🧿 Backtest Kit

A TypeScript framework for backtesting and live trading strategies on multi-asset, crypto, forex or DEX (peer-to-peer marketplace), spot, futures with crash-safe persistence, signal validation, and AI optimization.

Build reliable trading systems: backtest on historical data, deploy live bots with recovery, and optimize strategies using LLMs like Ollama.

📚 API Reference | 🌟 Quick Start | 📰 Article

🚀 Quick Start

🎯 The Fastest Way: Sidekick CLI

Create a production-ready trading bot in seconds:

# Create project with npx (recommended)
npx -y @backtest-kit/sidekick my-trading-bot
cd my-trading-bot
npm start

📦 Manual Installation

Want to see the code? 👉 Demo app 👈

npm install backtest-kit ccxt ollama uuid

✨ Why Choose Backtest Kit?

• 🚀 Production-Ready: Seamless switch between backtest/live modes; identical code across environments.
• 💾 Crash-Safe: Atomic persistence recovers states after crashes, preventing duplicates or losses.
• ✅ Validation: Checks signals for TP/SL logic, risk/reward ratios, and portfolio limits.
• 🔄 Efficient Execution: Streaming architecture for large datasets; VWAP pricing for realism.
• 🤖 AI Integration: LLM-powered strategy generation (Optimizer) with multi-timeframe analysis.
• 📊 Reports & Metrics: Auto Markdown reports with PNL, Sharpe Ratio, win rate, and more.
• 🛡️ Risk Management: Custom rules for position limits, time windows, and multi-strategy coordination.
• 🔌 Pluggable: Custom data sources (CCXT), persistence (file/Redis), and sizing calculators.
• 🗃️ Transactional Live Orders: Broker adapter intercepts every trade mutation before internal state changes — exchange rejection rolls back the operation atomically.
• 🧪 Tested: 350+ unit/integration tests for validation, recovery, and events.
• 🔓 Self hosted: Zero dependency on third-party node_modules or platforms; run entirely in your own environment.

📋 Supported Order Types

With the calculation of PnL

• Market/Limit entries
• TP/SL/OCO exits
• Grid with auto-cancel on unmet conditions
• Partial profit/loss levels
• Trailing stop-loss
• Breakeven protection
• Stop limit entries (before OCO)
• Dollar cost averaging

📚 Code Samples

⚙️ Basic Configuration

import { setLogger, setConfig } from 'backtest-kit';

// Enable logging
setLogger({
  log: console.log,
  debug: console.debug,
  info: console.info,
  warn: console.warn,
});

// Global config (optional)
setConfig({
  CC_PERCENT_SLIPPAGE: 0.1,  // % slippage
  CC_PERCENT_FEE: 0.1,       // % fee
  CC_SCHEDULE_AWAIT_MINUTES: 120,  // Pending signal timeout
});

🔧 Register Components

import ccxt from 'ccxt';
import { addExchangeSchema, addStrategySchema, addFrameSchema, addRiskSchema } from 'backtest-kit';

// Exchange (data source)
addExchangeSchema({
  exchangeName: 'binance',
  getCandles: async (symbol, interval, since, limit) => {
    const exchange = new ccxt.binance();
    const ohlcv = await exchange.fetchOHLCV(symbol, interval, since.getTime(), limit);
    return ohlcv.map(([timestamp, open, high, low, close, volume]) => ({ timestamp, open, high, low, close, volume }));
  },
  formatPrice: (symbol, price) => price.toFixed(2),
  formatQuantity: (symbol, quantity) => quantity.toFixed(8),
});

// Risk profile
addRiskSchema({
  riskName: 'demo',
  validations: [
    // TP at least 1%
    ({ pendingSignal, currentPrice }) => {
      const { priceOpen = currentPrice, priceTakeProfit, position } = pendingSignal;
      const tpDistance = position === 'long' ? ((priceTakeProfit - priceOpen) / priceOpen) * 100 : ((priceOpen - priceTakeProfit) / priceOpen) * 100;
      if (tpDistance < 1) throw new Error(`TP too close: ${tpDistance.toFixed(2)}%`);
    },
    // R/R at least 2:1
    ({ pendingSignal, currentPrice }) => {
      const { priceOpen = currentPrice, priceTakeProfit, priceStopLoss, position } = pendingSignal;
      const reward = position === 'long' ? priceTakeProfit - priceOpen : priceOpen - priceTakeProfit;
      const risk = position === 'long' ? priceOpen - priceStopLoss : priceStopLoss - priceOpen;
      if (reward / risk < 2) throw new Error('Poor R/R ratio');
    },
  ],
});

// Time frame
addFrameSchema({
  frameName: '1d-test',
  interval: '1m',
  startDate: new Date('2025-12-01'),
  endDate: new Date('2025-12-02'),
});

💡 Example Strategy (with LLM)

import { v4 as uuid } from 'uuid';
import { addStrategySchema, dumpSignalData, getCandles } from 'backtest-kit';
import { json } from './utils/json.mjs';  // LLM wrapper
import { getMessages } from './utils/messages.mjs';  // Market data prep

addStrategySchema({
  strategyName: 'llm-strategy',
  interval: '5m',
  riskName: 'demo',
  getSignal: async (symbol) => {

    const candles1h = await getCandles(symbol, "1h", 24);
    const candles15m = await getCandles(symbol, "15m", 48);
    const candles5m = await getCandles(symbol, "5m", 60);
    const candles1m = await getCandles(symbol, "1m", 60);

    const messages = await getMessages(symbol, {
      candles1h,
      candles15m,
      candles5m,
      candles1m,
    });  // Calculate indicators / Fetch news

    const resultId = uuid();
    const signal = await json(messages);  // LLM generates signal
    await dumpSignalData(resultId, messages, signal);  // Log

    return { ...signal, id: resultId };
  },
});

🧪 Run Backtest

import { Backtest, listenSignalBacktest, listenDoneBacktest } from 'backtest-kit';

Backtest.background('BTCUSDT', {
  strategyName: 'llm-strategy',
  exchangeName: 'binance',
  frameName: '1d-test',
});

listenSignalBacktest((event) => console.log(event));
listenDoneBacktest(async (event) => {
  await Backtest.dump(event.symbol, event.strategyName);  // Generate report
});

📈 Run Live Trading

import { Live, listenSignalLive } from 'backtest-kit';

Live.background('BTCUSDT', {
  strategyName: 'llm-strategy',
  exchangeName: 'binance',  // Use API keys in .env
});

listenSignalLive((event) => console.log(event));

📡 Monitoring & Events

• Use listenRisk, listenError, listenPartialProfit/Loss for alerts.
• Dump reports: Backtest.dump(), Live.dump().

🌐 Global Configuration

Customize via setConfig():

• CC_SCHEDULE_AWAIT_MINUTES: Pending timeout (default: 120).
• CC_AVG_PRICE_CANDLES_COUNT: VWAP candles (default: 5).

💻 Developer Note

Backtest Kit is not a data-processing library - it is a time execution engine. Think of the engine as an async stream of time, where your strategy is evaluated step by step.

🔍 How PNL Works

These three functions work together to dynamically manage the position. To reduce position linearity, by default, each DCA entry is formatted as a fixed unit of $100. This can be changed. No mathematical knowledge is required.

Public API:

• commitAverageBuy — adds a new DCA entry. For LONG, only accepted when current price is below a new low. Silently rejected otherwise. This prevents averaging up. Can be overridden using setConfig
• commitPartialProfit — closes X% of the position at a profit. Locks in gains while keeping exposure.
• commitPartialLoss — closes X% of the position at a loss. Cuts exposure before the stop-loss is hit.

Scenario: LONG entry @ 1000, 4 DCA attempts (1 rejected), 3 partials, closed at TP. totalInvested = $400 (4 × $100, rejected attempt not counted).

