feat: add 19 indicators for external feature-extractor coverage (377 -> 396) (#175)

Adds 19 streaming indicators so an external trading-bot feature extractor can replace its hand-built features with native, batch/streaming-equivalent ones. Each is a real gap (verified against the existing catalogue), production-only, with full Python/Node/WASM bindings, fuzz drivers, and tests. Five commits, one per family group; counter 377 -> 396.

## What's added

**Price Statistics (6)** — `LogReturn`, `RealizedVolatility` (raw quadratic variation, the un-annualised counterpart to `HistoricalVolatility`), `RollingQuantile`, `RollingIqr`, `RollingPercentileRank`, `SpreadAr1Coefficient` (pairwise AR(1) rho of the spread; complements `OuHalfLife`).

**Price Action (4)** — `CloseVsOpen`, `BodySizePct`, `WickRatio`, `HighLowRange` (stateless per-bar OHLC transforms).

**Regime / Trend / Jump labels (3)** — `TrendLabel` (sign of the rolling OLS slope), `JumpIndicator` (return outliers vs trailing volatility, measured as deviation from the trailing mean so steady drift is not flagged), `RegimeLabel` (volatility-quantile regime split).

**Risk / Performance (2)** — `WinRate`, `Expectancy` (R-multiple).

**Microstructure (4)** — `OrderFlowImbalance` (Cont-Kukanov-Stoikov OFI), `Vpin`, `AmihudIlliquidity`, `RollMeasure`. These reuse the existing `OrderBook` / `Trade` inputs (no new input type).

## Intentionally NOT added (already present, would be duplicates)

- **Population skew / kurtosis** — `skewness.rs` / `kurtosis.rs` are already population moments (divisor n).
- **Hurst R/S** — `hurst_exponent.rs` already uses rescaled-range (R/S) analysis.
- **Queue Imbalance** — exactly `OrderBookImbalanceTop1` ((bidSize - askSize) / (bidSize + askSize)).

## Verification

`cargo test -p wickra-core` (lib 3187 + doc 354), `cargo clippy --workspace --all-targets --all-features -D warnings` clean, node `npm run build && npm test` (471), python `pytest` (784). Counter consistent across `mod.rs`, lib block, README, and docs/README at 396.

bindings/node/__tests__/indicators.test.js

@@ -28,6 +28,16 @@ function num(v) {
 // --- Scalar indicators: update(value) vs batch(prices) ---
 
 const scalarFactories = {
+  Expectancy: () => new wickra.Expectancy(20),
+  WinRate: () => new wickra.WinRate(20),
+  RegimeLabel: () => new wickra.RegimeLabel(5, 20),
+  JumpIndicator: () => new wickra.JumpIndicator(20, 3.0),
+  TrendLabel: () => new wickra.TrendLabel(10),
+  RollingQuantile: () => new wickra.RollingQuantile(20, 0.5),
+  RollingPercentileRank: () => new wickra.RollingPercentileRank(14),
+  RollingIqr: () => new wickra.RollingIqr(14),
+  RealizedVolatility: () => new wickra.RealizedVolatility(20),
+  LogReturn: () => new wickra.LogReturn(1),
   TSF: () => new wickra.TSF(14),
   LINEARREG_INTERCEPT: () => new wickra.LINEARREG_INTERCEPT(14),
   ROCR100: () => new wickra.ROCR100(10),
@@ -313,6 +323,10 @@ const candleScalar = {
   Shark: { make: () => new wickra.Shark(), step: (ind, i) => ind.update(open[i], high[i], low[i], close[i]), batch: (ind) => ind.batch(open, high, low, close) },
   Cypher: { make: () => new wickra.Cypher(), step: (ind, i) => ind.update(open[i], high[i], low[i], close[i]), batch: (ind) => ind.batch(open, high, low, close) },
   ThreeDrives: { make: () => new wickra.ThreeDrives(), step: (ind, i) => ind.update(open[i], high[i], low[i], close[i]), batch: (ind) => ind.batch(open, high, low, close) },
+  CloseVsOpen: { make: () => new wickra.CloseVsOpen(), step: (ind, i) => ind.update(open[i], high[i], low[i], close[i]), batch: (ind) => ind.batch(open, high, low, close) },
+  BodySizePct: { make: () => new wickra.BodySizePct(), step: (ind, i) => ind.update(open[i], high[i], low[i], close[i]), batch: (ind) => ind.batch(open, high, low, close) },
+  WickRatio: { make: () => new wickra.WickRatio(), step: (ind, i) => ind.update(open[i], high[i], low[i], close[i]), batch: (ind) => ind.batch(open, high, low, close) },
+  HighLowRange: { make: () => new wickra.HighLowRange(), step: (ind, i) => ind.update(open[i], high[i], low[i], close[i]), batch: (ind) => ind.batch(open, high, low, close) },
 };
 
