = self.timestamp_to_local(curr_ts_ns);
+        let curr_minutes = curr_h * 60 + curr_m;
+
+        // At or past market close
+        if curr_minutes >= self.config.market_close_minutes() {
+            return true;
+        }
+
+        // Check if next bar is in a new session
+        if let Some(next_ts) = next_ts_ns {
+            let (next_date, _, _, _) = self.timestamp_to_local(next_ts);
+            if next_date != curr_date {
+                return true;
+            }
+        }
+
+        false
+    }
+
+    /// Update session state for a new bar.
+    ///
+    /// Returns tuple of (is_new_session, is_squareoff_time, is_session_end).
+    pub fn update(
+        &mut self,
+        idx: usize,
+        timestamp_ns: i64,
+        open: f64,
+        high: f64,
+        low: f64,
+        _close: f64,
+        prev_timestamp_ns: Option<i64>,
+        next_timestamp_ns: Option<i64>,
+    ) -> (bool, bool, bool) {
+        let (date, hours, minutes, _) = self.timestamp_to_local(timestamp_ns);
+        let time_minutes = hours * 60 + minutes;
+
+        // Check for new session
+        let is_new_session = if self.current_session_date != date {
+            // New date - check if within trading hours
+            if time_minutes >= self.config.market_open_minutes()
+                && time_minutes < self.config.market_close_minutes()
+            {
+                self.reset_session(idx, date, open);
+                true
+            } else {
+                false
+            }
+        } else if let Some(prev_ts) = prev_timestamp_ns {
+            if self.is_session_start(prev_ts, timestamp_ns) {
+                self.reset_session(idx, date, open);
+                true
+            } else {
+                false
+            }
+        } else {
+            // First bar - start session if within hours
+            if time_minutes >= self.config.market_open_minutes()
+                && time_minutes < self.config.market_close_minutes()
+            {
+                self.reset_session(idx, date, open);
+                true
+            } else {
+                false
+            }
+        };
+
+        // Update session high/low
+        if self.in_session {
+            if high > self.session_high {
+                self.session_high = high;
+            }
+            if low < self.session_low {
+                self.session_low = low;
+            }
+        }
+
+        // Check squareoff time
+        let is_squareoff =
+            if time_minutes >= self.config.squareoff_minutes() && !self.squareoff_triggered {
+                self.squareoff_triggered = true;
+                self.in_session
+            } else {
+                false
+            };
+
+        // Check session end
+        let is_session_end = self.is_session_end(timestamp_ns, next_timestamp_ns);
+        if is_session_end {
+            self.in_session = false;
+        }
+
+        (is_new_session, is_squareoff, is_session_end)
+    }
+
+    /// Reset session state for a new trading day.
+    fn reset_session(&mut self, idx: usize, date: i64, open_price: f64) {
+        self.current_session_date = date;
+        self.session_start_idx = idx;
+        self.session_open = open_price;
+        self.session_high = open_price;
+        self.session_low = open_price;
+        self.in_session = true;
+        self.squareoff_triggered = false;
+    }
+
+    /// Get current session high.
+    pub fn session_high(&self) -> f64 {
+        self.session_high
+    }
+
+    /// Get current session low.
+    pub fn session_low(&self) -> f64 {
+        self.session_low
+    }
+
+    /// Get current session open.
+    pub fn session_open(&self) -> f64 {
+        self.session_open
+    }
+
+    /// Get session start index.
+    pub fn session_start_idx(&self) -> usize {
+        self.session_start_idx
+    }
+
+    /// Check if currently in a trading session.
+    pub fn in_session(&self) -> bool {
+        self.in_session
+    }
+
+    /// Get opening range (high - low) for the session.
+    pub fn opening_range(&self) -> f64 {
+        self.session_high - self.session_low
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn make_timestamp(year: i32, month: u32, day: u32, hour: u32, minute: u32) -> i64 {
+        // Simplified: calculate seconds from 1970-01-01 and convert to nanoseconds
+        // This is approximate for testing
+        let days_since_epoch = (year - 1970) as i64 * 365 + (month - 1) as i64 * 30 + day as i64;
+        let seconds = days_since_epoch * 86400 + hour as i64 * 3600 + minute as i64 * 60;
+        // Subtract IST offset to get UTC
+        let utc_seconds = seconds - (5 * 3600 + 30 * 60);
+        utc_seconds * 1_000_000_000
+    }
+
+    #[test]
+    fn test_session_config_defaults() {
+        let config = SessionConfig::default();
+        assert_eq!(config.market_open_hour, 9);
+        assert_eq!(config.market_open_minute, 15);
+        assert_eq!(config.market_close_hour, 15);
+        assert_eq!(config.market_close_minute, 30);
+        assert_eq!(config.squareoff_minutes_before_close, 5);
+    }
+
+    #[test]
+    fn test_squareoff_minutes() {
+        let config = SessionConfig::default();
+        // 15:30 - 5 minutes = 15:25 = 925 minutes
+        assert_eq!(config.squareoff_minutes(), 925);
+    }
+
+    #[test]
+    fn test_mcx_session() {
+        let config = SessionConfig::mcx_commodity();
+        assert_eq!(config.market_open_hour, 9);
+        assert_eq!(config.market_close_hour, 23);
+        assert_eq!(config.market_close_minute, 30);
+    }
+
+    #[test]
+    fn test_session_tracker_new_session() {
+        let config = SessionConfig::default();
+        let mut tracker = SessionTracker::new(config);
+
+        // Simulate market open at 9:15 IST
+        let ts = make_timestamp(2024, 1, 15, 9, 15);
+        let (is_new, _, _) = tracker.update(0, ts, 100.0, 101.0, 99.0, 100.5, None, None);
+
+        assert!(is_new);
+        assert!(tracker.in_session());
+        assert_eq!(tracker.session_open(), 100.0);
+    }
+
+    #[test]
+    fn test_session_high_low() {
+        let config = SessionConfig::default();
+        let mut tracker = SessionTracker::new(config);
+
+        // First bar
+        let ts1 = make_timestamp(2024, 1, 15, 9, 15);
+        tracker.update(0, ts1, 100.0, 105.0, 95.0, 102.0, None, None);
+
+        // Second bar
+        let ts2 = make_timestamp(2024, 1, 15, 9, 30);
+        tracker.update(1, ts2, 102.0, 110.0, 100.0, 108.0, Some(ts1), None);
+
+        assert_eq!(tracker.session_high(), 110.0);
+        assert_eq!(tracker.session_low(), 95.0);
+    }
+}
@@ -244,6 +244,47 @@ impl Default for BacktestConfig {
    }
 }

+/// Per-instrument configuration for position sizing and risk management.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct InstrumentConfig {
+    /// Minimum tradeable quantity (1.0 for NSE EQ, 50.0 for NIFTY F&O, 0.01 for forex).
+    pub lot_size: Option<f64>,
+    /// Per-instrument capital cap.
+    pub alloted_capital: Option<f64>,
+    /// Per-instrument stop override.
+    pub stop: Option<StopConfig>,
+    /// Per-instrument target override.
+    pub target: Option<TargetConfig>,
+    /// Existing position quantity (future use).
+    pub existing_qty: Option<f64>,
+    /// Existing position average price (future use).
+    pub avg_price: Option<f64>,
+}
+
+impl InstrumentConfig {
+    /// Round a raw position size down to the nearest lot_size multiple.
+    /// Returns raw_size unchanged if lot_size is None or <= 0.
+    pub fn round_to_lot(&self, raw_size: f64) -> f64 {
+        match self.lot_size {
+            Some(lot) if lot > 0.0 => (raw_size / lot).floor() * lot,
+            _ => raw_size,
+        }
+    }
+}
+
+impl Default for InstrumentConfig {
+    fn default() -> Self {
+        Self {
+            lot_size: None,
+            alloted_capital: None,
+            stop: None,
+            target: None,
+            existing_qty: None,
+            avg_price: None,
+        }
+    }
+}
+
 /// Stop-loss configuration.
 #[derive(Debug, Clone, Copy, Serialize, Deserialize)]
 pub enum StopConfig {
@@ -460,3 +501,49 @@ impl Default for Position {
        Self::new()
    }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_round_to_lot_whole_shares() {
+        let config = InstrumentConfig { lot_size: Some(1.0), ..Default::default() };
+        assert_eq!(config.round_to_lot(242.47), 242.0);
+        assert_eq!(config.round_to_lot(1.0), 1.0);
+        assert_eq!(config.round_to_lot(0.5), 0.0);
+    }
+
+    #[test]
+    fn test_round_to_lot_nifty_fo() {
+        let config = InstrumentConfig { lot_size: Some(50.0), ..Default::default() };
+        assert_eq!(config.round_to_lot(242.0), 200.0);
+        assert_eq!(config.round_to_lot(50.0), 50.0);
+        assert_eq!(config.round_to_lot(49.0), 0.0);
+        assert_eq!(config.round_to_lot(150.0), 150.0);
+    }
+
+    #[test]
+    fn test_round_to_lot_fractional() {
+        let config = InstrumentConfig { lot_size: Some(0.01), ..Default::default() };
+        assert!((config.round_to_lot(1.234) - 1.23).abs() < 1e-10);
+    }
+
+    #[test]
+    fn test_round_to_lot_none() {
+        let config = InstrumentConfig::default();
+        assert_eq!(config.round_to_lot(242.47), 242.47);
+    }
+
+    #[test]
+    fn test_round_to_lot_zero() {
+        let config = InstrumentConfig { lot_size: Some(0.0), ..Default::default() };
+        assert_eq!(config.round_to_lot(242.47), 242.47);
+    }
+
+    #[test]
+    fn test_round_to_lot_negative() {
+        let config = InstrumentConfig { lot_size: Some(-1.0), ..Default::default() };
+        assert_eq!(config.round_to_lot(242.47), 242.47);
+    }
+}
@@ -4,12 +4,14 @@
 //! and return Vec outputs. NaN values are used for the warmup period.

 pub mod momentum;
+pub mod rolling;
 pub mod strength;
 pub mod trend;
 pub mod volatility;
 pub mod volume;