Entries

  entry#1 @ 1000  → 0.10000 coins
    commitPartialProfit(30%) @ 1150          ← cnt=1
  entry#2 @ 950   → 0.10526 coins
  entry#3 @ 880   → 0.11364 coins
    commitPartialLoss(20%)   @ 860           ← cnt=3
  entry#4 @ 920   → 0.10870 coins
    commitPartialProfit(40%) @ 1050          ← cnt=4
  entry#5 @ 980   ✗ REJECTED (980 > ep3≈929.92)
  totalInvested = $400

Partial#1 — commitPartialProfit @ 1150, 30%, cnt=1

  effectivePrice = hm(1000) = 1000
  costBasis = $100
  partialDollarValue = 30% × 100 = $30  → weight = 30/400 = 0.075
  pnl = (1150−1000)/1000 × 100 = +15.00%
  costBasis → $70
  coins sold: 0.03000 × 1150 = $34.50
  remaining:  0.07000

DCA after Partial#1

  entry#2 @ 950  (950 < ep1=1000 ✓ accepted)
  entry#3 @ 880  (880 < ep1=1000 ✓ accepted)
  coins: 0.07000 + 0.10526 + 0.11364 = 0.28890

Partial#2 — commitPartialLoss @ 860, 20%, cnt=3

  costBasis = 70 + 100 + 100 = $270
  ep2 = 270 / 0.28890 ≈ 934.58
  partialDollarValue = 20% × 270 = $54  → weight = 54/400 = 0.135
  pnl = (860−934.58)/934.58 × 100 ≈ −7.98%
  costBasis → $216
  coins sold: 0.05778 × 860 = $49.69
  remaining:  0.23112

DCA after Partial#2

  entry#4 @ 920  (920 < ep2=934.58 ✓ accepted)
  coins: 0.23112 + 0.10870 = 0.33982

Partial#3 — commitPartialProfit @ 1050, 40%, cnt=4

  costBasis = 216 + 100 = $316
  ep3 = 316 / 0.33982 ≈ 929.92
  partialDollarValue = 40% × 316 = $126.4  → weight = 126.4/400 = 0.316
  pnl = (1050−929.92)/929.92 × 100 ≈ +12.91%
  costBasis → $189.6
  coins sold: 0.13593 × 1050 = $142.72
  remaining:  0.20389

DCA after Partial#3 — rejected

  entry#5 @ 980  (980 > ep3≈929.92 ✗ REJECTED)

Close at TP @ 1200

  ep_final = ep3 ≈ 929.92  (no new entries)
  coins: 0.20389

  remainingDollarValue = 400 − 30 − 54 − 126.4 = $189.6
  weight = 189.6/400 = 0.474
  pnl = (1200−929.92)/929.92 × 100 ≈ +29.04%
  coins sold: 0.20389 × 1200 = $244.67

Result (toProfitLossDto)

  0.075 × (+15.00) = +1.125
  0.135 × (−7.98)  = −1.077
  0.316 × (+12.91) = +4.080
  0.474 × (+29.04) = +13.765
  ─────────────────────────────
                  ≈ +17.89%

  Cross-check (coins):
  34.50 + 49.69 + 142.72 + 244.67 = $471.58
  (471.58 − 400) / 400 × 100      = +17.90%  ✓

priceOpen is the harmonic mean of all accepted DCA entries. After each partial close (commitPartialProfit or commitPartialLoss), the remaining cost basis is carried forward into the harmonic mean calculation for subsequent entries — so priceOpen shifts after every partial, which in turn changes whether the next commitAverageBuy call will be accepted.

🔍 How Broker Transactional Integrity Works

Broker.useBrokerAdapter connects a live exchange (ccxt, Binance, etc.) to the framework with transaction safety. Every commit method fires before the internal position state mutates. If the exchange rejects the order, the fill times out, or the network fails, the adapter throws, the mutation is skipped, and backtest-kit retries automatically on the next tick.

Spot

import ccxt from "ccxt";
import { singleshot, sleep } from "functools-kit";
import {
  Broker,
  IBroker,
  BrokerSignalOpenPayload,
  BrokerSignalClosePayload,
  BrokerPartialProfitPayload,
  BrokerPartialLossPayload,
  BrokerTrailingStopPayload,
  BrokerTrailingTakePayload,
  BrokerBreakevenPayload,
  BrokerAverageBuyPayload,
} from "backtest-kit";

const FILL_POLL_INTERVAL_MS = 10_000;
const FILL_POLL_ATTEMPTS = 10;

/**
 * Sleep between cancelOrder and fetchBalance to allow Binance to settle the
 * cancellation — reads immediately after cancel may return stale data.
 */
const CANCEL_SETTLE_MS = 2_000;

/**
 * Slippage buffer for stop_loss_limit on Spot — limit price is set slightly
 * below stopPrice so the order fills even on a gap down instead of hanging.
 */
const STOP_LIMIT_SLIPPAGE = 0.995;

const getSpotExchange = singleshot(async () => {
  const exchange = new ccxt.binance({
    apiKey: process.env.BINANCE_API_KEY,
    secret: process.env.BINANCE_API_SECRET,
    options: {
      defaultType: "spot",
      adjustForTimeDifference: true,
      recvWindow: 60000,
    },
    enableRateLimit: true,
  });
  await exchange.loadMarkets();
  return exchange;
});

/**
 * Resolve base currency from market metadata — safe for all quote currencies (USDT, USDC, FDUSD, etc.)
 */
function getBase(exchange: ccxt.binance, symbol: string): string {
  return exchange.markets[symbol].base;
}

/**
 * Truncate qty to exchange precision, always rounding down.
 * Prevents over-selling due to floating point drift from fetchBalance.
 */
function truncateQty(exchange: ccxt.binance, symbol: string, qty: number): number {
  return parseFloat(exchange.amountToPrecision(symbol, qty, exchange.TRUNCATE));
}

/**
 * Fetch current free balance for base currency of symbol.
 */
async function fetchFreeQty(exchange: ccxt.binance, symbol: string): Promise<number> {
  const balance = await exchange.fetchBalance();
  const base    = getBase(exchange, symbol);
  return parseFloat(String(balance?.free?.[base] ?? 0));
}

/**
 * Cancel all orders in parallel — allSettled so a single failure (already filled,
 * network blip) does not leave remaining orders uncancelled.
 */
async function cancelAllOrders(exchange: ccxt.binance, orders: ccxt.Order[], symbol: string): Promise<void> {
  await Promise.allSettled(orders.map((o) => exchange.cancelOrder(o.id, symbol)));
}

/**
 * Place a stop_loss_limit sell order with a slippage buffer on the limit price.
 * stop_loss_limit requires both stopPrice (trigger) and price (limit fill).
 * Setting them equal risks non-fill on gap down — limit is offset by STOP_LIMIT_SLIPPAGE.
 */
async function createStopLossOrder(
  exchange: ccxt.binance,
  symbol: string,
  qty: number,
  stopPrice: number
): Promise<void> {
  const limitPrice = parseFloat(exchange.priceToPrecision(symbol, stopPrice * STOP_LIMIT_SLIPPAGE));
  await exchange.createOrder(symbol, "stop_loss_limit", "sell", qty, limitPrice, { stopPrice });
}

/**
 * Place a limit order and poll until filled (status === "closed").
 * On timeout: cancel the order, settle, check partial fill and sell it via market,
 * restore SL/TP on remaining position so it is never left unprotected, then throw.
 */
async function createLimitOrderAndWait(
  exchange: ccxt.binance,
  symbol: string,
  side: "buy" | "sell",
  qty: number,
  price: number,
  restore?: { tpPrice: number; slPrice: number }
): Promise<void> {
  const order = await exchange.createOrder(symbol, "limit", side, qty, price);

  for (let i = 0; i < FILL_POLL_ATTEMPTS; i++) {
    await sleep(FILL_POLL_INTERVAL_MS);
    const status = await exchange.fetchOrder(order.id, symbol);
    if (status.status === "closed") {
      return;
    }
  }

  await exchange.cancelOrder(order.id, symbol);