 for (const [name, d] of Object.entries(candleScalar)) {
@@ -563,6 +577,7 @@ const pairFactories = {
   BetaNeutralSpread: () => new wickra.BetaNeutralSpread(20),
   VarianceRatio: () => new wickra.VarianceRatio(60, 2),
   GrangerCausality: () => new wickra.GrangerCausality(60, 1),
+  SpreadAr1Coefficient: () => new wickra.SpreadAr1Coefficient(40),
 };
 
 for (const [name, make] of Object.entries(pairFactories)) {
@@ -1126,6 +1141,57 @@ test('trade-flow rejects bad input', () => {
   assert.throws(() => new wickra.SignedVolume().update(100, -1, true));
 });
 
+test('order-flow imbalance reference + streaming matches batch', () => {
+  // Rising bid (px up, size 6) with an unchanged ask -> +6 flow.
+  const ofi = new wickra.OrderFlowImbalance(1);
+  assert.equal(ofi.update([100], [5], [101], [4]), null); // seeds the reference
+  assert.ok(Math.abs(ofi.update([100.5], [6], [101], [4]) - 6.0) < 1e-12);
+  const snaps = Array.from({ length: 30 }, (_, i) => ({
+    bidPx: [100 + Math.sin(i * 0.3)],
+    bidSz: [5 + Math.abs(Math.cos(i * 0.5))],
+    askPx: [101 + Math.sin(i * 0.3)],
+    askSz: [4 + Math.abs(Math.sin(i * 0.4))],
+  }));
+  const batch = new wickra.OrderFlowImbalance(10).batch(snaps);
+  const streamer = new wickra.OrderFlowImbalance(10);
+  assert.equal(batch.length, snaps.length);
+  for (let i = 0; i < snaps.length; i++) {
+    const s = streamer.update(snaps[i].bidPx, snaps[i].bidSz, snaps[i].askPx, snaps[i].askSz);
+    assert.ok((Number.isNaN(batch[i]) && s === null) || Math.abs(s - batch[i]) < 1e-9, `mismatch at ${i}`);
+  }
+});
+
+test('vpin / amihud / roll reference + streaming matches batch', () => {
+  // VPIN: two pure-buy buckets of size 10 -> imbalance == size -> 1.
+  const v = new wickra.Vpin(10, 2);
+  let last;
+  for (let i = 0; i < 4; i++) last = v.update(100, 5, true);
+  assert.equal(last, 1.0);
+  // Amihud(1): |ln(101/100)| / (101 * 10).
+  const a = new wickra.AmihudIlliquidity(1);
+  assert.equal(a.update(100, 10, true), null);
+  assert.ok(Math.abs(a.update(101, 10, true) - Math.abs(Math.log(101 / 100)) / (101 * 10)) < 1e-15);
+  // Roll(6): a clean bid-ask bounce of ±1 implies a spread of 2.
+  const r = new wickra.RollMeasure(6);
+  let roll = null;
+  for (let i = 0; i < 20; i++) roll = r.update(i % 2 === 0 ? 100 : 101, 1, true);
+  assert.ok(Math.abs(roll - 2.0) < 1e-12);
+  // Streaming-vs-batch for the three trade-input indicators.
+  const n = 40;
+  const price = Array.from({ length: n }, (_, i) => 100 + Math.sin(i * 0.25) * 4);
+  const size = Array.from({ length: n }, (_, i) => 1 + (i % 5));
+  const isBuy = Array.from({ length: n }, (_, i) => i % 2 === 0);
+  for (const make of [() => new wickra.Vpin(8, 5), () => new wickra.AmihudIlliquidity(14), () => new wickra.RollMeasure(14)]) {
+    const batch = make().batch(price, size, isBuy);
+    const streamer = make();
+    assert.equal(batch.length, n);
+    for (let i = 0; i < n; i++) {
+      const s = streamer.update(price[i], size[i], isBuy[i]);
+      assert.ok((Number.isNaN(batch[i]) && s === null) || Math.abs(s - batch[i]) < 1e-9, `mismatch at ${i}`);
+    }
+  }
+});
+
 test('price-impact indicators reference values', () => {
   // Buy at 100.05 vs mid 100.0: 2 * (100.05 - 100) / 100 * 10000 = 10 bps.
   assert.ok(Math.abs(new wickra.EffectiveSpread().update(100.05, 1, true, 100.0) - 10.0) < 1e-9);