 pub use momentum::{macd, rsi, stochastic, MacdResult, StochasticResult};
+pub use rolling::{rolling_max, rolling_min};
 pub use strength::adx;
 pub use trend::{ema, sma, supertrend, SupertrendResult};
 pub use volatility::{atr, bollinger_bands, BollingerBandsResult};
@@ -0,0 +1,106 @@
+//! Rolling min/max indicators for LLV/HHV support.
+//!
+//! Provides rolling minimum and maximum calculations for Lowest Low Value (LLV)
+//! and Highest High Value (HHV) expressions.
+
+use crate::core::error::RaptorError;
+
+/// Calculate rolling minimum (Lowest Low Value) over a period.
+///
+/// Returns NaN for the first (period - 1) values where insufficient data exists.
+///
+/// # Arguments
+/// * `data` - Input data slice
+/// * `period` - Lookback period
+///
+/// # Returns
+/// Vec of rolling minimum values
+pub fn rolling_min(data: &[f64], period: usize) -> Result<Vec<f64>, RaptorError> {
+    if period == 0 {
+        return Err(RaptorError::invalid_parameter("period must be at least 1"));
+    }
+
+    let n = data.len();
+    let mut result = vec![f64::NAN; n];
+
+    for i in (period - 1)..n {
+        let start = i + 1 - period;
+        let min_val =
+            data[start..=i]
+                .iter()
+                .fold(f64::INFINITY, |a, &b| if b.is_nan() { a } else { a.min(b) });
+        result[i] = if min_val == f64::INFINITY { f64::NAN } else { min_val };
+    }
+
+    Ok(result)
+}
+
+/// Calculate rolling maximum (Highest High Value) over a period.
+///
+/// Returns NaN for the first (period - 1) values where insufficient data exists.
+///
+/// # Arguments
+/// * `data` - Input data slice
+/// * `period` - Lookback period
+///
+/// # Returns
+/// Vec of rolling maximum values
+pub fn rolling_max(data: &[f64], period: usize) -> Result<Vec<f64>, RaptorError> {
+    if period == 0 {
+        return Err(RaptorError::invalid_parameter("period must be at least 1"));
+    }
+
+    let n = data.len();
+    let mut result = vec![f64::NAN; n];
+
+    for i in (period - 1)..n {
+        let start = i + 1 - period;
+        let max_val =
+            data[start..=i]
+                .iter()
+                .fold(f64::NEG_INFINITY, |a, &b| if b.is_nan() { a } else { a.max(b) });
+        result[i] = if max_val == f64::NEG_INFINITY { f64::NAN } else { max_val };
+    }
+
+    Ok(result)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_rolling_min() {
+        let data = vec![5.0, 3.0, 8.0, 2.0, 7.0, 1.0, 9.0];
+        let result = rolling_min(&data, 3).unwrap();
+
+        assert!(result[0].is_nan());
+        assert!(result[1].is_nan());
+        assert!((result[2] - 3.0).abs() < f64::EPSILON); // min(5, 3, 8)
+        assert!((result[3] - 2.0).abs() < f64::EPSILON); // min(3, 8, 2)
+        assert!((result[4] - 2.0).abs() < f64::EPSILON); // min(8, 2, 7)
+        assert!((result[5] - 1.0).abs() < f64::EPSILON); // min(2, 7, 1)
+        assert!((result[6] - 1.0).abs() < f64::EPSILON); // min(7, 1, 9)
+    }
+
+    #[test]
+    fn test_rolling_max() {
+        let data = vec![5.0, 3.0, 8.0, 2.0, 7.0, 1.0, 9.0];
+        let result = rolling_max(&data, 3).unwrap();
+
+        assert!(result[0].is_nan());
+        assert!(result[1].is_nan());
+        assert!((result[2] - 8.0).abs() < f64::EPSILON); // max(5, 3, 8)
+        assert!((result[3] - 8.0).abs() < f64::EPSILON); // max(3, 8, 2)
+        assert!((result[4] - 8.0).abs() < f64::EPSILON); // max(8, 2, 7)
+        assert!((result[5] - 7.0).abs() < f64::EPSILON); // max(2, 7, 1)
+        assert!((result[6] - 9.0).abs() < f64::EPSILON); // max(7, 1, 9)
+    }
+
+    #[test]
+    fn test_invalid_period() {
+        let data = vec![1.0, 2.0, 3.0];
+        assert!(rolling_min(&data, 0).is_err());
+        assert!(rolling_max(&data, 0).is_err());
+    }
+}
@@ -1,7 +1,7 @@
 // Suppress warning from PyO3 macro expansion (fixed in newer PyO3 versions)
 #![allow(non_local_definitions)]

-//! RaptorBT - High-performance Rust backtesting engine for Quant5.
+//! RaptorBT - High-performance Rust backtesting engine.
 //!
 //! This crate provides a complete backtesting solution with:
 //! - Technical indicators (SMA, EMA, RSI, MACD, etc.)
@@ -27,6 +27,7 @@ pub mod strategies;
 fn _raptorbt(_py: Python<'_>, m: &PyModule) -> PyResult<()> {
    // Register config classes
    m.add_class::<python::bindings::PyBacktestConfig>()?;
+    m.add_class::<python::bindings::PyInstrumentConfig>()?;
    m.add_class::<python::bindings::PyStopConfig>()?;
    m.add_class::<python::bindings::PyTargetConfig>()?;

@@ -41,6 +42,10 @@ fn _raptorbt(_py: Python<'_>, m: &PyModule) -> PyResult<()> {
    m.add_function(wrap_pyfunction!(python::bindings::run_options_backtest, m)?)?;
    m.add_function(wrap_pyfunction!(python::bindings::run_pairs_backtest, m)?)?;
    m.add_function(wrap_pyfunction!(python::bindings::run_multi_backtest, m)?)?;
+    m.add_function(wrap_pyfunction!(python::bindings::run_spread_backtest, m)?)?;
+
+    // Register Monte Carlo simulation
+    m.add_function(wrap_pyfunction!(python::bindings::simulate_portfolio_mc, m)?)?;

    // Register indicator functions
    m.add_function(wrap_pyfunction!(python::bindings::sma, m)?)?;
@@ -53,6 +58,8 @@ fn _raptorbt(_py: Python<'_>, m: &PyModule) -> PyResult<()> {
    m.add_function(wrap_pyfunction!(python::bindings::adx, m)?)?;
    m.add_function(wrap_pyfunction!(python::bindings::vwap, m)?)?;
    m.add_function(wrap_pyfunction!(python::bindings::supertrend, m)?)?;
+    m.add_function(wrap_pyfunction!(python::bindings::rolling_min, m)?)?;
+    m.add_function(wrap_pyfunction!(python::bindings::rolling_max, m)?)?;

    Ok(())
 }
@@ -2,9 +2,12 @@
 //!
 //! Enables single-pass calculation of mean, variance, Sharpe ratio, and Sortino ratio.

+use crate::core::types::BacktestMetrics;
+
 /// Streaming metrics calculator using Welford's algorithm.
 ///
 /// Allows incremental calculation of statistics without storing all values.
+/// Also tracks equity and drawdown for backtesting.
 #[derive(Debug, Clone)]
 pub struct StreamingMetrics {
    /// Number of observations.
@@ -27,6 +30,59 @@ pub struct StreamingMetrics {
    count_positive: usize,
    /// Count of negative returns.
    count_negative: usize,
+
+    // === Equity and drawdown tracking ===
+    /// Initial capital.
+    #[allow(dead_code)]
+    initial_capital: f64,
+    /// Peak equity value (for drawdown calculation).
+    peak_equity: f64,
+    /// Current equity value.
+    current_equity: f64,
+    /// Maximum drawdown percentage.
+    max_drawdown_pct: f64,
+    /// Current drawdown percentage.
+    current_drawdown: f64,
+    /// Bars since peak (for max drawdown duration).
+    bars_since_peak: usize,
+    /// Maximum drawdown duration in bars.
+    max_drawdown_duration: usize,
+
+    // === Trade tracking ===
+    /// Number of trades.
+    trade_count: usize,
+    /// Number of winning trades.
+    winning_trades: usize,
+    /// Number of losing trades.
+    losing_trades: usize,
+    /// Sum of winning trade P&L.
+    sum_wins: f64,
+    /// Sum of losing trade P&L.
+    sum_losses: f64,
+    /// Sum of trade return percentages.
+    sum_trade_returns: f64,
+    /// Sum of squared trade return percentages (for SQN).
+    sum_trade_returns_sq: f64,
+    /// Best trade return percentage.
+    best_trade_pct: f64,
+    /// Worst trade return percentage.
+    worst_trade_pct: f64,
+    /// Sum of winning trade durations.
+    sum_winning_duration: usize,
+    /// Sum of losing trade durations.
+    sum_losing_duration: usize,
+    /// Current consecutive wins.
+    current_consecutive_wins: usize,
+    /// Current consecutive losses.
+    current_consecutive_losses: usize,
+    /// Maximum consecutive wins.
+    max_consecutive_wins: usize,
+    /// Maximum consecutive losses.
+    max_consecutive_losses: usize,
+    /// Total holding period (bars).
+    total_holding_period: usize,
+    /// Total fees paid.
+    total_fees: f64,
 }

 impl Default for StreamingMetrics {
@@ -38,6 +94,11 @@ impl Default for StreamingMetrics {
 impl StreamingMetrics {
    /// Create a new streaming metrics calculator.
    pub fn new() -> Self {
+        Self::with_initial_capital(0.0)
+    }
+
+    /// Create a new streaming metrics calculator with initial capital.
+    pub fn with_initial_capital(initial_capital: f64) -> Self {
        Self {
            count: 0,
            mean: 0.0,
@@ -49,6 +110,32 @@ impl StreamingMetrics {
            sum_negative: 0.0,
            count_positive: 0,
            count_negative: 0,
+            // Equity tracking
+            initial_capital,
+            peak_equity: initial_capital,
+            current_equity: initial_capital,
+            max_drawdown_pct: 0.0,
+            current_drawdown: 0.0,
+            bars_since_peak: 0,
+            max_drawdown_duration: 0,
+            // Trade tracking
+            trade_count: 0,
+            winning_trades: 0,
+            losing_trades: 0,
+            sum_wins: 0.0,
+            sum_losses: 0.0,
+            sum_trade_returns: 0.0,
+            sum_trade_returns_sq: 0.0,
+            best_trade_pct: f64::NEG_INFINITY,
+            worst_trade_pct: f64::INFINITY,
+            sum_winning_duration: 0,
+            sum_losing_duration: 0,
+            current_consecutive_wins: 0,
+            current_consecutive_losses: 0,
+            max_consecutive_wins: 0,
+            max_consecutive_losses: 0,
+            total_holding_period: 0,
+            total_fees: 0.0,
        }
    }