  // Wait for Binance to settle the cancellation before reading filled qty
  await sleep(CANCEL_SETTLE_MS);

  const final     = await exchange.fetchOrder(order.id, symbol);
  const filledQty = final.filled ?? 0;

  if (filledQty > 0) {
    // Sell partial fill via market to restore clean exchange state before backtest-kit retries
    const rollbackSide = side === "buy" ? "sell" : "buy";
    await exchange.createOrder(symbol, "market", rollbackSide, filledQty);
  }

  // Restore SL/TP on remaining position so it is not left unprotected during retry
  if (restore) {
    const remainingQty = truncateQty(exchange, symbol, await fetchFreeQty(exchange, symbol));
    if (remainingQty > 0) {
      await exchange.createOrder(symbol, "limit", "sell", remainingQty, restore.tpPrice);
      await createStopLossOrder(exchange, symbol, remainingQty, restore.slPrice);
    }
  }

  throw new Error(`Limit order ${order.id} [${side} ${qty} ${symbol} @ ${price}] not filled in time — partial fill rolled back, backtest-kit will retry`);
}

Broker.useBrokerAdapter(
  class implements IBroker {

    async waitForInit(): Promise<void> {
      await getSpotExchange();
    }

    async onSignalOpenCommit(payload: BrokerSignalOpenPayload): Promise<void> {
      const { symbol, cost, priceOpen, priceTakeProfit, priceStopLoss, position } = payload;

      // Spot does not support short selling — reject immediately so backtest-kit skips the mutation
      if (position === "short") {
        throw new Error(`SpotBrokerAdapter: short position is not supported on spot (symbol=${symbol})`);
      }

      const exchange = await getSpotExchange();

      const qty = truncateQty(exchange, symbol, cost / priceOpen);

      // Guard: truncation may produce 0 if cost/price is below lot size
      if (qty <= 0) {
        throw new Error(`Computed qty is zero for ${symbol} — cost=${cost}, price=${priceOpen}`);
      }

      const openPrice = parseFloat(exchange.priceToPrecision(symbol, priceOpen));
      const tpPrice   = parseFloat(exchange.priceToPrecision(symbol, priceTakeProfit));
      const slPrice   = parseFloat(exchange.priceToPrecision(symbol, priceStopLoss));

      // Entry: no restore needed — position does not exist yet if entry times out
      await createLimitOrderAndWait(exchange, symbol, "buy", qty, openPrice);

      // Post-fill: if TP/SL placement fails, position is open and unprotected — close via market
      try {
        await exchange.createOrder(symbol, "limit", "sell", qty, tpPrice);
        await createStopLossOrder(exchange, symbol, qty, slPrice);
      } catch (err) {
        await exchange.createOrder(symbol, "market", "sell", qty);
        throw err;
      }
    }

    async onSignalCloseCommit(payload: BrokerSignalClosePayload): Promise<void> {
      const { symbol, currentPrice, priceTakeProfit, priceStopLoss } = payload;
      const exchange = await getSpotExchange();

      const openOrders = await exchange.fetchOpenOrders(symbol);
      await cancelAllOrders(exchange, openOrders, symbol);
      await sleep(CANCEL_SETTLE_MS);

      const qty = truncateQty(exchange, symbol, await fetchFreeQty(exchange, symbol));

      // Position already closed by SL/TP on exchange — nothing to do, commit succeeds
      if (qty === 0) {
        return;
      }

      const closePrice = parseFloat(exchange.priceToPrecision(symbol, currentPrice));
      const tpPrice    = parseFloat(exchange.priceToPrecision(symbol, priceTakeProfit));
      const slPrice    = parseFloat(exchange.priceToPrecision(symbol, priceStopLoss));

      // Restore SL/TP if close times out so position is not left unprotected during retry
      await createLimitOrderAndWait(exchange, symbol, "sell", qty, closePrice, { tpPrice, slPrice });
    }

    async onPartialProfitCommit(payload: BrokerPartialProfitPayload): Promise<void> {
      const { symbol, percentToClose, currentPrice, priceTakeProfit, priceStopLoss } = payload;
      const exchange = await getSpotExchange();

      const openOrders = await exchange.fetchOpenOrders(symbol);
      await cancelAllOrders(exchange, openOrders, symbol);
      await sleep(CANCEL_SETTLE_MS);

      const totalQty = await fetchFreeQty(exchange, symbol);

      // Position may have already been closed by SL/TP on exchange — skip gracefully
      if (totalQty === 0) {
        throw new Error(`PartialProfit skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const qty          = truncateQty(exchange, symbol, totalQty * (percentToClose / 100));
      const remainingQty = truncateQty(exchange, symbol, totalQty - qty);
      const closePrice   = parseFloat(exchange.priceToPrecision(symbol, currentPrice));
      const tpPrice      = parseFloat(exchange.priceToPrecision(symbol, priceTakeProfit));
      const slPrice      = parseFloat(exchange.priceToPrecision(symbol, priceStopLoss));

      // Restore SL/TP on remaining qty if partial close times out so position is not left unprotected
      await createLimitOrderAndWait(exchange, symbol, "sell", qty, closePrice, { tpPrice, slPrice });

      // Restore SL/TP on remaining qty after successful partial close
      if (remainingQty > 0) {
        try {
          await exchange.createOrder(symbol, "limit", "sell", remainingQty, tpPrice);
          await createStopLossOrder(exchange, symbol, remainingQty, slPrice);
        } catch (err) {
          // Remaining position is unprotected — close via market
          await exchange.createOrder(symbol, "market", "sell", remainingQty);
          throw err;
        }
      }
    }

    async onPartialLossCommit(payload: BrokerPartialLossPayload): Promise<void> {
      const { symbol, percentToClose, currentPrice, priceTakeProfit, priceStopLoss } = payload;
      const exchange = await getSpotExchange();

      const openOrders = await exchange.fetchOpenOrders(symbol);
      await cancelAllOrders(exchange, openOrders, symbol);
      await sleep(CANCEL_SETTLE_MS);

      const totalQty = await fetchFreeQty(exchange, symbol);

      // Position may have already been closed by SL/TP on exchange — skip gracefully
      if (totalQty === 0) {
        throw new Error(`PartialLoss skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const qty          = truncateQty(exchange, symbol, totalQty * (percentToClose / 100));
      const remainingQty = truncateQty(exchange, symbol, totalQty - qty);
      const closePrice   = parseFloat(exchange.priceToPrecision(symbol, currentPrice));
      const tpPrice      = parseFloat(exchange.priceToPrecision(symbol, priceTakeProfit));
      const slPrice      = parseFloat(exchange.priceToPrecision(symbol, priceStopLoss));

      // Restore SL/TP on remaining qty if partial close times out so position is not left unprotected
      await createLimitOrderAndWait(exchange, symbol, "sell", qty, closePrice, { tpPrice, slPrice });

      // Restore SL/TP on remaining qty after successful partial close
      if (remainingQty > 0) {
        try {
          await exchange.createOrder(symbol, "limit", "sell", remainingQty, tpPrice);
          await createStopLossOrder(exchange, symbol, remainingQty, slPrice);
        } catch (err) {
          // Remaining position is unprotected — close via market
          await exchange.createOrder(symbol, "market", "sell", remainingQty);
          throw err;
        }
      }
    }

    async onTrailingStopCommit(payload: BrokerTrailingStopPayload): Promise<void> {
      const { symbol, newStopLossPrice } = payload;
      const exchange = await getSpotExchange();

