deveshc23
feat: Add Free Gradio Space support, Git LFS tracking for data artifacts, and Quant Allocator
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"""Event-driven long-only portfolio simulation with next-bar-open execution."""
from __future__ import annotations
import math
from collections.abc import Callable
from dataclasses import asdict, dataclass
from datetime import datetime
from statistics import fmean
from typing import Any
from uuid import uuid4
from drift_quant.backtesting.strategies import Strategy
from drift_quant.nse_data.loader import LoadedNseDataset
@dataclass(frozen=True, slots=True)
class BacktestConfig:
"""Visible simulation assumptions; costs are configurable research assumptions."""
initial_capital: float = 1_000_000.0
max_gross_exposure: float = 0.95
transaction_cost_bps: float = 10.0
slippage_bps: float = 5.0
allow_overnight: bool = True
force_close_at_end: bool = True
def __post_init__(self) -> None:
if self.initial_capital <= 0:
raise ValueError("Initial capital must be positive.")
if not 0 < self.max_gross_exposure <= 1:
raise ValueError("Maximum gross exposure must be in (0, 1].")
if self.transaction_cost_bps < 0 or self.slippage_bps < 0:
raise ValueError("Cost assumptions must not be negative.")
@dataclass(frozen=True, slots=True)
class Trade:
symbol: str
entry_time: datetime
exit_time: datetime
quantity: int
entry_price: float
exit_price: float
gross_pnl: float
costs: float
net_pnl: float
exit_reason: str
@dataclass(frozen=True, slots=True)
class EquityPoint:
timestamp: datetime
equity: float
gross_exposure: float
@dataclass(frozen=True, slots=True)
class BacktestResult:
experiment_id: str
strategy_name: str
strategy_version: str
dataset_id: str
config: BacktestConfig
trades: tuple[Trade, ...]
equity_curve: tuple[EquityPoint, ...]
metrics: dict[str, float | int | None]
def to_dict(self, max_equity_points: int | None = 2500) -> dict[str, Any]:
points = list(self.equity_curve)
if max_equity_points is not None and len(points) > max_equity_points:
step = (len(points) - 1) / (max_equity_points - 1)
indices = {round(i * step) for i in range(max_equity_points)}
points = [p for i, p in enumerate(points) if i in indices]
return {
"experiment_id": self.experiment_id,
"strategy_name": self.strategy_name,
"strategy_version": self.strategy_version,
"dataset_id": self.dataset_id,
"config": asdict(self.config),
"trades": [
{
**asdict(trade),
"entry_time": trade.entry_time.isoformat(sep=" "),
"exit_time": trade.exit_time.isoformat(sep=" "),
}
for trade in self.trades
],
"equity_curve": [
{
**asdict(point),
"timestamp": point.timestamp.isoformat(sep=" "),
}
for point in points
],
"metrics": self.metrics,
}
@dataclass(slots=True)
class _Position:
quantity: int
entry_time: datetime
entry_price: float
entry_cost: float
@dataclass(frozen=True, slots=True)
class _PendingOrder:
symbol: str
target_long: bool
decision_time: datetime
def _side_adjusted_price(open_price: float, is_buy: bool, slippage_bps: float) -> float:
adjustment = slippage_bps / 10_000
return open_price * (1 + adjustment if is_buy else 1 - adjustment)
def _commission(notional: float, cost_bps: float) -> float:
return notional * cost_bps / 10_000
def _mark_equity(
cash: float, positions: dict[str, _Position], latest_prices: dict[str, float]
) -> tuple[float, float]:
gross_exposure = sum(
position.quantity * latest_prices[symbol]
for symbol, position in positions.items()
if symbol in latest_prices
)
return cash + gross_exposure, gross_exposure