@@ -218,6 +305,249 @@ impl StreamingMetrics {
        self.profit_factor()
    }

+    // === Equity tracking methods ===
+
+    /// Update equity and calculate drawdown.
+    pub fn update_equity(&mut self, equity: f64) {
+        self.current_equity = equity;
+
+        if equity > self.peak_equity {
+            self.peak_equity = equity;
+            self.bars_since_peak = 0;
+        } else {
+            self.bars_since_peak += 1;
+            if self.bars_since_peak > self.max_drawdown_duration {
+                self.max_drawdown_duration = self.bars_since_peak;
+            }
+        }
+
+        // Calculate current drawdown percentage
+        if self.peak_equity > 0.0 {
+            self.current_drawdown = (self.peak_equity - equity) / self.peak_equity * 100.0;
+            if self.current_drawdown > self.max_drawdown_pct {
+                self.max_drawdown_pct = self.current_drawdown;
+            }
+        }
+    }
+
+    /// Get current drawdown percentage.
+    #[inline]
+    pub fn current_drawdown_pct(&self) -> f64 {
+        self.current_drawdown
+    }
+
+    /// Get maximum drawdown percentage.
+    #[inline]
+    pub fn max_drawdown_pct(&self) -> f64 {
+        self.max_drawdown_pct
+    }
+
+    // === Trade tracking methods ===
+
+    /// Record a completed trade.
+    ///
+    /// # Arguments
+    /// * `pnl` - Trade profit/loss
+    /// * `return_pct` - Trade return percentage
+    /// * `duration` - Trade duration in bars
+    pub fn record_trade(&mut self, pnl: f64, return_pct: f64, duration: usize) {
+        self.trade_count += 1;
+        self.sum_trade_returns += return_pct;
+        self.sum_trade_returns_sq += return_pct * return_pct;
+        self.total_holding_period += duration;
+
+        // Track best/worst trades
+        if return_pct > self.best_trade_pct {
+            self.best_trade_pct = return_pct;
+        }
+        if return_pct < self.worst_trade_pct {
+            self.worst_trade_pct = return_pct;
+        }
+
+        if pnl > 0.0 {
+            self.winning_trades += 1;
+            self.sum_wins += pnl;
+            self.sum_winning_duration += duration;
+            self.current_consecutive_wins += 1;
+            self.current_consecutive_losses = 0;
+            if self.current_consecutive_wins > self.max_consecutive_wins {
+                self.max_consecutive_wins = self.current_consecutive_wins;
+            }
+        } else if pnl < 0.0 {
+            self.losing_trades += 1;
+            self.sum_losses += pnl.abs();
+            self.sum_losing_duration += duration;
+            self.current_consecutive_losses += 1;
+            self.current_consecutive_wins = 0;
+            if self.current_consecutive_losses > self.max_consecutive_losses {
+                self.max_consecutive_losses = self.current_consecutive_losses;
+            }
+        }
+    }
+
+    /// Record fees paid.
+    pub fn record_fees(&mut self, fees: f64) {
+        self.total_fees += fees;
+    }
+
+    /// Finalize metrics and produce BacktestMetrics.
+    ///
+    /// # Arguments
+    /// * `initial_capital` - Starting capital
+    /// * `final_value` - Ending portfolio value
+    /// * `returns` - Array of period returns for ratio calculations
+    pub fn finalize(
+        &self,
+        initial_capital: f64,
+        final_value: f64,
+        returns: &[f64],
+    ) -> BacktestMetrics {
+        // Calculate return metrics from the returns array
+        let mut return_metrics = StreamingMetrics::new();
+        for &r in returns {
+            if !r.is_nan() {
+                return_metrics.update(r);
+            }
+        }
+
+        let total_return_pct = if initial_capital > 0.0 {
+            (final_value - initial_capital) / initial_capital * 100.0
+        } else {
+            0.0
+        };
+
+        // Calculate trade-based metrics
+        let win_rate_pct = if self.trade_count > 0 {
+            self.winning_trades as f64 / self.trade_count as f64 * 100.0
+        } else {
+            0.0
+        };
+
+        let profit_factor = if self.sum_losses > 0.0 {
+            self.sum_wins / self.sum_losses
+        } else if self.sum_wins > 0.0 {
+            f64::INFINITY
+        } else {
+            0.0
+        };
+
+        let avg_trade_return_pct = if self.trade_count > 0 {
+            self.sum_trade_returns / self.trade_count as f64
+        } else {
+            0.0
+        };
+
+        let avg_win_pct = if self.winning_trades > 0 {
+            self.sum_wins / self.winning_trades as f64 / initial_capital * 100.0
+        } else {
+            0.0
+        };
+
+        let avg_loss_pct = if self.losing_trades > 0 {
+            -(self.sum_losses / self.losing_trades as f64 / initial_capital * 100.0)
+        } else {
+            0.0
+        };
+
+        let avg_winning_duration = if self.winning_trades > 0 {
+            self.sum_winning_duration as f64 / self.winning_trades as f64
+        } else {
+            0.0
+        };
+
+        let avg_losing_duration = if self.losing_trades > 0 {
+            self.sum_losing_duration as f64 / self.losing_trades as f64
+        } else {
+            0.0
+        };
+
+        let avg_holding_period = if self.trade_count > 0 {
+            self.total_holding_period as f64 / self.trade_count as f64
+        } else {
+            0.0
+        };
+
+        // Expectancy: average profit per trade
+        let expectancy = if self.trade_count > 0 {
+            (self.sum_wins - self.sum_losses) / self.trade_count as f64
+        } else {
+            0.0
+        };
+
+        // SQN (System Quality Number)
+        let sqn = if self.trade_count > 1 {
+            let mean_return = self.sum_trade_returns / self.trade_count as f64;
+            let variance =
+                (self.sum_trade_returns_sq / self.trade_count as f64) - (mean_return * mean_return);
+            let std_dev = variance.max(0.0).sqrt();
+            if std_dev > 0.0 {
+                (mean_return / std_dev) * (self.trade_count as f64).sqrt()
+            } else {
+                0.0
+            }
+        } else {
+            0.0
+        };
+
+        // Sharpe ratio (annualized, assuming 252 trading days)
+        let sharpe_ratio = return_metrics.sharpe_ratio(252.0);
+
+        // Sortino ratio (annualized)
+        let sortino_ratio = return_metrics.sortino_ratio(252.0);
+
+        // Calmar ratio (annualized return / max drawdown)
+        let calmar_ratio = if self.max_drawdown_pct > 0.0 {
+            total_return_pct / self.max_drawdown_pct
+        } else if total_return_pct > 0.0 {
+            f64::INFINITY
+        } else {
+            0.0
+        };
+
+        // Omega ratio
+        let omega_ratio = return_metrics.omega_ratio();
+
+        // Best/worst trade handling (handle edge cases)
+        let best_trade_pct =
+            if self.best_trade_pct == f64::NEG_INFINITY { 0.0 } else { self.best_trade_pct };
+        let worst_trade_pct =
+            if self.worst_trade_pct == f64::INFINITY { 0.0 } else { self.worst_trade_pct };
+
+        BacktestMetrics {
+            total_return_pct,
+            sharpe_ratio,
+            sortino_ratio,
+            calmar_ratio,
+            omega_ratio,
+            max_drawdown_pct: self.max_drawdown_pct,
+            max_drawdown_duration: self.max_drawdown_duration,
+            win_rate_pct,
+            profit_factor,
+            expectancy,
+            sqn,
+            total_trades: self.trade_count,
+            total_closed_trades: self.trade_count,
+            total_open_trades: 0,
+            open_trade_pnl: 0.0,
+            winning_trades: self.winning_trades,
+            losing_trades: self.losing_trades,
+            start_value: initial_capital,
+            end_value: final_value,
+            total_fees_paid: self.total_fees,
+            best_trade_pct,
+            worst_trade_pct,
+            avg_trade_return_pct,
+            avg_win_pct,
+            avg_loss_pct,
+            avg_winning_duration,
+            avg_losing_duration,
+            max_consecutive_wins: self.max_consecutive_wins,
+            max_consecutive_losses: self.max_consecutive_losses,
+            avg_holding_period,
+            exposure_pct: 0.0, // TODO: calculate based on time in market
+        }
+    }
+
    /// Reset all metrics.
    pub fn reset(&mut self) {
        *self = Self::new();
@@ -2,7 +2,7 @@

 use crate::core::types::{
    BacktestConfig, BacktestMetrics, BacktestResult, CompiledSignals, Direction, ExitReason,
-    OhlcvData, Price, StopConfig, TargetConfig, Trade,
+    InstrumentConfig, OhlcvData, Price, StopConfig, TargetConfig, Trade,
 };
 use crate::execution::{FeeModel, FillPrice, SlippageModel};
 use crate::indicators::volatility::atr;
@@ -69,6 +69,24 @@ impl PortfolioEngine {
    /// # Returns
    /// Backtest result
    pub fn run_single(&self, ohlcv: &OhlcvData, signals: &CompiledSignals) -> BacktestResult {
+        self.run_single_with_instrument_config(ohlcv, signals, None)
+    }
+
+    /// Run backtest on single instrument with optional per-instrument configuration.
+    ///
+    /// # Arguments
+    /// * `ohlcv` - OHLCV data
+    /// * `signals` - Compiled trading signals
+    /// * `inst_config` - Optional per-instrument config (lot_size, capital cap, stop/target overrides)
+    ///
+    /// # Returns
+    /// Backtest result
+    pub fn run_single_with_instrument_config(
+        &self,
+        ohlcv: &OhlcvData,
+        signals: &CompiledSignals,
+        inst_config: Option<&InstrumentConfig>,
+    ) -> BacktestResult {
        let n = ohlcv.len();
        assert_eq!(n, signals.len(), "OHLCV and signals must have same length");

@@ -86,14 +104,20 @@ impl PortfolioEngine {
        let mut streaming = StreamingMetrics::new();
        let mut peak_equity = cash;

+        // Determine effective stop/target configs (per-instrument overrides take precedence)
+        let effective_stop =
+            inst_config.and_then(|ic| ic.stop.as_ref()).unwrap_or(&self.config.stop);
+        let effective_target =
+            inst_config.and_then(|ic| ic.target.as_ref()).unwrap_or(&self.config.target);
+
        // Pre-calculate ATR for ATR-based stops
-        let atr_values = if matches!(self.config.stop, StopConfig::Atr { .. })
-            || matches!(self.config.target, TargetConfig::Atr { .. })
+        let atr_values = if matches!(effective_stop, StopConfig::Atr { .. })
+            || matches!(effective_target, TargetConfig::Atr { .. })
        {
-            let period = match self.config.stop {
-                StopConfig::Atr { period, .. } => period,
-                _ => match self.config.target {
-                    TargetConfig::Atr { period, .. } => period,
+            let period = match effective_stop {
+                StopConfig::Atr { period, .. } => *period,
+                _ => match effective_target {
+                    TargetConfig::Atr { period, .. } => *period,
                    _ => 14,
                },
            };
@@ -188,8 +212,8 @@ impl PortfolioEngine {

                // Update trailing stop if position still open
                if position.is_in_position() {
-                    if let StopConfig::Trailing { percent } = self.config.stop {
-                        position.update_trailing_stop(percent);
+                    if let StopConfig::Trailing { percent } = effective_stop {
+                        position.update_trailing_stop(*percent);
                    }
                }
            }
@@ -207,26 +231,37 @@ impl PortfolioEngine {
                );

                // Calculate position size
+                // Use per-instrument capital if set, capped at available cash
+                let available = inst_config
+                    .and_then(|ic| ic.alloted_capital)
+                    .map(|cap| cap.min(cash))
+                    .unwrap_or(cash);
+
                // VectorBT formula: size = cash / (price * (1 + fees))
                // This ensures the position value plus entry fee equals available cash
                let fee_rate = self.config.fees;
-                let size = if let Some(ref sizes) = signals.position_sizes {
-                    sizes[i] * cash / (adjusted_price * (1.0 + fee_rate))
+                let raw_size = if let Some(ref sizes) = signals.position_sizes {
+                    sizes[i] * available / (adjusted_price * (1.0 + fee_rate))
                } else {
-                    cash / (adjusted_price * (1.0 + fee_rate))
+                    available / (adjusted_price * (1.0 + fee_rate))
                };

+                // Round to lot_size
+                let size = inst_config.map(|ic| ic.round_to_lot(raw_size)).unwrap_or(raw_size);
+
                if size > 0.0 {
                    // Calculate entry fees
                    let entry_fees =
                        self.fee_model.calculate(adjusted_price, size, signals.direction);

                    // Calculate stop and target prices
-                    let (stop_price, target_price) = self.calculate_stop_target(
+                    let (stop_price, target_price) = self.calculate_stop_target_with_config(
                        adjusted_price,
                        signals.direction,
                        &atr_values,
                        i,
+                        effective_stop,
+                        effective_target,
                    );

                    // Open position (passing entry_fees for trade PnL tracking)
@@ -310,18 +345,39 @@ impl PortfolioEngine {
        )
    }

-    /// Calculate stop and target prices.
+    /// Calculate stop and target prices using the global config.
+    #[allow(dead_code)]
    fn calculate_stop_target(
        &self,
        entry_price: Price,
        direction: Direction,
        atr_values: &[f64],
        idx: usize,
+    ) -> (Option<Price>, Option<Price>) {
+        self.calculate_stop_target_with_config(
+            entry_price,
+            direction,
+            atr_values,
+            idx,
+            &self.config.stop,
+            &self.config.target,
+        )
+    }
+
+    /// Calculate stop and target prices with explicit stop/target configs.
+    fn calculate_stop_target_with_config(
+        &self,
+        entry_price: Price,
+        direction: Direction,
+        atr_values: &[f64],
+        idx: usize,
+        stop_config: &StopConfig,
+        target_config: &TargetConfig,
    ) -> (Option<Price>, Option<Price>) {
        let multiplier = direction.multiplier();

        // Calculate stop price
-        let stop_price = match self.config.stop {
+        let stop_price = match stop_config {
            StopConfig::None => None,
            StopConfig::Fixed { percent } => Some(entry_price * (1.0 - multiplier * percent)),
            StopConfig::Atr { multiplier: m, .. } => {
@@ -336,7 +392,7 @@ impl PortfolioEngine {
        };