      // Cancel existing SL order only — Spot has no reduceOnly, filter by side + type
      const orders  = await exchange.fetchOpenOrders(symbol);
      const slOrder = orders.find((o) =>
        o.side === "sell" &&
        ["stop_loss_limit", "stop", "STOP_LOSS_LIMIT"].includes(o.type ?? "")
      ) ?? null;
      if (slOrder) {
        await exchange.cancelOrder(slOrder.id, symbol);
        await sleep(CANCEL_SETTLE_MS);
      }

      const qty = truncateQty(exchange, symbol, await fetchFreeQty(exchange, symbol));

      // Position may have already been closed by SL/TP on exchange — skip gracefully
      if (qty === 0) {
        throw new Error(`TrailingStop skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const slPrice = parseFloat(exchange.priceToPrecision(symbol, newStopLossPrice));

      await createStopLossOrder(exchange, symbol, qty, slPrice);
    }

    async onTrailingTakeCommit(payload: BrokerTrailingTakePayload): Promise<void> {
      const { symbol, newTakeProfitPrice } = payload;
      const exchange = await getSpotExchange();

      // Cancel existing TP order only — Spot has no reduceOnly, filter by side + type
      const orders  = await exchange.fetchOpenOrders(symbol);
      const tpOrder = orders.find((o) =>
        o.side === "sell" &&
        ["limit", "LIMIT"].includes(o.type ?? "")
      ) ?? null;
      if (tpOrder) {
        await exchange.cancelOrder(tpOrder.id, symbol);
        await sleep(CANCEL_SETTLE_MS);
      }

      const qty = truncateQty(exchange, symbol, await fetchFreeQty(exchange, symbol));

      // Position may have already been closed by SL/TP on exchange — skip gracefully
      if (qty === 0) {
        throw new Error(`TrailingTake skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const tpPrice = parseFloat(exchange.priceToPrecision(symbol, newTakeProfitPrice));

      await exchange.createOrder(symbol, "limit", "sell", qty, tpPrice);
    }

    async onBreakevenCommit(payload: BrokerBreakevenPayload): Promise<void> {
      const { symbol, newStopLossPrice } = payload;
      const exchange = await getSpotExchange();

      // Cancel existing SL order only — Spot has no reduceOnly, filter by side + type
      const orders  = await exchange.fetchOpenOrders(symbol);
      const slOrder = orders.find((o) =>
        o.side === "sell" &&
        ["stop_loss_limit", "stop", "STOP_LOSS_LIMIT"].includes(o.type ?? "")
      ) ?? null;
      if (slOrder) {
        await exchange.cancelOrder(slOrder.id, symbol);
        await sleep(CANCEL_SETTLE_MS);
      }

      const qty = truncateQty(exchange, symbol, await fetchFreeQty(exchange, symbol));

      // Position may have already been closed by SL/TP on exchange — skip gracefully
      if (qty === 0) {
        throw new Error(`Breakeven skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const slPrice = parseFloat(exchange.priceToPrecision(symbol, newStopLossPrice));

      await createStopLossOrder(exchange, symbol, qty, slPrice);
    }

    async onAverageBuyCommit(payload: BrokerAverageBuyPayload): Promise<void> {
      const { symbol, currentPrice, cost, priceTakeProfit, priceStopLoss } = payload;
      const exchange = await getSpotExchange();

      // Cancel existing SL/TP first — existing check must happen after cancel+settle
      // to avoid race condition where SL/TP fills between the existence check and cancel
      const openOrders = await exchange.fetchOpenOrders(symbol);
      await cancelAllOrders(exchange, openOrders, symbol);
      await sleep(CANCEL_SETTLE_MS);

      // Guard against DCA into a ghost position — checked after cancel so the snapshot is fresh
      const existing    = await fetchFreeQty(exchange, symbol);
      const minNotional = exchange.markets[symbol].limits?.cost?.min ?? 1;

      // Compare notional value rather than raw qty — avoids float === 0 trap
      // and correctly rejects dust balances left over from previous trades
      if (existing * currentPrice < minNotional) {
        throw new Error(`AverageBuy skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const qty = truncateQty(exchange, symbol, cost / currentPrice);

      // Guard: truncation may produce 0 if cost/price is below lot size
      if (qty <= 0) {
        throw new Error(`Computed qty is zero for ${symbol} — cost=${cost}, price=${currentPrice}`);
      }

      const entryPrice = parseFloat(exchange.priceToPrecision(symbol, currentPrice));
      const tpPrice    = parseFloat(exchange.priceToPrecision(symbol, priceTakeProfit));
      const slPrice    = parseFloat(exchange.priceToPrecision(symbol, priceStopLoss));

      // DCA entry: restore SL/TP on existing qty if times out so position is not left unprotected
      await createLimitOrderAndWait(exchange, symbol, "buy", qty, entryPrice, { tpPrice, slPrice });

      // Refetch balance after fill — existing snapshot is stale after cancel + fill
      const totalQty = truncateQty(exchange, symbol, await fetchFreeQty(exchange, symbol));

      // Recreate SL/TP on fresh total qty after successful fill
      try {
        await exchange.createOrder(symbol, "limit", "sell", totalQty, tpPrice);
        await createStopLossOrder(exchange, symbol, totalQty, slPrice);
      } catch (err) {
        // Total position is unprotected — close via market
        await exchange.createOrder(symbol, "market", "sell", totalQty);
        throw err;
      }
    }
  }
);

Broker.enable();

Futures

import ccxt from "ccxt";
import { singleshot, sleep } from "functools-kit";
import {
  Broker,
  IBroker,
  BrokerSignalOpenPayload,
  BrokerSignalClosePayload,
  BrokerPartialProfitPayload,
  BrokerPartialLossPayload,
  BrokerTrailingStopPayload,
  BrokerTrailingTakePayload,
  BrokerBreakevenPayload,
  BrokerAverageBuyPayload,
} from "backtest-kit";

const FILL_POLL_INTERVAL_MS = 10_000;
const FILL_POLL_ATTEMPTS = 10;

/**
 * Sleep between cancelOrder and fetchPositions to allow Binance to settle the
 * cancellation — reads immediately after cancel may return stale data.
 */
const CANCEL_SETTLE_MS = 2_000;

/**
 * 3x leverage — conservative choice for $1000 total fiat.
 * Enough to matter, not enough to liquidate on normal volatility.
 * Applied per-symbol on first open via setLeverage.
 */
const FUTURES_LEVERAGE = 3;

const getFuturesExchange = singleshot(async () => {
  const exchange = new ccxt.binance({
    apiKey: process.env.BINANCE_API_KEY,
    secret: process.env.BINANCE_API_SECRET,
    options: {
      defaultType: "future",
      adjustForTimeDifference: true,
      recvWindow: 60000,
    },
    enableRateLimit: true,
  });
  await exchange.loadMarkets();
  return exchange;
});

/**
 * Truncate qty to exchange precision, always rounding down.
 * Prevents over-selling due to floating point drift from fetchPositions.
 */
function truncateQty(exchange: ccxt.binance, symbol: string, qty: number): number {
  return parseFloat(exchange.amountToPrecision(symbol, qty, exchange.TRUNCATE));
}

/**
 * Resolve position for symbol filtered by side — safe in both one-way and hedge mode.
 */
function findPosition(positions: ccxt.Position[], symbol: string, side: "long" | "short") {
  // Hedge mode: positions have explicit side field
  const hedged = positions.find((p) => p.symbol === symbol && p.side === side);
  if (hedged) {
    return hedged;
  }
  // One-way mode: single position per symbol, side field may be undefined or mismatched
  const pos = positions.find((p) => p.symbol === symbol) ?? null;
  if (pos && pos.side && pos.side !== side) {
    console.warn(`findPosition: expected side="${side}" but exchange returned side="${pos.side}" for ${symbol} — possible one-way/hedge mode mismatch`);
  }
  return pos;
}