bindings/node/index.d.ts

@@ -809,6 +809,96 @@ export declare class TSF {
   isReady(): boolean
   warmupPeriod(): number
 }
+export type LogReturnNode = LogReturn
+export declare class LogReturn {
+  constructor(period: number)
+  update(value: number): number | null
+  batch(prices: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type RealizedVolatilityNode = RealizedVolatility
+export declare class RealizedVolatility {
+  constructor(period: number)
+  update(value: number): number | null
+  batch(prices: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type RollingIqrNode = RollingIqr
+export declare class RollingIqr {
+  constructor(period: number)
+  update(value: number): number | null
+  batch(prices: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type RollingPercentileRankNode = RollingPercentileRank
+export declare class RollingPercentileRank {
+  constructor(period: number)
+  update(value: number): number | null
+  batch(prices: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type TrendLabelNode = TrendLabel
+export declare class TrendLabel {
+  constructor(period: number)
+  update(value: number): number | null
+  batch(prices: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type WinRateNode = WinRate
+export declare class WinRate {
+  constructor(period: number)
+  update(value: number): number | null
+  batch(prices: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type ExpectancyNode = Expectancy
+export declare class Expectancy {
+  constructor(period: number)
+  update(value: number): number | null
+  batch(prices: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type JumpIndicatorNode = JumpIndicator
+export declare class JumpIndicator {
+  constructor(period: number, threshold: number)
+  update(value: number): number | null
+  batch(prices: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type RegimeLabelNode = RegimeLabel
+export declare class RegimeLabel {
+  constructor(volPeriod: number, lookback: number)
+  update(value: number): number | null
+  batch(prices: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type RollingQuantileNode = RollingQuantile
+export declare class RollingQuantile {
+  constructor(period: number, quantile: number)
+  update(value: number): number | null
+  batch(prices: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
 export type AutocorrelationNode = Autocorrelation
 export declare class Autocorrelation {
   constructor(period: number, lag: number)
@@ -866,6 +956,19 @@ export declare class PairwiseBeta {
   isReady(): boolean
   warmupPeriod(): number
 }
+export type SpreadAr1CoefficientNode = SpreadAr1Coefficient
+export declare class SpreadAr1Coefficient {
+  constructor(period: number)
+  update(x: number, y: number): number | null
+  /**
+   * Batch over two equally-sized arrays. Returns a length-`n` array
+   * with `NaN` for warmup positions.
+   */
+  batch(x: Array<number>, y: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
 export type SpearmanCorrelationNode = SpearmanCorrelation
 export declare class SpearmanCorrelation {
   constructor(period: number)
@@ -1230,6 +1333,42 @@ export declare class HT_PHASOR {
   isReady(): boolean
   warmupPeriod(): number
 }
+export type CloseVsOpenNode = CloseVsOpen
+export declare class CloseVsOpen {
+  constructor()
+  update(open: number, high: number, low: number, close: number): number | null
+  batch(open: Array<number>, high: Array<number>, low: Array<number>, close: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type BodySizePctNode = BodySizePct
+export declare class BodySizePct {
+  constructor()
+  update(open: number, high: number, low: number, close: number): number | null
+  batch(open: Array<number>, high: Array<number>, low: Array<number>, close: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type WickRatioNode = WickRatio
+export declare class WickRatio {
+  constructor()
+  update(open: number, high: number, low: number, close: number): number | null
+  batch(open: Array<number>, high: Array<number>, low: Array<number>, close: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type HighLowRangeNode = HighLowRange
+export declare class HighLowRange {
+  constructor()
+  update(open: number, high: number, low: number, close: number): number | null
+  batch(open: Array<number>, high: Array<number>, low: Array<number>, close: Array<number>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
 export type StochNode = Stochastic
 export declare class Stochastic {
   constructor(kPeriod: number, dPeriod: number)
@@ -3317,6 +3456,42 @@ export declare class TradeImbalance {
   isReady(): boolean
   warmupPeriod(): number
 }
+export type OrderFlowImbalanceNode = OrderFlowImbalance
+export declare class OrderFlowImbalance {
+  constructor(period: number)
+  update(bidPx: Array<number>, bidSz: Array<number>, askPx: Array<number>, askSz: Array<number>): number | null
+  batch(snapshots: Array<ObSnapshot>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type VpinNode = Vpin
+export declare class Vpin {
+  constructor(bucketVolume: number, numBuckets: number)
+  update(price: number, size: number, isBuy: boolean): number | null
+  batch(price: Array<number>, size: Array<number>, isBuy: Array<boolean>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type AmihudIlliquidityNode = AmihudIlliquidity
+export declare class AmihudIlliquidity {
+  constructor(period: number)
+  update(price: number, size: number, isBuy: boolean): number | null
+  batch(price: Array<number>, size: Array<number>, isBuy: Array<boolean>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
+export type RollMeasureNode = RollMeasure
+export declare class RollMeasure {
+  constructor(period: number)
+  update(price: number, size: number, isBuy: boolean): number | null
+  batch(price: Array<number>, size: Array<number>, isBuy: Array<boolean>): Array<number>
+  reset(): void
+  isReady(): boolean
+  warmupPeriod(): number
+}
 export type EffectiveSpreadNode = EffectiveSpread
 export declare class EffectiveSpread {
   constructor()