        // Calculate target price
-        let target_price = match self.config.target {
+        let target_price = match target_config {
            TargetConfig::None => None,
            TargetConfig::Fixed { percent } => Some(entry_price * (1.0 + multiplier * percent)),
            TargetConfig::Atr { multiplier: m, .. } => {
@@ -2,8 +2,10 @@

 pub mod allocation;
 pub mod engine;
+pub mod monte_carlo;
 pub mod position;

 pub use allocation::{AllocationStrategy, CapitalAllocator};
 pub use engine::PortfolioEngine;
+pub use monte_carlo::{simulate_portfolio_forward, MonteCarloConfig, MonteCarloResult};
 pub use position::PositionManager;
@@ -0,0 +1,361 @@
+//! Monte Carlo forward simulation for portfolio projection.
+//!
+//! Uses Geometric Brownian Motion (GBM) with Cholesky decomposition
+//! for correlated multi-asset simulation. Parallelized via Rayon.
+
+use rayon::prelude::*;
+
+/// Configuration for Monte Carlo simulation.
+#[derive(Debug, Clone)]
+pub struct MonteCarloConfig {
+    pub n_simulations: usize,
+    pub horizon_days: usize,
+    pub seed: u64,
+}
+
+impl Default for MonteCarloConfig {
+    fn default() -> Self {
+        Self { n_simulations: 10_000, horizon_days: 252, seed: 42 }
+    }
+}
+
+/// Result of a Monte Carlo simulation.
+#[derive(Debug, Clone)]
+pub struct MonteCarloResult {
+    /// Percentile paths: Vec of (percentile, path_values)
+    pub percentile_paths: Vec<(f64, Vec<f64>)>,
+    /// Terminal value for each simulation
+    pub final_values: Vec<f64>,
+    /// Expected annualized return
+    pub expected_return: f64,
+    /// Probability of loss (final value < initial value)
+    pub probability_of_loss: f64,
+    /// Value at Risk at 95% confidence
+    pub var_95: f64,
+    /// Conditional Value at Risk at 95% confidence
+    pub cvar_95: f64,
+}
+
+/// Cholesky decomposition of a symmetric positive-definite matrix.
+/// Returns lower-triangular matrix L such that A = L * L^T.
+fn cholesky(matrix: &[Vec<f64>]) -> Result<Vec<Vec<f64>>, &'static str> {
+    let n = matrix.len();
+    let mut l = vec![vec![0.0; n]; n];
+
+    for i in 0..n {
+        for j in 0..=i {
+            let mut sum = 0.0;
+            for k in 0..j {
+                sum += l[i][k] * l[j][k];
+            }
+
+            if i == j {
+                let diag = matrix[i][i] - sum;
+                if diag <= 0.0 {
+                    // Matrix is not positive definite; use a small epsilon
+                    l[i][j] = (diag.abs().max(1e-10)).sqrt();
+                } else {
+                    l[i][j] = diag.sqrt();
+                }
+            } else {
+                if l[j][j].abs() < 1e-15 {
+                    l[i][j] = 0.0;
+                } else {
+                    l[i][j] = (matrix[i][j] - sum) / l[j][j];
+                }
+            }
+        }
+    }
+
+    Ok(l)
+}
+
+/// Simple xoshiro256** PRNG for deterministic parallel simulation.
+#[derive(Clone)]
+struct Xoshiro256 {
+    s: [u64; 4],
+}
+
+impl Xoshiro256 {
+    fn new(seed: u64) -> Self {
+        // SplitMix64 to seed all 4 state words
+        let mut z = seed;
+        let mut s = [0u64; 4];
+        for item in &mut s {
+            z = z.wrapping_add(0x9e3779b97f4a7c15);
+            z = (z ^ (z >> 30)).wrapping_mul(0xbf58476d1ce4e5b9);
+            z = (z ^ (z >> 27)).wrapping_mul(0x94d049bb133111eb);
+            *item = z ^ (z >> 31);
+        }
+        Self { s }
+    }
+
+    fn jump(&mut self) {
+        // Jump function: advances state by 2^128 calls
+        const JUMP: [u64; 4] =
+            [0x180ec6d33cfd0aba, 0xd5a61266f0c9392c, 0xa9582618e03fc9aa, 0x39abdc4529b1661c];
+        let mut s0: u64 = 0;
+        let mut s1: u64 = 0;
+        let mut s2: u64 = 0;
+        let mut s3: u64 = 0;
+        for j in &JUMP {
+            for b in 0..64 {
+                if j & (1u64 << b) != 0 {
+                    s0 ^= self.s[0];
+                    s1 ^= self.s[1];
+                    s2 ^= self.s[2];
+                    s3 ^= self.s[3];
+                }
+                self.next_u64();
+            }
+        }
+        self.s[0] = s0;
+        self.s[1] = s1;
+        self.s[2] = s2;
+        self.s[3] = s3;
+    }
+
+    fn next_u64(&mut self) -> u64 {
+        let result = (self.s[1].wrapping_mul(5)).rotate_left(7).wrapping_mul(9);
+        let t = self.s[1] << 17;
+        self.s[2] ^= self.s[0];
+        self.s[3] ^= self.s[1];
+        self.s[1] ^= self.s[2];
+        self.s[0] ^= self.s[3];
+        self.s[2] ^= t;
+        self.s[3] = self.s[3].rotate_left(45);
+        result
+    }
+
+    /// Generate uniform f64 in [0, 1).
+    fn next_f64(&mut self) -> f64 {
+        (self.next_u64() >> 11) as f64 * (1.0 / (1u64 << 53) as f64)
+    }
+
+    /// Box-Muller transform for standard normal.
+    fn next_normal(&mut self) -> f64 {
+        let u1 = self.next_f64().max(1e-15);
+        let u2 = self.next_f64();
+        (-2.0 * u1.ln()).sqrt() * (2.0 * std::f64::consts::PI * u2).cos()
+    }
+}
+
+/// Core Monte Carlo simulation function.
+///
+/// # Arguments
+/// * `returns` - Per-strategy daily returns (N strategies x T days each)
+/// * `weights` - Portfolio weights (length N, must sum to 1)
+/// * `correlation_matrix` - N x N correlation matrix
+/// * `initial_value` - Starting portfolio value
+/// * `config` - Simulation configuration
+pub fn simulate_portfolio_forward(
+    returns: &[Vec<f64>],
+    weights: &[f64],
+    correlation_matrix: &[Vec<f64>],
+    initial_value: f64,
+    config: &MonteCarloConfig,
+) -> MonteCarloResult {
+    let n_assets = returns.len();
+    let dt = 1.0; // daily time step
+
+    // Compute per-asset mean and std of historical returns
+    let mut mus = vec![0.0; n_assets];
+    let mut sigmas = vec![0.0; n_assets];
+    for (i, ret) in returns.iter().enumerate() {
+        if ret.is_empty() {
+            continue;
+        }
+        let mean = ret.iter().sum::<f64>() / ret.len() as f64;
+        let var = ret.iter().map(|r| (r - mean).powi(2)).sum::<f64>() / ret.len() as f64;
+        mus[i] = mean;
+        sigmas[i] = var.sqrt().max(1e-10);
+    }
+
+    // Cholesky decomposition of correlation matrix
+    let chol = cholesky(correlation_matrix).unwrap_or_else(|_| {
+        // Fallback: identity matrix (independent assets)
+        let mut identity = vec![vec![0.0; n_assets]; n_assets];
+        for i in 0..n_assets {
+            identity[i][i] = 1.0;
+        }
+        identity
+    });
+
+    // Prepare a base RNG and create per-chunk seeds via jumping
+    let mut base_rng = Xoshiro256::new(config.seed);
+    let n_chunks = rayon::current_num_threads().max(1);
+    let chunk_size = (config.n_simulations + n_chunks - 1) / n_chunks;
+
+    let chunk_rngs: Vec<Xoshiro256> = (0..n_chunks)
+        .map(|_| {
+            let rng = base_rng.clone();
+            base_rng.jump();
+            rng
+        })
+        .collect();
+
+    // Run simulations in parallel chunks
+    let all_paths: Vec<Vec<f64>> = chunk_rngs
+        .into_par_iter()
+        .enumerate()
+        .flat_map(|(chunk_idx, mut rng)| {
+            let start = chunk_idx * chunk_size;
+            let end = (start + chunk_size).min(config.n_simulations);
+            let mut chunk_paths = Vec::with_capacity(end - start);
+
+            for _ in start..end {
+                let mut portfolio_value = initial_value;
+                let mut path = Vec::with_capacity(config.horizon_days + 1);
+                path.push(portfolio_value);
+
+                for _ in 0..config.horizon_days {
+                    // Generate N independent standard normals
+                    let z_indep: Vec<f64> = (0..n_assets).map(|_| rng.next_normal()).collect();
+
+                    // Correlate via Cholesky: z_corr = L * z_indep
+                    let mut z_corr = vec![0.0; n_assets];
+                    for i in 0..n_assets {
+                        for j in 0..=i {
+                            z_corr[i] += chol[i][j] * z_indep[j];
+                        }
+                    }
+
+                    // GBM per asset, then weighted portfolio return
+                    let mut portfolio_return = 0.0;
+                    for i in 0..n_assets {
+                        let drift = (mus[i] - 0.5 * sigmas[i].powi(2)) * dt;
+                        let diffusion = sigmas[i] * dt.sqrt() * z_corr[i];
+                        let asset_return = (drift + diffusion).exp() - 1.0;
+                        portfolio_return += weights[i] * asset_return;
+                    }
+
+                    portfolio_value *= 1.0 + portfolio_return;
+                    path.push(portfolio_value);
+                }
+
+                chunk_paths.push(path);
+            }
+
+            chunk_paths
+        })
+        .collect();
+
+    // Extract final values
+    let mut final_values: Vec<f64> = all_paths.iter().map(|p| *p.last().unwrap()).collect();
+    final_values.sort_by(|a, b| a.partial_cmp(b).unwrap_or(std::cmp::Ordering::Equal));
+
+    let n = final_values.len();
+
+    // Percentile paths: find simulations closest to each percentile's final value
+    let percentiles = [5.0, 25.0, 50.0, 75.0, 95.0];
+    let percentile_paths: Vec<(f64, Vec<f64>)> = percentiles
+        .iter()
+        .map(|&pct| {
+            let idx = ((pct / 100.0) * (n as f64 - 1.0)).round() as usize;
+            let target_final = final_values[idx.min(n - 1)];
+
+            // Find the simulation path whose final value is closest to target
+            let best_idx = all_paths
+                .iter()
+                .enumerate()
+                .min_by(|(_, a), (_, b)| {
+                    let da = (a.last().unwrap() - target_final).abs();
+                    let db = (b.last().unwrap() - target_final).abs();
+                    da.partial_cmp(&db).unwrap_or(std::cmp::Ordering::Equal)
+                })
+                .map(|(i, _)| i)
+                .unwrap_or(0);
+
+            (pct, all_paths[best_idx].clone())
+        })
+        .collect();
+
+    // Expected return (annualized from mean of final values)
+    let mean_final = final_values.iter().sum::<f64>() / n as f64;
+    let expected_return = (mean_final / initial_value - 1.0) * 100.0;
+
+    // Probability of loss
+    let n_loss = final_values.iter().filter(|&&v| v < initial_value).count();
+    let probability_of_loss = n_loss as f64 / n as f64;
+
+    // VaR 95%: 5th percentile loss
+    let p5_idx = ((0.05 * (n as f64 - 1.0)).round() as usize).min(n - 1);
+    let var_95 = ((initial_value - final_values[p5_idx]) / initial_value * 100.0).max(0.0);
+
+    // CVaR 95%: average of losses below VaR
+    let cvar_values = &final_values[..=p5_idx];
+    let cvar_95 = if cvar_values.is_empty() {
+        var_95
+    } else {
+        let avg_tail = cvar_values.iter().sum::<f64>() / cvar_values.len() as f64;
+        ((initial_value - avg_tail) / initial_value * 100.0).max(0.0)
+    };
+
+    MonteCarloResult {
+        percentile_paths,
+        final_values,
+        expected_return,
+        probability_of_loss,
+        var_95,
+        cvar_95,
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_cholesky_identity() {
+        let matrix = vec![vec![1.0, 0.0], vec![0.0, 1.0]];
+        let l = cholesky(&matrix).unwrap();
+        assert!((l[0][0] - 1.0).abs() < 1e-10);
+        assert!((l[1][1] - 1.0).abs() < 1e-10);
+        assert!(l[0][1].abs() < 1e-10);
+        assert!(l[1][0].abs() < 1e-10);
+    }
+
+    #[test]
+    fn test_cholesky_correlated() {
+        let matrix = vec![vec![1.0, 0.5], vec![0.5, 1.0]];
+        let l = cholesky(&matrix).unwrap();
+        // Verify L * L^T = matrix
+        let reconstructed_00 = l[0][0] * l[0][0];
+        let reconstructed_01 = l[1][0] * l[0][0];
+        let reconstructed_11 = l[1][0] * l[1][0] + l[1][1] * l[1][1];
+        assert!((reconstructed_00 - 1.0).abs() < 1e-10);
+        assert!((reconstructed_01 - 0.5).abs() < 1e-10);
+        assert!((reconstructed_11 - 1.0).abs() < 1e-10);
+    }
+
+    #[test]
+    fn test_simulate_basic() {
+        // Two assets with identical positive returns
+        let returns = vec![vec![0.001; 252], vec![0.001; 252]];
+        let weights = vec![0.5, 0.5];
+        let corr = vec![vec![1.0, 0.0], vec![0.0, 1.0]];
+        let config = MonteCarloConfig { n_simulations: 100, horizon_days: 10, seed: 42 };
+
+        let result = simulate_portfolio_forward(&returns, &weights, &corr, 100000.0, &config);
+
+        assert_eq!(result.final_values.len(), 100);
+        assert_eq!(result.percentile_paths.len(), 5);
+        // Expected return should be positive given positive drift
+        assert!(result.expected_return > -50.0); // Sanity check
+    }
+
+    #[test]
+    fn test_deterministic() {
+        let returns = vec![vec![0.001; 100], vec![-0.0005; 100]];
+        let weights = vec![0.6, 0.4];
+        let corr = vec![vec![1.0, -0.3], vec![-0.3, 1.0]];
+        let config = MonteCarloConfig { n_simulations: 50, horizon_days: 20, seed: 123 };
+
+        let r1 = simulate_portfolio_forward(&returns, &weights, &corr, 100000.0, &config);
+        let r2 = simulate_portfolio_forward(&returns, &weights, &corr, 100000.0, &config);
+
+        // Same seed should produce same final values (single-threaded determinism)
+        // Note: with rayon, parallelism may affect order but not values
+        assert!((r1.expected_return - r2.expected_return).abs() < 1e-6);
+    }
+}
@@ -3,8 +3,11 @@
 use numpy::{PyArray1, PyReadonlyArray1};
 use pyo3::prelude::*;