/**
 * Fetch current contracts qty for symbol/side.
 */
async function fetchContractsQty(
  exchange: ccxt.binance,
  symbol: string,
  side: "long" | "short"
): Promise<number> {
  const positions = await exchange.fetchPositions([symbol]);
  const pos       = findPosition(positions, symbol, side);
  return Math.abs(parseFloat(String(pos?.contracts ?? 0)));
}

/**
 * Cancel all orders in parallel — allSettled so a single failure (already filled,
 * network blip) does not leave remaining orders uncancelled.
 */
async function cancelAllOrders(exchange: ccxt.binance, orders: ccxt.Order[], symbol: string): Promise<void> {
  await Promise.allSettled(orders.map((o) => exchange.cancelOrder(o.id, symbol)));
}

/**
 * Resolve Binance positionSide string from position direction.
 * Required in hedge mode to correctly route orders; ignored in one-way mode.
 */
function toPositionSide(position: "long" | "short"): "LONG" | "SHORT" {
  return position === "long" ? "LONG" : "SHORT";
}

/**
 * Place a limit order and poll until filled (status === "closed").
 * On timeout: cancel the order, settle, check partial fill and close it via market,
 * restore SL/TP on remaining position so it is never left unprotected, then throw.
 *
 * positionSide is forwarded into rollback market order so hedge mode accounts
 * correctly route the close without -4061 error.
 */
async function createLimitOrderAndWait(
  exchange: ccxt.binance,
  symbol: string,
  side: "buy" | "sell",
  qty: number,
  price: number,
  params: Record<string, unknown> = {},
  restore?: { exitSide: "buy" | "sell"; tpPrice: number; slPrice: number; positionSide: "long" | "short" }
): Promise<void> {
  const order = await exchange.createOrder(symbol, "limit", side, qty, price, params);

  for (let i = 0; i < FILL_POLL_ATTEMPTS; i++) {
    await sleep(FILL_POLL_INTERVAL_MS);
    const status = await exchange.fetchOrder(order.id, symbol);
    if (status.status === "closed") {
      return;
    }
  }

  await exchange.cancelOrder(order.id, symbol);

  // Wait for Binance to settle the cancellation before reading filled qty
  await sleep(CANCEL_SETTLE_MS);

  const final     = await exchange.fetchOrder(order.id, symbol);
  const filledQty = final.filled ?? 0;

  if (filledQty > 0) {
    // Close partial fill via market — positionSide required in hedge mode (-4061 without it)
    const rollbackSide        = side === "buy" ? "sell" : "buy";
    const rollbackPositionSide = params.positionSide ?? (restore ? toPositionSide(restore.positionSide) : undefined);
    await exchange.createOrder(symbol, "market", rollbackSide, filledQty, undefined, {
      reduceOnly: true,
      ...(rollbackPositionSide ? { positionSide: rollbackPositionSide } : {}),
    });
  }

  // Restore SL/TP on remaining position so it is not left unprotected during retry
  if (restore) {
    const remainingQty = truncateQty(exchange, symbol, await fetchContractsQty(exchange, symbol, restore.positionSide));
    if (remainingQty > 0) {
      await exchange.createOrder(symbol, "limit", restore.exitSide, remainingQty, restore.tpPrice, { reduceOnly: true });
      await exchange.createOrder(symbol, "stop_market", restore.exitSide, remainingQty, undefined, { stopPrice: restore.slPrice, reduceOnly: true });
    }
  }

  throw new Error(`Limit order ${order.id} [${side} ${qty} ${symbol} @ ${price}] not filled in time — partial fill rolled back, backtest-kit will retry`);
}

Broker.useBrokerAdapter(
  class implements IBroker {

    async waitForInit(): Promise<void> {
      await getFuturesExchange();
    }

    async onSignalOpenCommit(payload: BrokerSignalOpenPayload): Promise<void> {
      const { symbol, cost, priceOpen, priceTakeProfit, priceStopLoss, position } = payload;
      const exchange = await getFuturesExchange();

      // Set leverage before entry — ensures consistent leverage regardless of previous session state
      await exchange.setLeverage(FUTURES_LEVERAGE, symbol);

      const qty = truncateQty(exchange, symbol, cost / priceOpen);

      // Guard: truncation may produce 0 if cost/price is below lot size
      if (qty <= 0) {
        throw new Error(`Computed qty is zero for ${symbol} — cost=${cost}, price=${priceOpen}`);
      }

      const openPrice    = parseFloat(exchange.priceToPrecision(symbol, priceOpen));
      const tpPrice      = parseFloat(exchange.priceToPrecision(symbol, priceTakeProfit));
      const slPrice      = parseFloat(exchange.priceToPrecision(symbol, priceStopLoss));
      const entrySide    = position === "long" ? "buy"  : "sell";
      const exitSide     = position === "long" ? "sell" : "buy";
      // positionSide required in hedge mode (-4061 without it); ignored in one-way mode
      const positionSide = toPositionSide(position);

      // Entry: no restore needed — position does not exist yet if entry times out
      await createLimitOrderAndWait(exchange, symbol, entrySide, qty, openPrice, { positionSide });

      // Post-fill: if TP/SL placement fails, position is open and unprotected — close via market
      try {
        await exchange.createOrder(symbol, "limit", exitSide, qty, tpPrice, { reduceOnly: true, positionSide });
        await exchange.createOrder(symbol, "stop_market", exitSide, qty, undefined, { stopPrice: slPrice, reduceOnly: true, positionSide });
      } catch (err) {
        await exchange.createOrder(symbol, "market", exitSide, qty, undefined, { reduceOnly: true, positionSide });
        throw err;
      }
    }

    async onSignalCloseCommit(payload: BrokerSignalClosePayload): Promise<void> {
      const { symbol, position, currentPrice, priceTakeProfit, priceStopLoss } = payload;
      const exchange = await getFuturesExchange();

      const openOrders = await exchange.fetchOpenOrders(symbol);
      await cancelAllOrders(exchange, openOrders, symbol);
      await sleep(CANCEL_SETTLE_MS);

      const qty      = truncateQty(exchange, symbol, await fetchContractsQty(exchange, symbol, position));
      const exitSide = position === "long" ? "sell" : "buy";

      // Position already closed by SL/TP on exchange — throw so backtest-kit can reconcile
      // the close price via its own mechanism rather than assuming a successful manual close
      if (qty === 0) {
        throw new Error(`SignalClose skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const closePrice = parseFloat(exchange.priceToPrecision(symbol, currentPrice));
      const tpPrice    = parseFloat(exchange.priceToPrecision(symbol, priceTakeProfit));
      const slPrice    = parseFloat(exchange.priceToPrecision(symbol, priceStopLoss));

      // reduceOnly: prevents accidental reversal if qty has drift vs real position
      // Restore SL/TP if close times out so position is not left unprotected during retry
      await createLimitOrderAndWait(
        exchange, symbol, exitSide, qty, closePrice,
        { reduceOnly: true },
        { exitSide, tpPrice, slPrice, positionSide: position }
      );
    }

    async onPartialProfitCommit(payload: BrokerPartialProfitPayload): Promise<void> {
      const { symbol, percentToClose, currentPrice, position, priceTakeProfit, priceStopLoss } = payload;
      const exchange = await getFuturesExchange();

      const openOrders = await exchange.fetchOpenOrders(symbol);
      await cancelAllOrders(exchange, openOrders, symbol);
      await sleep(CANCEL_SETTLE_MS);

      const totalQty = await fetchContractsQty(exchange, symbol, position);