bindings/node/src/lib.rs

@@ -182,6 +182,125 @@ node_scalar_indicator!(
     wc::LinRegIntercept
 );
 node_scalar_indicator!(TsfNode, "TSF", wc::Tsf);
+node_scalar_indicator!(LogReturnNode, "LogReturn", wc::LogReturn);
+node_scalar_indicator!(
+    RealizedVolatilityNode,
+    "RealizedVolatility",
+    wc::RealizedVolatility
+);
+node_scalar_indicator!(RollingIqrNode, "RollingIqr", wc::RollingIqr);
+node_scalar_indicator!(
+    RollingPercentileRankNode,
+    "RollingPercentileRank",
+    wc::RollingPercentileRank
+);
+node_scalar_indicator!(TrendLabelNode, "TrendLabel", wc::TrendLabel);
+node_scalar_indicator!(WinRateNode, "WinRate", wc::WinRate);
+node_scalar_indicator!(ExpectancyNode, "Expectancy", wc::Expectancy);
+#[napi(js_name = "JumpIndicator")]
+pub struct JumpIndicatorNode {
+    inner: wc::JumpIndicator,
+}
+
+#[napi]
+impl JumpIndicatorNode {
+    #[napi(constructor)]
+    pub fn new(period: u32, threshold: f64) -> napi::Result<Self> {
+        Ok(Self {
+            inner: wc::JumpIndicator::new(period as usize, threshold).map_err(map_err)?,
+        })
+    }
+    #[napi]
+    pub fn update(&mut self, value: f64) -> Option<f64> {
+        self.inner.update(value)
+    }
+    #[napi]
+    pub fn batch(&mut self, prices: Vec<f64>) -> Vec<f64> {
+        flatten(self.inner.batch(&prices))
+    }
+    #[napi]
+    pub fn reset(&mut self) {
+        self.inner.reset();
+    }
+    #[napi(js_name = "isReady")]
+    pub fn is_ready(&self) -> bool {
+        self.inner.is_ready()
+    }
+    #[napi(js_name = "warmupPeriod")]
+    pub fn warmup_period(&self) -> u32 {
+        self.inner.warmup_period() as u32
+    }
+}
+
+#[napi(js_name = "RegimeLabel")]
+pub struct RegimeLabelNode {
+    inner: wc::RegimeLabel,
+}
+
+#[napi]
+impl RegimeLabelNode {
+    #[napi(constructor)]
+    pub fn new(vol_period: u32, lookback: u32) -> napi::Result<Self> {
+        Ok(Self {
+            inner: wc::RegimeLabel::new(vol_period as usize, lookback as usize).map_err(map_err)?,
+        })
+    }
+    #[napi]
+    pub fn update(&mut self, value: f64) -> Option<f64> {
+        self.inner.update(value)
+    }
+    #[napi]
+    pub fn batch(&mut self, prices: Vec<f64>) -> Vec<f64> {
+        flatten(self.inner.batch(&prices))
+    }
+    #[napi]
+    pub fn reset(&mut self) {
+        self.inner.reset();
+    }
+    #[napi(js_name = "isReady")]
+    pub fn is_ready(&self) -> bool {
+        self.inner.is_ready()
+    }
+    #[napi(js_name = "warmupPeriod")]
+    pub fn warmup_period(&self) -> u32 {
+        self.inner.warmup_period() as u32
+    }
+}
+
+#[napi(js_name = "RollingQuantile")]
+pub struct RollingQuantileNode {
+    inner: wc::RollingQuantile,
+}
+
+#[napi]
+impl RollingQuantileNode {
+    #[napi(constructor)]
+    pub fn new(period: u32, quantile: f64) -> napi::Result<Self> {
+        Ok(Self {
+            inner: wc::RollingQuantile::new(period as usize, quantile).map_err(map_err)?,
+        })
+    }
+    #[napi]
+    pub fn update(&mut self, value: f64) -> Option<f64> {
+        self.inner.update(value)
+    }
+    #[napi]
+    pub fn batch(&mut self, prices: Vec<f64>) -> Vec<f64> {
+        flatten(self.inner.batch(&prices))
+    }
+    #[napi]
+    pub fn reset(&mut self) {
+        self.inner.reset();
+    }
+    #[napi(js_name = "isReady")]
+    pub fn is_ready(&self) -> bool {
+        self.inner.is_ready()
+    }
+    #[napi(js_name = "warmupPeriod")]
+    pub fn warmup_period(&self) -> u32 {
+        self.inner.warmup_period() as u32
+    }
+}
 