+use std::collections::HashMap;
+
 use crate::core::types::{
-    BacktestConfig, CompiledSignals, Direction, OhlcvData, StopConfig, TargetConfig,
+    BacktestConfig, CompiledSignals, Direction, InstrumentConfig, OhlcvData, StopConfig,
+    TargetConfig,
 };
 use crate::indicators;
 use crate::signals::synchronizer::SyncMode;
@@ -15,6 +18,9 @@ use crate::strategies::options::{
 };
 use crate::strategies::pairs::{PairsBacktest, PairsConfig};
 use crate::strategies::single::SingleBacktest;
+use crate::strategies::spreads::{
+    LegConfig, OptionType as SpreadOptionType, SpreadBacktest, SpreadConfig, SpreadType,
+};

 use super::numpy_bridge::*;

@@ -97,6 +103,93 @@ impl From<&PyBacktestConfig> for BacktestConfig {
    }
 }

+/// Python-exposed per-instrument configuration.
+#[pyclass]
+#[derive(Debug, Clone)]
+pub struct PyInstrumentConfig {
+    #[pyo3(get, set)]
+    pub lot_size: Option<f64>,
+    #[pyo3(get, set)]
+    pub alloted_capital: Option<f64>,
+    #[pyo3(get, set)]
+    pub existing_qty: Option<f64>,
+    #[pyo3(get, set)]
+    pub avg_price: Option<f64>,
+    stop_config: Option<StopConfig>,
+    target_config: Option<TargetConfig>,
+}
+
+#[pymethods]
+impl PyInstrumentConfig {
+    #[new]
+    #[pyo3(signature = (lot_size=None, alloted_capital=None, existing_qty=None, avg_price=None))]
+    fn new(
+        lot_size: Option<f64>,
+        alloted_capital: Option<f64>,
+        existing_qty: Option<f64>,
+        avg_price: Option<f64>,
+    ) -> Self {
+        Self {
+            lot_size,
+            alloted_capital,
+            existing_qty,
+            avg_price,
+            stop_config: None,
+            target_config: None,
+        }
+    }
+
+    /// Set fixed percentage stop-loss override.
+    fn set_fixed_stop(&mut self, percent: f64) {
+        self.stop_config = Some(StopConfig::Fixed { percent });
+    }
+
+    /// Set ATR-based stop-loss override.
+    fn set_atr_stop(&mut self, multiplier: f64, period: usize) {
+        self.stop_config = Some(StopConfig::Atr { multiplier, period });
+    }
+
+    /// Set trailing stop-loss override.
+    fn set_trailing_stop(&mut self, percent: f64) {
+        self.stop_config = Some(StopConfig::Trailing { percent });
+    }
+
+    /// Set fixed percentage take-profit override.
+    fn set_fixed_target(&mut self, percent: f64) {
+        self.target_config = Some(TargetConfig::Fixed { percent });
+    }
+
+    /// Set ATR-based take-profit override.
+    fn set_atr_target(&mut self, multiplier: f64, period: usize) {
+        self.target_config = Some(TargetConfig::Atr { multiplier, period });
+    }
+
+    /// Set risk-reward based take-profit override.
+    fn set_risk_reward_target(&mut self, ratio: f64) {
+        self.target_config = Some(TargetConfig::RiskReward { ratio });
+    }
+
+    fn __repr__(&self) -> String {
+        format!(
+            "InstrumentConfig(lot_size={:?}, alloted_capital={:?})",
+            self.lot_size, self.alloted_capital
+        )
+    }
+}
+
+impl From<&PyInstrumentConfig> for InstrumentConfig {
+    fn from(py_config: &PyInstrumentConfig) -> Self {
+        InstrumentConfig {
+            lot_size: py_config.lot_size,
+            alloted_capital: py_config.alloted_capital,
+            stop: py_config.stop_config,
+            target: py_config.target_config,
+            existing_qty: py_config.existing_qty,
+            avg_price: py_config.avg_price,
+        }
+    }
+}
+
 /// Python-exposed stop configuration.
 #[pyclass]
 #[derive(Debug, Clone)]
@@ -416,7 +509,7 @@ impl PyBacktestResult {

 /// Run single instrument backtest.
 #[pyfunction]
-#[pyo3(signature = (timestamps, open, high, low, close, volume, entries, exits, direction=1, weight=1.0, symbol="UNKNOWN", config=None, position_sizes=None))]
+#[pyo3(signature = (timestamps, open, high, low, close, volume, entries, exits, direction=1, weight=1.0, symbol="UNKNOWN", config=None, position_sizes=None, instrument_config=None))]
 pub fn run_single_backtest<'py>(
    _py: Python<'py>,
    timestamps: PyReadonlyArray1<i64>,
@@ -432,6 +525,7 @@ pub fn run_single_backtest<'py>(
    symbol: &str,
    config: Option<&PyBacktestConfig>,
    position_sizes: Option<PyReadonlyArray1<f64>>,
+    instrument_config: Option<&PyInstrumentConfig>,
 ) -> PyResult<PyBacktestResult> {
    let ohlcv = OhlcvData {
        timestamps: numpy_to_vec_i64(timestamps),
@@ -454,16 +548,17 @@ pub fn run_single_backtest<'py>(
    };

    let rust_config = config.map(|c| BacktestConfig::from(c)).unwrap_or_default();
+    let inst_config = instrument_config.map(InstrumentConfig::from);

    let backtest = SingleBacktest::new(rust_config);
-    let result = backtest.run(&ohlcv, &signals);
+    let result = backtest.run_with_instrument_config(&ohlcv, &signals, inst_config.as_ref());

    Ok(convert_result(result))
 }

 /// Run basket/collective backtest.
 #[pyfunction]
-#[pyo3(signature = (instruments, config=None, sync_mode="all"))]
+#[pyo3(signature = (instruments, config=None, sync_mode="all", instrument_configs=None))]
 pub fn run_basket_backtest<'py>(
    _py: Python<'py>,
    instruments: Vec<(
@@ -481,6 +576,7 @@ pub fn run_basket_backtest<'py>(
    )>,
    config: Option<&PyBacktestConfig>,
    sync_mode: &str,
+    instrument_configs: Option<HashMap<String, PyInstrumentConfig>>,
 ) -> PyResult<PyBacktestResult> {
    let rust_instruments: Vec<(OhlcvData, CompiledSignals)> = instruments
        .into_iter()
@@ -518,8 +614,15 @@ pub fn run_basket_backtest<'py>(
        ..Default::default()
    };

+    // Convert PyInstrumentConfig map to InstrumentConfig map
+    let rust_inst_configs: Option<HashMap<String, InstrumentConfig>> =
+        instrument_configs.map(|configs| {
+            configs.iter().map(|(k, v)| (k.clone(), InstrumentConfig::from(v))).collect()
+        });
+
    let backtest = BasketBacktest::new(basket_config);
-    let result = backtest.run(&rust_instruments);
+    let result =
+        backtest.run_with_instrument_configs(&rust_instruments, rust_inst_configs.as_ref());

    Ok(convert_result(result))
 }
@@ -673,6 +776,68 @@ pub fn run_pairs_backtest<'py>(
    Ok(convert_result(result))
 }