      // Position may have already been closed by SL/TP on exchange — skip gracefully
      if (totalQty === 0) {
        throw new Error(`PartialProfit skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const qty          = truncateQty(exchange, symbol, totalQty * (percentToClose / 100));
      const remainingQty = truncateQty(exchange, symbol, totalQty - qty);
      const closePrice   = parseFloat(exchange.priceToPrecision(symbol, currentPrice));
      const tpPrice      = parseFloat(exchange.priceToPrecision(symbol, priceTakeProfit));
      const slPrice      = parseFloat(exchange.priceToPrecision(symbol, priceStopLoss));
      const exitSide     = position === "long" ? "sell" : "buy";
      const positionSide = toPositionSide(position);

      // reduceOnly: prevents accidental reversal if qty has drift vs real position
      // Restore SL/TP on remaining qty if partial close times out so position is not left unprotected
      await createLimitOrderAndWait(
        exchange, symbol, exitSide, qty, closePrice,
        { reduceOnly: true },
        { exitSide, tpPrice, slPrice, positionSide: position }
      );

      // Restore SL/TP on remaining qty after successful partial close
      if (remainingQty > 0) {
        try {
          await exchange.createOrder(symbol, "limit", exitSide, remainingQty, tpPrice, { reduceOnly: true, positionSide });
          await exchange.createOrder(symbol, "stop_market", exitSide, remainingQty, undefined, { stopPrice: slPrice, reduceOnly: true, positionSide });
        } catch (err) {
          // Remaining position is unprotected — close via market
          await exchange.createOrder(symbol, "market", exitSide, remainingQty, undefined, { reduceOnly: true, positionSide });
          throw err;
        }
      }
    }

    async onPartialLossCommit(payload: BrokerPartialLossPayload): Promise<void> {
      const { symbol, percentToClose, currentPrice, position, priceTakeProfit, priceStopLoss } = payload;
      const exchange = await getFuturesExchange();

      const openOrders = await exchange.fetchOpenOrders(symbol);
      await cancelAllOrders(exchange, openOrders, symbol);
      await sleep(CANCEL_SETTLE_MS);

      const totalQty = await fetchContractsQty(exchange, symbol, position);

      // Position may have already been closed by SL/TP on exchange — skip gracefully
      if (totalQty === 0) {
        throw new Error(`PartialLoss skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const qty          = truncateQty(exchange, symbol, totalQty * (percentToClose / 100));
      const remainingQty = truncateQty(exchange, symbol, totalQty - qty);
      const closePrice   = parseFloat(exchange.priceToPrecision(symbol, currentPrice));
      const tpPrice      = parseFloat(exchange.priceToPrecision(symbol, priceTakeProfit));
      const slPrice      = parseFloat(exchange.priceToPrecision(symbol, priceStopLoss));
      const exitSide     = position === "long" ? "sell" : "buy";
      const positionSide = toPositionSide(position);

      // reduceOnly: prevents accidental reversal if qty has drift vs real position
      // Restore SL/TP on remaining qty if partial close times out so position is not left unprotected
      await createLimitOrderAndWait(
        exchange, symbol, exitSide, qty, closePrice,
        { reduceOnly: true },
        { exitSide, tpPrice, slPrice, positionSide: position }
      );

      // Restore SL/TP on remaining qty after successful partial close
      if (remainingQty > 0) {
        try {
          await exchange.createOrder(symbol, "limit", exitSide, remainingQty, tpPrice, { reduceOnly: true, positionSide });
          await exchange.createOrder(symbol, "stop_market", exitSide, remainingQty, undefined, { stopPrice: slPrice, reduceOnly: true, positionSide });
        } catch (err) {
          // Remaining position is unprotected — close via market
          await exchange.createOrder(symbol, "market", exitSide, remainingQty, undefined, { reduceOnly: true, positionSide });
          throw err;
        }
      }
    }

    async onTrailingStopCommit(payload: BrokerTrailingStopPayload): Promise<void> {
      const { symbol, newStopLossPrice, position } = payload;
      const exchange = await getFuturesExchange();

      // Cancel existing SL order only — filter by reduceOnly to avoid cancelling unrelated orders
      const orders  = await exchange.fetchOpenOrders(symbol);
      const slOrder = orders.find((o) =>
        !!o.reduceOnly &&
        ["stop_market", "stop", "STOP_MARKET"].includes(o.type ?? "")
      ) ?? null;
      if (slOrder) {
        await exchange.cancelOrder(slOrder.id, symbol);
        await sleep(CANCEL_SETTLE_MS);
      }

      const qty      = truncateQty(exchange, symbol, await fetchContractsQty(exchange, symbol, position));
      const exitSide = position === "long" ? "sell" : "buy";

      // Position may have already been closed by SL/TP on exchange — skip gracefully
      if (qty === 0) {
        throw new Error(`TrailingStop skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const slPrice      = parseFloat(exchange.priceToPrecision(symbol, newStopLossPrice));
      const positionSide = toPositionSide(position);

      // positionSide required in hedge mode (-4061 without it); ignored in one-way mode
      await exchange.createOrder(symbol, "stop_market", exitSide, qty, undefined, { stopPrice: slPrice, reduceOnly: true, positionSide });
    }

    async onTrailingTakeCommit(payload: BrokerTrailingTakePayload): Promise<void> {
      const { symbol, newTakeProfitPrice, position } = payload;
      const exchange = await getFuturesExchange();

      // Cancel existing TP order only — filter by reduceOnly to avoid cancelling unrelated orders
      const orders  = await exchange.fetchOpenOrders(symbol);
      const tpOrder = orders.find((o) =>
        !!o.reduceOnly &&
        ["limit", "LIMIT"].includes(o.type ?? "")
      ) ?? null;
      if (tpOrder) {
        await exchange.cancelOrder(tpOrder.id, symbol);
        await sleep(CANCEL_SETTLE_MS);
      }

      const qty      = truncateQty(exchange, symbol, await fetchContractsQty(exchange, symbol, position));
      const exitSide = position === "long" ? "sell" : "buy";

      // Position may have already been closed by SL/TP on exchange — skip gracefully
      if (qty === 0) {
        throw new Error(`TrailingTake skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const tpPrice      = parseFloat(exchange.priceToPrecision(symbol, newTakeProfitPrice));
      const positionSide = toPositionSide(position);

      // positionSide required in hedge mode (-4061 without it); ignored in one-way mode
      await exchange.createOrder(symbol, "limit", exitSide, qty, tpPrice, { reduceOnly: true, positionSide });
    }

    async onBreakevenCommit(payload: BrokerBreakevenPayload): Promise<void> {
      const { symbol, newStopLossPrice, position } = payload;
      const exchange = await getFuturesExchange();

      // Cancel existing SL order only — filter by reduceOnly to avoid cancelling unrelated orders
      const orders  = await exchange.fetchOpenOrders(symbol);
      const slOrder = orders.find((o) =>
        !!o.reduceOnly &&
        ["stop_market", "stop", "STOP_MARKET"].includes(o.type ?? "")
      ) ?? null;
      if (slOrder) {
        await exchange.cancelOrder(slOrder.id, symbol);
        await sleep(CANCEL_SETTLE_MS);
      }

      const qty      = truncateQty(exchange, symbol, await fetchContractsQty(exchange, symbol, position));
      const exitSide = position === "long" ? "sell" : "buy";

      // Position may have already been closed by SL/TP on exchange — skip gracefully
      if (qty === 0) {
        throw new Error(`Breakeven skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const slPrice      = parseFloat(exchange.priceToPrecision(symbol, newStopLossPrice));
      const positionSide = toPositionSide(position);

      // positionSide required in hedge mode (-4061 without it); ignored in one-way mode
      await exchange.createOrder(symbol, "stop_market", exitSide, qty, undefined, { stopPrice: slPrice, reduceOnly: true, positionSide });
    }

    async onAverageBuyCommit(payload: BrokerAverageBuyPayload): Promise<void> {
      const { symbol, currentPrice, cost, position, priceTakeProfit, priceStopLoss } = payload;
      const exchange = await getFuturesExchange();

