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@lacspace/rules

v1.2.0StockKit0 deps

Trading rules as data: a small, safe JSON rule language for "buy when …, sell when …" (price, SMA/EMA, RSI, MACD, ATR, Bollinger, Supertrend direction, N-candle high/low, average volume, % change; above / below / crosses above / crosses below; all/any groups; ATR stop and target), evaluated per candle on OHLCV arrays. Includes a validator that coerces AI-written JSON (no code execution), plain-English descriptions, a next-open backtester (stop-first, costs both sides) and a last-candle screener with sector/price/turnover filters and ranking — all on the same engine. Zero-dependency.

npm i @lacspace/rules
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Usage

rules.ts
import { cleanRules, evaluate, backtestRules, screen, describeRules } from "@lacspace/rules";

const rules = cleanRules({
  name: "EMA cross with RSI filter",
  entry: { mode: "all", conds: [
    { a: { k: "ema", n: 20 }, op: "crossAbove", b: { k: "ema", n: 50 } },
    { a: { k: "rsi", n: 14 }, op: ">", b: { k: "num", v: 50 } },
  ] },
  exit: { mode: "any", conds: [{ a: { k: "ema", n: 20 }, op: "crossBelow", b: { k: "ema", n: 50 } }] },
  stopAtr: 2,
}); // → Rules | null (null when there's no valid entry condition)

describeRules(rules!); // "Buy when EMA 20 crosses above EMA 50 and RSI 14 is above 50; sell when …; stop 2 × ATR below entry."
evaluate(rules!, bars); // { entry: boolean[], exit: boolean[], atr, need }, read on each candle's close

Exports 19

OPERAND_KINDSOPSSTRATEGY_TEMPLATESbacktestRulescleanRulescondToTextdefaultOperanddescribedescribeConddescribeOperanddescribeRulesevaluateoperandSeriesoperandToTextparseRulesrulesStrategyrulesToTextrunBacktestscreen

Keywords

trading-rulesstrategybacktestbacktestingscreenerstock-screener

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