+/// Run spread backtest (multi-leg options).
+#[pyfunction]
+#[pyo3(signature = (timestamps, underlying_close, legs_premiums, leg_configs, entries, exits, config=None, spread_type="custom", max_loss=None, target_profit=None))]
+pub fn run_spread_backtest<'py>(
+    _py: Python<'py>,
+    timestamps: PyReadonlyArray1<i64>,
+    underlying_close: PyReadonlyArray1<f64>,
+    legs_premiums: Vec<PyReadonlyArray1<f64>>,
+    leg_configs: Vec<(String, f64, i32, usize)>, // (option_type, strike, quantity, lot_size)
+    entries: PyReadonlyArray1<bool>,
+    exits: PyReadonlyArray1<bool>,
+    config: Option<&PyBacktestConfig>,
+    spread_type: &str,
+    max_loss: Option<f64>,
+    target_profit: Option<f64>,
+) -> PyResult<PyBacktestResult> {
+    let ts = numpy_to_vec_i64(timestamps);
+    let underlying = numpy_to_vec_f64(underlying_close);
+    let premiums: Vec<Vec<f64>> = legs_premiums.into_iter().map(numpy_to_vec_f64).collect();
+    let entry_signals = numpy_to_vec_bool(entries);
+    let exit_signals = numpy_to_vec_bool(exits);
+
+    // Convert leg configs
+    let rust_leg_configs: Vec<LegConfig> = leg_configs
+        .into_iter()
+        .map(|(opt_type, strike, quantity, lot_size)| {
+            let option_type =
+                SpreadOptionType::from_str(&opt_type).unwrap_or(SpreadOptionType::Call);
+            LegConfig::new(option_type, strike, quantity, lot_size)
+        })
+        .collect();
+
+    // Parse spread type
+    let spread_type_enum = match spread_type.to_lowercase().as_str() {
+        "straddle" => SpreadType::Straddle,
+        "strangle" => SpreadType::Strangle,
+        "vertical_call" | "verticalcall" => SpreadType::VerticalCall,
+        "vertical_put" | "verticalput" => SpreadType::VerticalPut,
+        "iron_condor" | "ironcondor" => SpreadType::IronCondor,
+        "iron_butterfly" | "ironbutterfly" => SpreadType::IronButterfly,
+        "butterfly_call" | "butterflycall" => SpreadType::ButterflyCall,
+        "butterfly_put" | "butterflyput" => SpreadType::ButterflyPut,
+        "calendar" => SpreadType::Calendar,
+        "diagonal" => SpreadType::Diagonal,
+        _ => SpreadType::Custom,
+    };
+
+    let spread_config = SpreadConfig {
+        base: config.map(|c| BacktestConfig::from(c)).unwrap_or_default(),
+        spread_type: spread_type_enum,
+        leg_configs: rust_leg_configs,
+        max_loss,
+        target_profit,
+        close_at_eod: false,
+    };
+
+    let backtest = SpreadBacktest::new(spread_config);
+    let result = backtest.run(&ts, &underlying, &premiums, &entry_signals, &exit_signals);
+
+    Ok(convert_result(result))
+}
+
 /// Run multi-strategy backtest.
 #[pyfunction]
 #[pyo3(signature = (timestamps, open, high, low, close, volume, strategies, config=None, combine_mode="any"))]
@@ -903,10 +1068,107 @@ pub fn supertrend<'py>(
    Ok((vec_to_numpy_f64(py, result.supertrend), direction_array))
 }

+/// Rolling minimum (Lowest Low Value).
+#[pyfunction]
+pub fn rolling_min<'py>(
+    py: Python<'py>,
+    data: PyReadonlyArray1<f64>,
+    period: usize,
+) -> PyResult<&'py PyArray1<f64>> {
+    let vec = numpy_to_vec_f64(data);
+    let result = indicators::rolling::rolling_min(&vec, period)
+        .map_err(|e| pyo3::exceptions::PyValueError::new_err(e.to_string()))?;
+    Ok(vec_to_numpy_f64(py, result))
+}
+
+/// Rolling maximum (Highest High Value).
+#[pyfunction]
+pub fn rolling_max<'py>(
+    py: Python<'py>,
+    data: PyReadonlyArray1<f64>,
+    period: usize,
+) -> PyResult<&'py PyArray1<f64>> {
+    let vec = numpy_to_vec_f64(data);
+    let result = indicators::rolling::rolling_max(&vec, period)
+        .map_err(|e| pyo3::exceptions::PyValueError::new_err(e.to_string()))?;
+    Ok(vec_to_numpy_f64(py, result))
+}
+
 // ============================================================================
 // Helper Functions
 // ============================================================================

+// ============================================================================
+// Monte Carlo Forward Simulation
+// ============================================================================
+
+/// Run Monte Carlo forward simulation for a portfolio.
+///
+/// Uses Geometric Brownian Motion with Cholesky-decomposed correlated random
+/// draws, parallelized via Rayon.
+///
+/// # Arguments
+/// * `returns` - List of per-strategy return arrays (N strategies)
+/// * `weights` - Portfolio weight vector (length N, sums to 1)
+/// * `correlation_matrix` - N x N correlation matrix (flattened row-major as 2D list)
+/// * `initial_value` - Starting portfolio value
+/// * `n_simulations` - Number of simulation paths (default: 10000)
+/// * `horizon_days` - Forward simulation horizon in trading days (default: 252)
+/// * `seed` - Random seed for reproducibility (default: 42)
+#[pyfunction]
+#[pyo3(signature = (returns, weights, correlation_matrix, initial_value, n_simulations=10000, horizon_days=252, seed=42))]
+pub fn simulate_portfolio_mc(
+    py: Python<'_>,
+    returns: Vec<PyReadonlyArray1<'_, f64>>,
+    weights: PyReadonlyArray1<'_, f64>,
+    correlation_matrix: Vec<PyReadonlyArray1<'_, f64>>,
+    initial_value: f64,
+    n_simulations: usize,
+    horizon_days: usize,
+    seed: u64,
+) -> PyResult<PyObject> {
+    use crate::portfolio::monte_carlo::{simulate_portfolio_forward, MonteCarloConfig};
+
+    // Convert numpy arrays to Rust vecs
+    let rust_returns: Vec<Vec<f64>> =
+        returns.iter().map(|arr| arr.as_slice().unwrap().to_vec()).collect();
+
+    let rust_weights: Vec<f64> = weights.as_slice().unwrap().to_vec();
+
+    let rust_corr: Vec<Vec<f64>> =
+        correlation_matrix.iter().map(|arr| arr.as_slice().unwrap().to_vec()).collect();
+
+    let config = MonteCarloConfig { n_simulations, horizon_days, seed };
+
+    // Run simulation (releases GIL for Rayon parallelism)
+    let result = py.allow_threads(|| {
+        simulate_portfolio_forward(&rust_returns, &rust_weights, &rust_corr, initial_value, &config)
+    });
+
+    // Build Python dict result
+    let dict = pyo3::types::PyDict::new(py);
+
+    // percentile_paths: list of (percentile, list[float])
+    let paths_list = pyo3::types::PyList::empty(py);
+    for (pct, path) in &result.percentile_paths {
+        let path_list = pyo3::types::PyList::new(py, path);
+        let tuple = pyo3::types::PyTuple::new(py, &[pct.to_object(py), path_list.to_object(py)]);
+        paths_list.append(tuple)?;
+    }
+    dict.set_item("percentile_paths", paths_list)?;
+
+    // final_values as numpy array for efficiency
+    let final_arr = PyArray1::from_vec(py, result.final_values);
+    dict.set_item("final_values", final_arr)?;
+
+    dict.set_item("expected_return", result.expected_return)?;
+    dict.set_item("probability_of_loss", result.probability_of_loss)?;
+    dict.set_item("var_95", result.var_95)?;
+    dict.set_item("cvar_95", result.cvar_95)?;
+
+    Ok(dict.into())
+}
+
 /// Convert Rust BacktestResult to Python PyBacktestResult.
 fn convert_result(result: crate::core::types::BacktestResult) -> PyBacktestResult {
    let metrics = PyBacktestMetrics {
@@ -2,8 +2,11 @@
 //!
 //! Supports multiple instruments with synchronized signals.

+use std::collections::HashMap;
+
 use crate::core::types::{
-    BacktestConfig, BacktestMetrics, BacktestResult, CompiledSignals, ExitReason, OhlcvData, Trade,
+    BacktestConfig, BacktestMetrics, BacktestResult, CompiledSignals, ExitReason, InstrumentConfig,
+    OhlcvData, Trade,
 };
 use crate::execution::FeeModel;
 use crate::metrics::streaming::StreamingMetrics;
@@ -74,6 +77,22 @@ impl BasketBacktest {
    /// # Returns
    /// Combined backtest result
    pub fn run(&self, instruments: &[(OhlcvData, CompiledSignals)]) -> BacktestResult {
+        self.run_with_instrument_configs(instruments, None)
+    }
+
+    /// Run basket backtest with optional per-instrument configurations.
+    ///
+    /// # Arguments
+    /// * `instruments` - Vector of (OhlcvData, CompiledSignals) pairs for each instrument
+    /// * `instrument_configs` - Optional map of symbol -> InstrumentConfig
+    ///
+    /// # Returns
+    /// Combined backtest result
+    pub fn run_with_instrument_configs(
+        &self,
+        instruments: &[(OhlcvData, CompiledSignals)],
+        instrument_configs: Option<&HashMap<String, InstrumentConfig>>,
+    ) -> BacktestResult {
        if instruments.is_empty() {
            return self.empty_result();
        }
@@ -168,7 +187,15 @@ impl BasketBacktest {
                // Calculate position sizes
                let prices: Vec<f64> = instruments.iter().map(|(o, _)| o.close[i]).collect();
                let weights: Vec<f64> = instruments.iter().map(|(_, s)| s.weight).collect();
-                let sizes = self.calculate_sizes(&prices, &weights, cash);
+                let symbols: Vec<&str> =
+                    instruments.iter().map(|(_, s)| s.symbol.as_str()).collect();
+                let sizes = self.calculate_sizes_with_configs(
+                    &prices,
+                    &weights,
+                    cash,
+                    &symbols,
+                    instrument_configs,
+                );

                // Enter positions
                for (inst_idx, (ohlcv, signals)) in instruments.iter().enumerate() {
@@ -249,7 +276,21 @@ impl BasketBacktest {
    }

    /// Calculate position sizes for each instrument.
+    #[allow(dead_code)]
    fn calculate_sizes(&self, prices: &[f64], weights: &[f64], available_capital: f64) -> Vec<f64> {
+        let symbols: Vec<&str> = vec![""; prices.len()];
+        self.calculate_sizes_with_configs(prices, weights, available_capital, &symbols, None)
+    }
+
+    /// Calculate position sizes with optional per-instrument config (lot_size rounding, capital caps).
+    fn calculate_sizes_with_configs(
+        &self,
+        prices: &[f64],
+        weights: &[f64],
+        available_capital: f64,
+        symbols: &[&str],
+        instrument_configs: Option<&HashMap<String, InstrumentConfig>>,
+    ) -> Vec<f64> {
        let n = prices.len();
        let total_weight: f64 = weights.iter().sum();

@@ -260,12 +301,26 @@ impl BasketBacktest {
        prices
            .iter()
            .zip(weights.iter())
-            .map(|(&price, &weight)| {
+            .enumerate()
+            .map(|(idx, (&price, &weight))| {
                if price <= 0.0 {
                    return 0.0;
                }
-                let allocation = available_capital * (weight / total_weight);
-                allocation / price
+                let default_allocation = available_capital * (weight / total_weight);
+
+                // Use per-instrument alloted_capital if set, capped at default allocation
+                let inst_config = instrument_configs
+                    .and_then(|configs| symbols.get(idx).and_then(|sym| configs.get(*sym)));
+
+                let allocation = inst_config
+                    .and_then(|ic| ic.alloted_capital)
+                    .map(|cap| cap.min(default_allocation))
+                    .unwrap_or(default_allocation);
+
+                let raw_size = allocation / price;
+
+                // Round to lot_size
+                inst_config.map(|ic| ic.round_to_lot(raw_size)).unwrap_or(raw_size)
            })
            .collect()
    }
@@ -5,9 +5,13 @@ pub mod multi;
 pub mod options;
 pub mod pairs;
 pub mod single;
+pub mod spreads;

 pub use basket::BasketBacktest;
 pub use multi::MultiStrategyBacktest;
 pub use options::OptionsBacktest;
 pub use pairs::PairsBacktest;
 pub use single::SingleBacktest;
+pub use spreads::{
+    LegConfig, OptionType as SpreadOptionType, SpreadBacktest, SpreadConfig, SpreadType,
+};
@@ -1,6 +1,8 @@
 //! Single instrument backtest implementation.