      // Cancel existing SL/TP first — existing check must happen after cancel+settle
      // to avoid race condition where SL/TP fills between the existence check and cancel
      const openOrders = await exchange.fetchOpenOrders(symbol);
      await cancelAllOrders(exchange, openOrders, symbol);
      await sleep(CANCEL_SETTLE_MS);

      // Guard against DCA into a ghost position — checked after cancel so the snapshot is fresh
      const existing    = await fetchContractsQty(exchange, symbol, position);
      const minNotional = exchange.markets[symbol].limits?.cost?.min ?? 1;

      // Compare notional value rather than raw contracts — avoids float === 0 trap
      // and correctly rejects dust positions left over from previous trades
      if (existing * currentPrice < minNotional) {
        throw new Error(`AverageBuy skipped: no open position for ${symbol} on exchange — SL/TP may have already been filled`);
      }

      const qty = truncateQty(exchange, symbol, cost / currentPrice);

      // Guard: truncation may produce 0 if cost/price is below lot size
      if (qty <= 0) {
        throw new Error(`Computed qty is zero for ${symbol} — cost=${cost}, price=${currentPrice}`);
      }

      const entryPrice   = parseFloat(exchange.priceToPrecision(symbol, currentPrice));
      const tpPrice      = parseFloat(exchange.priceToPrecision(symbol, priceTakeProfit));
      const slPrice      = parseFloat(exchange.priceToPrecision(symbol, priceStopLoss));
      // positionSide required in hedge mode to add to correct side; ignored in one-way mode
      const positionSide = toPositionSide(position);
      const entrySide    = position === "long" ? "buy"  : "sell";
      const exitSide     = position === "long" ? "sell" : "buy";

      // DCA entry: restore SL/TP on existing qty if times out so position is not left unprotected
      await createLimitOrderAndWait(
        exchange, symbol, entrySide, qty, entryPrice,
        { positionSide },
        { exitSide, tpPrice, slPrice, positionSide: position }
      );

      // Refetch contracts after fill — existing snapshot is stale after cancel + fill
      const totalQty = truncateQty(exchange, symbol, await fetchContractsQty(exchange, symbol, position));

      // Recreate SL/TP on fresh total qty after successful fill
      try {
        await exchange.createOrder(symbol, "limit", exitSide, totalQty, tpPrice, { reduceOnly: true, positionSide });
        await exchange.createOrder(symbol, "stop_market", exitSide, totalQty, undefined, { stopPrice: slPrice, reduceOnly: true, positionSide });
      } catch (err) {
        // Total position is unprotected — close via market
        await exchange.createOrder(symbol, "market", exitSide, totalQty, undefined, { reduceOnly: true, positionSide });
        throw err;
      }
    }
  }
);

Broker.enable();

Signal open/close events are routed automatically via an internal event bus once Broker.enable() is called. No manual wiring needed. All other operations (partialProfit, trailingStop, breakeven, averageBuy) are intercepted explicitly before the corresponding state mutation.

🔍 How getCandles Works

backtest-kit uses Node.js AsyncLocalStorage to automatically provide temporal time context to your strategies.

For a candle with:

• timestamp = candle open time (openTime)
• stepMs = interval duration (e.g., 60000ms for "1m")
• Candle close time = timestamp + stepMs

Alignment: All timestamps are aligned down to interval boundary. For example, for 15m interval: 00:17 → 00:15, 00:44 → 00:30

Adapter contract:

• First candle.timestamp must equal aligned since
• Adapter must return exactly limit candles
• Sequential timestamps: since + i * stepMs for i = 0..limit-1

How since is calculated from when:

• when = current execution context time (from AsyncLocalStorage)
• alignedWhen = Math.floor(when / stepMs) * stepMs (aligned down to interval boundary)
• since = alignedWhen - limit * stepMs (go back limit candles from aligned when)

Boundary semantics (inclusive/exclusive):

• since is always inclusive — first candle has timestamp === since

• Exactly limit candles are returned

• Last candle has timestamp === since + (limit - 1) * stepMs — inclusive

• For getCandles: alignedWhen is exclusive — candle at that timestamp is NOT included (it's a pending/incomplete candle)

• For getRawCandles: eDate is exclusive — candle at that timestamp is NOT included (it's a pending/incomplete candle)

• For getNextCandles: alignedWhen is inclusive — first candle starts at alignedWhen (it's the current candle for backtest, already closed in historical data)

• getCandles(symbol, interval, limit) - Returns exactly limit candles

  • Aligns when down to interval boundary
  • Calculates since = alignedWhen - limit * stepMs
  • since — inclusive, first candle.timestamp === since
  • alignedWhen — exclusive, candle at alignedWhen is NOT returned
  • Range: [since, alignedWhen) — half-open interval
  • Example: getCandles("BTCUSDT", "1m", 100) returns 100 candles ending before aligned when

• getNextCandles(symbol, interval, limit) - Returns exactly limit candles (backtest only)

  • Aligns when down to interval boundary
  • since = alignedWhen (starts from aligned when, going forward)
  • since — inclusive, first candle.timestamp === since
  • Range: [alignedWhen, alignedWhen + limit * stepMs) — half-open interval
  • Throws error in live mode to prevent look-ahead bias
  • Example: getNextCandles("BTCUSDT", "1m", 10) returns next 10 candles starting from aligned when

• getRawCandles(symbol, interval, limit?, sDate?, eDate?) - Flexible parameter combinations:

  • (limit) - since = alignedWhen - limit * stepMs, range [since, alignedWhen)
  • (limit, sDate) - since = align(sDate), returns limit candles forward, range [since, since + limit * stepMs)
  • (limit, undefined, eDate) - since = align(eDate) - limit * stepMs, eDate — exclusive, range [since, eDate)
  • (undefined, sDate, eDate) - since = align(sDate), limit calculated from range, sDate — inclusive, eDate — exclusive, range [sDate, eDate)
  • (limit, sDate, eDate) - since = align(sDate), returns limit candles, sDate — inclusive
  • All combinations respect look-ahead bias protection (eDate/endTime <= when)

Persistent Cache:

• Cache lookup calculates expected timestamps: since + i * stepMs for i = 0..limit-1
• Returns all candles if found, null if any missing (cache miss)
• Cache and runtime use identical timestamp calculation logic

Candle Timestamp Convention:

According to this timestamp of a candle in backtest-kit is exactly the openTime, not ~~closeTime~~

Key principles:

• All timestamps are aligned down to interval boundary
• First candle.timestamp must equal aligned since
• Adapter must return exactly limit candles
• Sequential timestamps: since + i * stepMs

🔍 How getOrderBook Works

Order book fetching uses the same temporal alignment as candles, but with a configurable time offset window instead of candle intervals.

**Time range calculation:**
- `when` = current execution context time (from AsyncLocalStorage)
- `offsetMinutes` = `CC_ORDER_BOOK_TIME_OFFSET_MINUTES` (configurable)
- `alignedTo` = `Math.floor(when / (offsetMinutes * 60000)) * (offsetMinutes * 60000)`
- `to` = `alignedTo` (aligned down to offset boundary)
- `from` = `alignedTo - offsetMinutes * 60000`

**Adapter contract:**
- `getOrderBook(symbol, depth, from, to, backtest)` is called on the exchange schema
- `depth` defaults to `CC_ORDER_BOOK_MAX_DEPTH_LEVELS`
- The `from`/`to` range represents a time window of exactly `offsetMinutes` duration
- Schema implementation may use the time range (backtest) or ignore it (live trading)

**Example with CC_ORDER_BOOK_TIME_OFFSET_MINUTES = 10:**
```
when = 1704067920000       // 2024-01-01 00:12:00 UTC
offsetMinutes = 10
offsetMs = 10 * 60000      // 600000ms

alignedTo = Math.floor(1704067920000 / 600000) * 600000
          = 1704067800000  // 2024-01-01 00:10:00 UTC

to   = 1704067800000       // 00:10:00 UTC
from = 1704067200000       // 00:00:00 UTC
```

Order Book Timestamp Convention:

Unlike candles, most exchanges (e.g. Binance GET /api/v3/depth) only expose the current order book with no historical query support — for backtest you must provide your own snapshot storage.