def _daily_equity(points: tuple[EquityPoint, ...]) -> list[float]:
last_by_date: dict[object, float] = {}
for point in points:
last_by_date[point.timestamp.date()] = point.equity
return [last_by_date[key] for key in sorted(last_by_date)]
def _metrics(
initial_capital: float, points: tuple[EquityPoint, ...], trades: tuple[Trade, ...], costs: float
) -> dict[str, float | int | None]:
if not points:
return {
"cumulative_return": 0.0,
"annualized_return": None,
"annualized_volatility": None,
"sharpe_ratio": None,
"sortino_ratio": None,
"maximum_drawdown": 0.0,
"trade_count": 0,
"transaction_costs": costs,
}
final_equity = points[-1].equity
cumulative_return = final_equity / initial_capital - 1
daily_equity = _daily_equity(points)
daily_returns = [
daily_equity[index] / daily_equity[index - 1] - 1
for index in range(1, len(daily_equity))
if daily_equity[index - 1] > 0
]
annualized_return: float | None = None
annualized_volatility: float | None = None
sharpe: float | None = None
sortino: float | None = None
if len(daily_equity) >= 2 and daily_equity[0] > 0:
years = max((points[-1].timestamp - points[0].timestamp).days / 365.25, 1 / 365.25)
annualized_return = (final_equity / initial_capital) ** (1 / years) - 1
if len(daily_returns) >= 2:
mean_return = fmean(daily_returns)
variance = fmean([(value - mean_return) ** 2 for value in daily_returns])
annualized_volatility = math.sqrt(variance) * math.sqrt(252)
if annualized_volatility > 0:
sharpe = mean_return / math.sqrt(variance) * math.sqrt(252)
downside = [min(value, 0.0) for value in daily_returns]
downside_deviation = math.sqrt(fmean([value**2 for value in downside]))
if downside_deviation > 0:
sortino = mean_return / downside_deviation * math.sqrt(252)
peak = initial_capital
maximum_drawdown = 0.0
for point in points:
peak = max(peak, point.equity)
maximum_drawdown = min(maximum_drawdown, point.equity / peak - 1)
wins = [trade.net_pnl for trade in trades if trade.net_pnl > 0]
losses = [trade.net_pnl for trade in trades if trade.net_pnl < 0]
gross_profit = sum(wins)
gross_loss = abs(sum(losses))
holding_minutes = [
(trade.exit_time - trade.entry_time).total_seconds() / 60 for trade in trades
]
return {
"cumulative_return": cumulative_return,
"annualized_return": annualized_return,
"annualized_volatility": annualized_volatility,
"sharpe_ratio": sharpe,
"sortino_ratio": sortino,
"maximum_drawdown": maximum_drawdown,
"trade_count": len(trades),
"win_rate": len(wins) / len(trades) if trades else None,
"average_win": fmean(wins) if wins else None,
"average_loss": fmean(losses) if losses else None,
"profit_factor": gross_profit / gross_loss if gross_loss else None,
"average_holding_minutes": fmean(holding_minutes) if holding_minutes else None,
"transaction_costs": costs,
"final_equity": final_equity,
}
def run_backtest(
dataset: LoadedNseDataset,
strategy: Strategy,
config: BacktestConfig,
progress_callback: Callable[[float, datetime, float, int, Trade | None], None] | None = None,
) -> BacktestResult:
"""Run completed-bar decisions with fills only at the next available bar open.
The engine allocates the allowed gross exposure equally across the configured
symbols. It does not use current-bar close to fill an order.
"""
all_events = sorted(
(bar for bars in dataset.bars_by_symbol.values() for bar in bars),
key=lambda bar: (bar.timestamp, bar.symbol),
)
if not all_events:
raise ValueError("Dataset has no valid bars for the selected universe.")