-use crate::core::types::{BacktestConfig, BacktestResult, CompiledSignals, OhlcvData};
+use crate::core::types::{
+    BacktestConfig, BacktestResult, CompiledSignals, InstrumentConfig, OhlcvData,
+};
 use crate::portfolio::engine::PortfolioEngine;

 /// Single instrument backtest runner.
@@ -28,6 +30,24 @@ impl SingleBacktest {
        self.engine.run_single(ohlcv, signals)
    }

+    /// Run the backtest with per-instrument configuration.
+    ///
+    /// # Arguments
+    /// * `ohlcv` - OHLCV price data
+    /// * `signals` - Compiled trading signals
+    /// * `inst_config` - Optional per-instrument config (lot_size, capital cap, stop/target overrides)
+    ///
+    /// # Returns
+    /// Backtest result with metrics, trades, and equity curve
+    pub fn run_with_instrument_config(
+        &self,
+        ohlcv: &OhlcvData,
+        signals: &CompiledSignals,
+        inst_config: Option<&InstrumentConfig>,
+    ) -> BacktestResult {
+        self.engine.run_single_with_instrument_config(ohlcv, signals, inst_config)
+    }
+
    /// Run backtest from raw arrays.
    ///
    /// # Arguments
@@ -0,0 +1,585 @@
+//! Multi-leg options spread backtesting implementation.
+//!
+//! Provides high-performance spread backtesting for:
+//! - Straddles and Strangles
+//! - Vertical spreads (bull/bear call/put)
+//! - Iron Condors and Iron Butterflies
+//! - Calendar and Diagonal spreads
+//!
+//! Key features:
+//! - Single-pass O(n) algorithm
+//! - Coordinated entry/exit across all legs
+//! - Net premium P&L calculation
+//! - Combined Greeks tracking
+
+use crate::core::types::{
+    BacktestConfig, BacktestMetrics, BacktestResult, Direction, ExitReason, Trade,
+};
+use crate::metrics::streaming::StreamingMetrics;
+use serde::{Deserialize, Serialize};
+
+/// Spread type enumeration.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
+pub enum SpreadType {
+    Straddle,
+    Strangle,
+    VerticalCall,
+    VerticalPut,
+    IronCondor,
+    IronButterfly,
+    ButterflyCall,
+    ButterflyPut,
+    Calendar,
+    Diagonal,
+    Custom,
+}
+
+/// Option type for a leg.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
+pub enum OptionType {
+    Call,
+    Put,
+}
+
+impl OptionType {
+    pub fn from_str(s: &str) -> Option<Self> {
+        match s.to_uppercase().as_str() {
+            "CE" | "CALL" | "C" => Some(OptionType::Call),
+            "PE" | "PUT" | "P" => Some(OptionType::Put),
+            _ => None,
+        }
+    }
+}
+
+/// Configuration for a single leg of a spread.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct LegConfig {
+    /// Option type (Call or Put).
+    pub option_type: OptionType,
+    /// Strike price.
+    pub strike: f64,
+    /// Position quantity (+1 long, -1 short).
+    pub quantity: i32,
+    /// Lot size for the option.
+    pub lot_size: usize,
+}
+
+impl LegConfig {
+    pub fn new(option_type: OptionType, strike: f64, quantity: i32, lot_size: usize) -> Self {
+        Self { option_type, strike, quantity, lot_size }
+    }
+
+    /// Check if this is a long position.
+    pub fn is_long(&self) -> bool {
+        self.quantity > 0
+    }
+
+    /// Check if this is a short position.
+    pub fn is_short(&self) -> bool {
+        self.quantity < 0
+    }
+}
+
+/// Configuration for spread backtest.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct SpreadConfig {
+    /// Base backtest configuration.
+    pub base: BacktestConfig,
+    /// Spread type.
+    pub spread_type: SpreadType,
+    /// Leg configurations.
+    pub leg_configs: Vec<LegConfig>,
+    /// Maximum loss threshold (optional, for early exit).
+    pub max_loss: Option<f64>,
+    /// Target profit threshold (optional, for early exit).
+    pub target_profit: Option<f64>,
+    /// Whether to close at end of day.
+    pub close_at_eod: bool,
+}
+
+impl Default for SpreadConfig {
+    fn default() -> Self {
+        Self {
+            base: BacktestConfig::default(),
+            spread_type: SpreadType::Custom,
+            leg_configs: Vec::new(),
+            max_loss: None,
+            target_profit: None,
+            close_at_eod: false,
+        }
+    }
+}
+
+/// State for a single leg position.
+#[derive(Debug, Clone)]
+struct LegPosition {
+    /// Entry premium price.
+    pub entry_premium: f64,
+    /// Entry index.
+    #[allow(dead_code)]
+    pub entry_idx: usize,
+    /// Current premium price.
+    pub current_premium: f64,
+    /// Leg configuration.
+    pub config: LegConfig,
+}
+
+impl LegPosition {
+    fn new(config: LegConfig, entry_premium: f64, entry_idx: usize) -> Self {
+        Self { entry_premium, entry_idx, current_premium: entry_premium, config }
+    }
+
+    /// Calculate unrealized P&L for this leg.
+    fn unrealized_pnl(&self) -> f64 {
+        // For short positions: profit when premium decreases
+        // For long positions: profit when premium increases
+        let premium_change = self.current_premium - self.entry_premium;
+        let quantity = self.config.quantity as f64;
+        let lot_size = self.config.lot_size as f64;
+        -quantity * premium_change * lot_size
+    }
+}
+
+/// Spread position state.
+#[derive(Debug, Clone)]
+struct SpreadPosition {
+    /// Individual leg positions.
+    pub legs: Vec<LegPosition>,
+    /// Entry bar index.
+    pub entry_idx: usize,
+    /// Entry net premium (positive = credit, negative = debit).
+    pub entry_net_premium: f64,
+    /// Entry timestamp.
+    pub entry_time: i64,
+    /// Whether position is open.
+    pub is_open: bool,
+}
+
+impl SpreadPosition {
+    fn new(legs: Vec<LegPosition>, entry_idx: usize, entry_time: i64) -> Self {
+        let entry_net_premium: f64 = legs
+            .iter()
+            .map(|leg| leg.entry_premium * leg.config.quantity as f64 * leg.config.lot_size as f64)
+            .sum();
+
+        Self { legs, entry_idx, entry_net_premium, entry_time, is_open: true }
+    }
+
+    /// Calculate total unrealized P&L across all legs.
+    fn total_unrealized_pnl(&self) -> f64 {
+        self.legs.iter().map(|leg| leg.unrealized_pnl()).sum()
+    }
+
+    /// Update leg premiums.
+    fn update_premiums(&mut self, leg_premiums: &[f64]) {
+        for (leg, &premium) in self.legs.iter_mut().zip(leg_premiums.iter()) {
+            leg.current_premium = premium;
+        }
+    }
+
+    /// Close the position and return P&L.
+    fn close(&mut self) -> f64 {
+        self.is_open = false;
+        self.total_unrealized_pnl()
+    }
+}
+
+/// Spread backtest runner.
+pub struct SpreadBacktest {
+    config: SpreadConfig,
+}
+
+impl SpreadBacktest {
+    /// Create a new spread backtest.
+    pub fn new(config: SpreadConfig) -> Self {
+        Self { config }
+    }
+
+    /// Run the spread backtest.
+    ///
+    /// # Arguments
+    /// * `timestamps` - Timestamp array
+    /// * `underlying_close` - Underlying close prices
+    /// * `legs_premiums` - Premium series for each leg (Vec of Vec)
+    /// * `entries` - Entry signals
+    /// * `exits` - Exit signals
+    ///
+    /// # Returns
+    /// Backtest result with metrics, trades, and equity curve
+    pub fn run(
+        &self,
+        timestamps: &[i64],
+        _underlying_close: &[f64],
+        legs_premiums: &[Vec<f64>],
+        entries: &[bool],
+        exits: &[bool],
+    ) -> BacktestResult {
+        let n = timestamps.len();
+
+        // Validate inputs
+        if legs_premiums.len() != self.config.leg_configs.len() {
+            return self.empty_result(n);
+        }
+
+        for premiums in legs_premiums {
+            if premiums.len() != n {
+                return self.empty_result(n);
+            }
+        }
+
+        let mut metrics = StreamingMetrics::with_initial_capital(self.config.base.initial_capital);
+        let mut equity_curve = Vec::with_capacity(n);
+        let mut drawdown_curve = Vec::with_capacity(n);
+        let mut returns = Vec::with_capacity(n);
+        let mut trades: Vec<Trade> = Vec::new();
+        let mut trade_id: u64 = 0;
+
+        let mut cash = self.config.base.initial_capital;
+        let mut position: Option<SpreadPosition> = None;
+        let mut prev_equity = cash;
+
+        // Single-pass O(n) algorithm
+        for i in 0..n {
+            // Get current leg premiums
+            let current_premiums: Vec<f64> = legs_premiums.iter().map(|p| p[i]).collect();
+
+            // Update position premiums if open
+            if let Some(ref mut pos) = position {
+                pos.update_premiums(&current_premiums);
+            }
+
+            // Calculate unrealized P&L for exit checks
+            let unrealized_pnl = position.as_ref().map(|p| p.total_unrealized_pnl()).unwrap_or(0.0);
+
+            // Check for exit signals or conditions
+            let should_exit = position.is_some()
+                && (exits[i]
+                    || self.check_max_loss(&position, unrealized_pnl)
+                    || self.check_target_profit(&position, unrealized_pnl));
+
+            if should_exit {
+                if let Some(mut pos) = position.take() {
+                    let pnl = pos.close();
+                    let fees = self.calculate_fees(&pos);
+                    let net_pnl = pnl - fees;
+
+                    cash += net_pnl;
+
+                    // Record trade
+                    trade_id += 1;
+                    let exit_reason = if exits[i] {
+                        ExitReason::Signal
+                    } else if self.check_max_loss(&Some(pos.clone()), pnl) {
+                        ExitReason::StopLoss
+                    } else {
+                        ExitReason::TakeProfit
+                    };
+
+                    let entry_premium = pos.entry_net_premium;
+                    let exit_premium: f64 = current_premiums
+                        .iter()
+                        .zip(self.config.leg_configs.iter())
+                        .map(|(&p, cfg)| p * cfg.quantity as f64 * cfg.lot_size as f64)
+                        .sum();
+
+                    trades.push(Trade {
+                        id: trade_id,
+                        symbol: "SPREAD".to_string(),
+                        entry_idx: pos.entry_idx,
+                        exit_idx: i,
+                        entry_price: entry_premium,
+                        exit_price: exit_premium,
+                        size: 1.0,
+                        direction: Direction::Long, // Spreads are treated as "long spread"
+                        pnl: net_pnl,
+                        return_pct: if entry_premium.abs() > 0.0 {
+                            net_pnl / entry_premium.abs() * 100.0
+                        } else {
+                            0.0
+                        },
+                        entry_time: pos.entry_time,
+                        exit_time: timestamps[i],
+                        fees,
+                        exit_reason,
+                    });
+
+                    metrics.record_trade(
+                        net_pnl,
+                        net_pnl / entry_premium.abs() * 100.0,
+                        i - pos.entry_idx,
+                    );
+                }
+            }
+
+            // Check for entry signals
+            if position.is_none() && entries[i] {
+                let legs: Vec<LegPosition> = self
+                    .config
+                    .leg_configs
+                    .iter()
+                    .zip(current_premiums.iter())
+                    .map(|(cfg, &premium)| LegPosition::new(cfg.clone(), premium, i))
+                    .collect();
+
+                let new_position = SpreadPosition::new(legs, i, timestamps[i]);
+
+                // Calculate entry fees
+                let entry_fees = self.calculate_entry_fees(&new_position);
+                cash -= entry_fees;
+
+                position = Some(new_position);
+            }
+
+            // Update equity tracking
+            let equity = cash + position.as_ref().map(|p| p.total_unrealized_pnl()).unwrap_or(0.0);
+            equity_curve.push(equity);
+
+            let daily_return =
+                if prev_equity > 0.0 { (equity - prev_equity) / prev_equity } else { 0.0 };
+            returns.push(daily_return);
+            prev_equity = equity;
+
+            // Update drawdown
+            metrics.update_equity(equity);
+            drawdown_curve.push(metrics.current_drawdown_pct());
+        }
+
+        // Close any remaining open position at end
+        if let Some(mut pos) = position.take() {
+            let pnl = pos.close();
+            let fees = self.calculate_fees(&pos);
+            cash += pnl - fees;
+        }
+
+        // Finalize metrics
+        let final_metrics = metrics.finalize(self.config.base.initial_capital, cash, &returns);
+
+        BacktestResult { metrics: final_metrics, equity_curve, drawdown_curve, trades, returns }
+    }
+
+    /// Check if max loss threshold is hit.
+    fn check_max_loss(&self, _position: &Option<SpreadPosition>, unrealized_pnl: f64) -> bool {
+        if let Some(max_loss) = self.config.max_loss {
+            if unrealized_pnl < -max_loss {
+                return true;
+            }
+        }
+        false
+    }
+
+    /// Check if target profit threshold is hit.
+    fn check_target_profit(&self, _position: &Option<SpreadPosition>, unrealized_pnl: f64) -> bool {
+        if let Some(target) = self.config.target_profit {
+            if unrealized_pnl > target {
+                return true;
+            }
+        }
+        false
+    }
+
+    /// Calculate entry fees for a position.
+    fn calculate_entry_fees(&self, position: &SpreadPosition) -> f64 {
+        let total_premium: f64 = position
+            .legs
+            .iter()
+            .map(|leg| leg.entry_premium.abs() * leg.config.lot_size as f64)
+            .sum();
+        total_premium * self.config.base.fees
+    }
+
+    /// Calculate exit fees for a position.
+    fn calculate_fees(&self, position: &SpreadPosition) -> f64 {
+        let total_premium: f64 = position
+            .legs
+            .iter()
+            .map(|leg| leg.current_premium.abs() * leg.config.lot_size as f64)
+            .sum();
+        total_premium * self.config.base.fees * 2.0 // Entry + Exit
+    }
+
+    /// Create an empty result (used for validation failures).
+    fn empty_result(&self, n: usize) -> BacktestResult {
+        BacktestResult {
+            metrics: BacktestMetrics::default(),
+            equity_curve: vec![self.config.base.initial_capital; n],
+            drawdown_curve: vec![0.0; n],
+            trades: Vec::new(),
+            returns: vec![0.0; n],
+        }
+    }
+}
+
+/// Convenience function to create a straddle spread config.
+pub fn create_straddle_config(
+    base: BacktestConfig,
+    strike: f64,
+    lot_size: usize,
+    short: bool,
+) -> SpreadConfig {
+    let quantity = if short { -1 } else { 1 };
+    SpreadConfig {
+        base,
+        spread_type: SpreadType::Straddle,
+        leg_configs: vec![
+            LegConfig::new(OptionType::Call, strike, quantity, lot_size),
+            LegConfig::new(OptionType::Put, strike, quantity, lot_size),
+        ],
+        ..Default::default()
+    }
+}
+
+/// Convenience function to create a strangle spread config.
+pub fn create_strangle_config(
+    base: BacktestConfig,
+    call_strike: f64,
+    put_strike: f64,
+    lot_size: usize,
+    short: bool,
+) -> SpreadConfig {
+    let quantity = if short { -1 } else { 1 };
+    SpreadConfig {
+        base,
+        spread_type: SpreadType::Strangle,
+        leg_configs: vec![
+            LegConfig::new(OptionType::Call, call_strike, quantity, lot_size),
+            LegConfig::new(OptionType::Put, put_strike, quantity, lot_size),
+        ],
+        ..Default::default()
+    }
+}
+
+/// Convenience function to create an iron condor spread config.
+pub fn create_iron_condor_config(
+    base: BacktestConfig,
+    short_put_strike: f64,
+    long_put_strike: f64,
+    short_call_strike: f64,
+    long_call_strike: f64,
+    lot_size: usize,
+) -> SpreadConfig {
+    SpreadConfig {
+        base,
+        spread_type: SpreadType::IronCondor,
+        leg_configs: vec![
+            LegConfig::new(OptionType::Put, short_put_strike, -1, lot_size),
+            LegConfig::new(OptionType::Put, long_put_strike, 1, lot_size),
+            LegConfig::new(OptionType::Call, short_call_strike, -1, lot_size),
+            LegConfig::new(OptionType::Call, long_call_strike, 1, lot_size),
+        ],
+        ..Default::default()
+    }
+}
+
+/// Convenience function to create a vertical spread config.
+pub fn create_vertical_spread_config(
+    base: BacktestConfig,
+    option_type: OptionType,
+    long_strike: f64,
+    short_strike: f64,
+    lot_size: usize,
+) -> SpreadConfig {
+    let spread_type = match option_type {
+        OptionType::Call => SpreadType::VerticalCall,
+        OptionType::Put => SpreadType::VerticalPut,
+    };
+
+    SpreadConfig {
+        base,
+        spread_type,
+        leg_configs: vec![
+            LegConfig::new(option_type, long_strike, 1, lot_size),
+            LegConfig::new(option_type, short_strike, -1, lot_size),
+        ],
+        ..Default::default()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::core::types::StopConfig;
+    use crate::core::types::TargetConfig;
+
+    fn sample_data() -> (Vec<i64>, Vec<f64>, Vec<Vec<f64>>, Vec<bool>, Vec<bool>) {
+        let n = 20;
+        let timestamps: Vec<i64> = (0..n as i64).collect();
+        let underlying: Vec<f64> = (100..120).map(|x| x as f64).collect();
+
+        // Call and Put premiums
+        let call_premiums: Vec<f64> = (0..n).map(|i| 5.0 + (i as f64 * 0.2)).collect();
+        let put_premiums: Vec<f64> = (0..n).map(|i| 5.0 - (i as f64 * 0.1)).collect();
+
+        let legs_premiums = vec![call_premiums, put_premiums];
+
+        let entries = vec![
+            false, true, false, false, false, false, false, false, false, false, false, false,
+            false, false, false, false, false, false, false, false,
+        ];
+        let exits = vec![
+            false, false, false, false, false, false, false, false, false, true, false, false,
+            false, false, false, false, false, false, false, false,
+        ];
+
+        (timestamps, underlying, legs_premiums, entries, exits)
+    }
+
+    #[test]
+    fn test_straddle_backtest() {
+        let base_config = BacktestConfig {
+            initial_capital: 100_000.0,
+            fees: 0.001,
+            slippage: 0.0,
+            stop: StopConfig::None,
+            target: TargetConfig::None,
+            upon_bar_close: true,
+        };
+
+        let config = create_straddle_config(base_config, 100.0, 50, true);
+        let backtest = SpreadBacktest::new(config);
+
+        let (timestamps, underlying, legs_premiums, entries, exits) = sample_data();
+
+        let result = backtest.run(&timestamps, &underlying, &legs_premiums, &entries, &exits);
+
+        assert_eq!(result.trades.len(), 1);
+        assert!(result.equity_curve.len() == timestamps.len());
+    }
+
+    #[test]
+    fn test_iron_condor_backtest() {
+        let base_config = BacktestConfig::default();
+
+        let config = create_iron_condor_config(
+            base_config,
+            95.0,  // short put
+            90.0,  // long put
+            105.0, // short call
+            110.0, // long call
+            50,
+        );
+
+        let backtest = SpreadBacktest::new(config);
+
+        let n = 20;
+        let timestamps: Vec<i64> = (0..n as i64).collect();
+        let underlying: Vec<f64> = vec![100.0; n];
+
+        // Four legs: short put, long put, short call, long call
+        let legs_premiums = vec![
+            vec![3.0; n], // short put
+            vec![1.5; n], // long put
+            vec![3.0; n], // short call
+            vec![1.5; n], // long call
+        ];
+
+        let mut entries = vec![false; n];
+        entries[1] = true;
+
+        let mut exits = vec![false; n];
+        exits[15] = true;
+
+        let result = backtest.run(&timestamps, &underlying, &legs_premiums, &entries, &exits);
+
+        assert_eq!(result.trades.len(), 1);
+    }
+}
@@ -4,5 +4,5 @@ requires-python = ">=3.10"