Key principles:

• Time range is aligned down to CC_ORDER_BOOK_TIME_OFFSET_MINUTES boundary
• to = aligned timestamp, from = to - offsetMinutes * 60000
• depth defaults to CC_ORDER_BOOK_MAX_DEPTH_LEVELS
• Adapter receives (symbol, depth, from, to, backtest) — may ignore from/to in live mode

🔍 How getAggregatedTrades Works

Aggregated trades fetching uses the same look-ahead bias protection as candles - to is always aligned down to the nearest minute boundary so future trades are never visible to the strategy.

Key principles:

• to is always aligned down to the 1-minute boundary — prevents look-ahead bias
• Without limit: returns one full window (CC_AGGREGATED_TRADES_MAX_MINUTES)
• With limit: paginates backwards until collected, then slices to most recent limit
• Adapter receives (symbol, from, to, backtest) — may ignore from/to in live mode

Time range calculation:

• when = current execution context time (from AsyncLocalStorage)
• alignedTo = Math.floor(when / 60000) * 60000 (aligned down to 1-minute boundary)
• windowMs = CC_AGGREGATED_TRADES_MAX_MINUTES * 60000 − 60000
• to = alignedTo, from = alignedTo − windowMs

Without limit: fetches a single window and returns it as-is.

With limit: paginates backwards in CC_AGGREGATED_TRADES_MAX_MINUTES chunks until at least limit trades are collected, then slices to the most recent limit trades.

Example with CC_AGGREGATED_TRADES_MAX_MINUTES = 60, limit = 200:

when       = 1704067920000   // 2024-01-01 00:12:00 UTC
alignedTo  = 1704067800000   // 2024-01-01 00:12:00 → aligned to 00:12:00
windowMs   = 59 * 60000      // 3540000ms = 59 minutes

Window 1:  from = 00:12:00 − 59m = 23:13:00
            to   = 00:12:00
→ got 120 trades — not enough

Window 2:  from = 23:13:00 − 59m = 22:14:00
            to   = 23:13:00
→ got 100 more → total 220 trades

result = last 200 of 220 (most recent)

Adapter contract:

• getAggregatedTrades(symbol, from, to, backtest) is called on the exchange schema
• from/to are Date objects
• Schema implementation may use the time range (backtest) or ignore it (live trading)

Compatible with: garch for volatility modelling and volume-anomaly for detecting abnormal trade volume — both accept the same from/to time range format that getAggregatedTrades produces.

🔬 Technical Details: Timestamp Alignment

Why align timestamps to interval boundaries?

Because candle APIs return data starting from exact interval boundaries:

// 15-minute interval example:
when = 1704067920000       // 00:12:00
step = 15                  // 15 minutes
stepMs = 15 * 60000        // 900000ms

// Alignment: round down to nearest interval boundary
alignedWhen = Math.floor(when / stepMs) * stepMs
// = Math.floor(1704067920000 / 900000) * 900000
// = 1704067200000 (00:00:00)

// Calculate since for 4 candles backwards:
since = alignedWhen - 4 * stepMs
// = 1704067200000 - 4 * 900000
// = 1704063600000 (23:00:00 previous day)

// Expected candles:
// [0] timestamp = 1704063600000 (23:00)
// [1] timestamp = 1704064500000 (23:15)
// [2] timestamp = 1704065400000 (23:30)
// [3] timestamp = 1704066300000 (23:45)

Pending candle exclusion: The candle at 00:00:00 (alignedWhen) is NOT included in the result. At when=00:12:00, this candle covers the period [00:00, 00:15) and is still open (pending). Pending candles have incomplete OHLCV data that would distort technical indicators. Only fully closed candles are returned.

Validation is applied consistently across:

• ✅ getCandles() - validates first timestamp and count
• ✅ getNextCandles() - validates first timestamp and count
• ✅ getRawCandles() - validates first timestamp and count
• ✅ Cache read - calculates exact expected timestamps
• ✅ Cache write - stores validated candles

Result: Deterministic candle retrieval with exact timestamp matching.

🕐 Timezone Warning: Candle Boundaries Are UTC-Based

All candle timestamp alignment uses UTC (Unix epoch). For intervals like 4h, boundaries are 00:00, 04:00, 08:00, 12:00, 16:00, 20:00 UTC. If your local timezone offset is not a multiple of the interval, the since timestamps will look "uneven" in local time.

For example, in UTC+5 the same 4h candle request logs as:

since: Sat Sep 20 2025 13:00:00 GMT+0500  ← looks uneven (13:00)
since: Sat Sep 20 2025 17:00:00 GMT+0500  ← looks uneven (17:00)
since: Sat Sep 20 2025 21:00:00 GMT+0500  ← looks uneven (21:00)
since: Sun Sep 21 2025 05:00:00 GMT+0500  ← looks uneven (05:00)

But in UTC these are perfectly aligned 4h boundaries:

since: Sat, 20 Sep 2025 08:00:00 GMT  ← 08:00 UTC ✓
since: Sat, 20 Sep 2025 12:00:00 GMT  ← 12:00 UTC ✓
since: Sat, 20 Sep 2025 16:00:00 GMT  ← 16:00 UTC ✓
since: Sun, 21 Sep 2025 00:00:00 GMT  ← 00:00 UTC ✓

Use toUTCString() or toISOString() in callbacks to see the actual aligned UTC times.

💭 What this means:

• getCandles() always returns data UP TO the current backtest timestamp using async_hooks
• Multi-timeframe data is automatically synchronized
• Impossible to introduce look-ahead bias - all time boundaries are enforced
• Same code works in both backtest and live modes
• Boundary semantics prevent edge cases in signal generation

🧠 Two Ways to Run the Engine

Backtest Kit exposes the same runtime in two equivalent forms. Both approaches use the same engine and guarantees - only the consumption model differs.

1️⃣ Event-driven (background execution)

Suitable for production bots, monitoring, and long-running processes.

Backtest.background('BTCUSDT', config);

listenSignalBacktest(event => { /* handle signals */ });
listenDoneBacktest(event => { /* finalize / dump report */ });

2️⃣ Async Iterator (pull-based execution)

Suitable for research, scripting, testing, and LLM agents.

for await (const event of Backtest.run('BTCUSDT', config)) {
  // signal | trade | progress | done
}

⚔️ Think of it as...

Open-source QuantConnect/MetaTrader without the vendor lock-in

Unlike cloud-based platforms, backtest-kit runs entirely in your environment. You own the entire stack from data ingestion to live execution. In addition to Ollama, you can use neural-trader in getSignal function or any other third party library

• No C#/C++ required - pure TypeScript/JavaScript
• Self-hosted - your code, your data, your infrastructure
• No platform fees or hidden costs
• Full control over execution and data sources
• GUI for visualization and monitoring

🌍 Ecosystem

The backtest-kit ecosystem extends beyond the core library, offering complementary packages and tools to enhance your trading system development experience:

@backtest-kit/cli

Explore on NPM 📟

The @backtest-kit/cli package is a zero-boilerplate CLI runner for backtest-kit strategies. Point it at your strategy file and run backtests, paper trading, or live bots — no infrastructure code required.

Key Features

• 🚀 Zero Config: Run a backtest with one command — no setup code needed
• 🔄 Three Modes: --backtest, --paper, --live with graceful SIGINT shutdown
• 💾 Auto Cache: Warms OHLCV candle cache for all intervals before the backtest starts
• 🌐 Web Dashboard: Launch @backtest-kit/ui with a single --ui flag
• 📬 **Telegram