allocation_per_symbol = (
config.initial_capital * config.max_gross_exposure / len(dataset.symbols)
)
cash = config.initial_capital
positions: dict[str, _Position] = {}
pending: dict[str, _PendingOrder] = {}
latest_prices: dict[str, float] = {}
trades: list[Trade] = []
equity_curve: list[EquityPoint] = []
total_costs = 0.0
total_events = len(all_events)
report_interval = max(200, total_events // 60)
current_ts: datetime | None = None
last_trade: Trade | None = None
for idx, bar in enumerate(all_events):
latest_prices[bar.symbol] = bar.close
order = pending.pop(bar.symbol, None)
if order is not None:
if order.target_long and bar.symbol not in positions:
fill_price = _side_adjusted_price(bar.open, True, config.slippage_bps)
quantity = int(allocation_per_symbol // fill_price)
notional = quantity * fill_price
cost = _commission(notional, config.transaction_cost_bps)
if quantity > 0 and cash >= notional + cost:
cash -= notional + cost
total_costs += cost
positions[bar.symbol] = _Position(
quantity=quantity,
entry_time=bar.timestamp,
entry_price=fill_price,
entry_cost=cost,
)
elif not order.target_long and bar.symbol in positions:
position = positions.pop(bar.symbol)
fill_price = _side_adjusted_price(bar.open, False, config.slippage_bps)
notional = position.quantity * fill_price
exit_cost = _commission(notional, config.transaction_cost_bps)
cash += notional - exit_cost
total_costs += exit_cost
gross_pnl = position.quantity * (fill_price - position.entry_price)
costs = position.entry_cost + exit_cost
new_trade = Trade(
symbol=bar.symbol,
entry_time=position.entry_time,
exit_time=bar.timestamp,
quantity=position.quantity,
entry_price=position.entry_price,
exit_price=fill_price,
gross_pnl=gross_pnl,
costs=costs,
net_pnl=gross_pnl - costs,
exit_reason="strategy_signal",
)
trades.append(new_trade)
last_trade = new_trade
desired = strategy.target(bar.symbol, bar)
if desired is not None:
is_long = bar.symbol in positions
existing_pending = pending.get(bar.symbol)
if desired != is_long and (
existing_pending is None or existing_pending.target_long != desired
):
pending[bar.symbol] = _PendingOrder(
symbol=bar.symbol, target_long=desired, decision_time=bar.timestamp
)
if current_ts is None or bar.timestamp != current_ts:
equity, exposure = _mark_equity(cash, positions, latest_prices)
equity_curve.append(
EquityPoint(timestamp=bar.timestamp, equity=equity, gross_exposure=exposure)
)
current_ts = bar.timestamp
if progress_callback is not None and (idx % report_interval == 0):
pct = round((idx + 1) / total_events * 100, 1)
progress_callback(pct, bar.timestamp, equity, len(trades), last_trade)
if config.force_close_at_end:
for symbol, position in list(positions.items()):
bar = dataset.bars_by_symbol[symbol][-1]
# Explicit end-of-data liquidation assumption; it is never treated as a next-bar fill.
fill_price = _side_adjusted_price(bar.close, False, config.slippage_bps)
notional = position.quantity * fill_price
exit_cost = _commission(notional, config.transaction_cost_bps)
cash += notional - exit_cost
total_costs += exit_cost
gross_pnl = position.quantity * (fill_price - position.entry_price)
costs = position.entry_cost + exit_cost
new_trade = Trade(
symbol=symbol,
entry_time=position.entry_time,
exit_time=bar.timestamp,
quantity=position.quantity,
entry_price=position.entry_price,
exit_price=fill_price,
gross_pnl=gross_pnl,
costs=costs,
net_pnl=gross_pnl - costs,
exit_reason="end_of_data_close_assumption",
)
trades.append(new_trade)
last_trade = new_trade
del positions[symbol]
final_time = max(bar.timestamp for bar in all_events)
equity_curve.append(EquityPoint(timestamp=final_time, equity=cash, gross_exposure=0.0))
if progress_callback is not None:
final_eq = equity_curve[-1].equity if equity_curve else cash
progress_callback(100.0, all_events[-1].timestamp, final_eq, len(trades), last_trade)
immutable_points = tuple(equity_curve)
immutable_trades = tuple(trades)
return BacktestResult(
experiment_id=str(uuid4()),
strategy_name=strategy.name,
strategy_version=strategy.version,
dataset_id=dataset.dataset_id,
config=config,
trades=immutable_trades,
equity_curve=immutable_points,
metrics=_metrics(config.initial_capital, immutable_points, immutable_trades, total_costs),
)