 [[package]]
 name = "raptorbt"
-version = "0.1.0"
+version = "0.2.0"
 source = { editable = "." }
Author	SHA1	Message	Date
vatsal	ab568cc9fb	Merge pull request #9 from alphabench/feat/porfolio-simulation feat: add Monte Carlo portfolio simulation and bump to 0.3.1	2026-02-17 00:36:45 +05:30
porcelaincode	4d4ea2e5e9	feat: add Monte Carlo portfolio simulation and bump to 0.3.1 - Add Monte Carlo forward simulation using Geometric Brownian Motion - Support correlated multi-asset simulation with Cholesky decomposition - Implement parallel execution via Rayon for performance - Expose simulate_portfolio_mc function in Python bindings - Update version from 0.3.0 to 0.3.1 across all project files	2026-02-17 00:35:20 +05:30
vatsal	a82ddc598a	Merge pull request #8 from alphabench/feat/instrument-level-config feat: add instrument level config and bump to 0.3.0	2026-02-10 05:05:38 +05:30
porcelaincode	bb6ce05c57	feat: add instrument level config and bump to 0.3.0	2026-02-10 05:03:39 +05:30
vatsal	aad09da117	Merge pull request #7 from alphabench/fix/spread-backtest feat: add new backtest functions	2026-02-08 06:06:30 +05:30
porcelaincode	c711e9ce8e	feat: add new backtest functions	2026-02-08 06:04:43 +05:30
vatsal	4d0d4cbfa3	feat: update version to 0.2.1 and add rolling min/max indicators (#6 ) * feat: add session tracking and multi-leg spread backtesting Add SessionTracker for trading session management: - Market hours detection (pre-open, trading, squareoff, post-close) - Session boundary tracking with configurable timezone - Squareoff time support for intraday strategies - Session high/low/open price tracking Add SpreadBacktest for multi-leg options strategies: - Support for straddles, strangles, vertical spreads, iron condors - Coordinated entry/exit across all legs - Net premium P&L calculation with max loss/target profit exits - Helper functions for common spread configurations Extend StreamingMetrics for backtest integration: - Add equity and drawdown tracking (update_equity, current_drawdown_pct) - Add trade recording (record_trade, record_fees) - Add finalize() method to produce BacktestMetrics - Add with_initial_capital() constructor Bump version to 0.2.0. * chore: bump up version to 0.2.0 * feat: update version to 0.2.1 and add rolling min/max indicators * fix: formatting	2026-02-02 04:24:45 +05:30
vatsal	03ac0192b7	Merge pull request #5 from alphabench/chore/fix-readme chore: fix README for relevance	2026-01-30 03:54:47 +05:30
porcelaincode	baa87b476b	chore: fix README for relevance	2026-01-30 03:54:14 +05:30
vatsal	f4a40617c0	Merge pull request #4 from alphabench/chore/project-metadata update project metadata	2026-01-29 23:12:29 +05:30
porcelaincode	196f63f5c3	update project metadata and documentation for clarity and branding	2026-01-29 23:11:15 +05:30
vatsal	5ca413ebbf	Fix/release workflow python (#3 ) * Fix release workflow: Python compatibility issues - Linux: Add --find-interpreter for cross-compilation - macOS/Windows: Pin Python to 3.12 (PyO3 0.20.3 max supported) * Fix Linux release: limit Python versions to 3.10-3.12 PyO3 0.20.3 only supports up to Python 3.12. Using --find-interpreter detected Python 3.13/3.14 in the manylinux container which caused build failures.	2026-01-28 16:05:18 +05:30
vatsal	ca2965aade	Fix release workflow: Python compatibility issues (#2 ) - Linux: Add --find-interpreter for cross-compilation - macOS/Windows: Pin Python to 3.12 (PyO3 0.20.3 max supported)	2026-01-28 15:54:37 +05:30