 // ============================== Autocorrelation (period + lag) ==============================
 
@@ -317,6 +436,11 @@ node_pair_indicator!(
 );
 node_pair_indicator!(BetaNode, "Beta", wc::Beta);
 node_pair_indicator!(PairwiseBetaNode, "PairwiseBeta", wc::PairwiseBeta);
+node_pair_indicator!(
+    SpreadAr1CoefficientNode,
+    "SpreadAr1Coefficient",
+    wc::SpreadAr1Coefficient
+);
 node_pair_indicator!(
     SpearmanCorrelationNode,
     "SpearmanCorrelation",
@@ -1658,6 +1782,266 @@ impl HtPhasorNode {
     }
 }
 
+#[napi(js_name = "CloseVsOpen")]
+pub struct CloseVsOpenNode {
+    inner: wc::CloseVsOpen,
+}
+
+impl Default for CloseVsOpenNode {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+#[napi]
+impl CloseVsOpenNode {
+    #[napi(constructor)]
+    pub fn new() -> Self {
+        Self {
+            inner: wc::CloseVsOpen::new(),
+        }
+    }
+    #[napi]
+    pub fn update(
+        &mut self,
+        open: f64,
+        high: f64,
+        low: f64,
+        close: f64,
+    ) -> napi::Result<Option<f64>> {
+        let candle = wc::Candle::new(open, high, low, close, 0.0, 0).map_err(map_err)?;
+        Ok(self.inner.update(candle))
+    }
+    #[napi]
+    pub fn batch(
+        &mut self,
+        open: Vec<f64>,
+        high: Vec<f64>,
+        low: Vec<f64>,
+        close: Vec<f64>,
+    ) -> napi::Result<Vec<f64>> {
+        if open.len() != high.len() || high.len() != low.len() || low.len() != close.len() {
+            return Err(NapiError::from_reason(
+                "open, high, low, close must be equal length".to_string(),
+            ));
+        }
+        let mut out = Vec::with_capacity(open.len());
+        for i in 0..open.len() {
+            let candle =
+                wc::Candle::new(open[i], high[i], low[i], close[i], 0.0, 0).map_err(map_err)?;
+            out.push(self.inner.update(candle).unwrap_or(f64::NAN));
+        }
+        Ok(out)
+    }
+    #[napi]
+    pub fn reset(&mut self) {
+        self.inner.reset();
+    }
+    #[napi(js_name = "isReady")]
+    pub fn is_ready(&self) -> bool {
+        self.inner.is_ready()
+    }
+    #[napi(js_name = "warmupPeriod")]
+    pub fn warmup_period(&self) -> u32 {
+        self.inner.warmup_period() as u32
+    }
+}
+
+#[napi(js_name = "BodySizePct")]
+pub struct BodySizePctNode {
+    inner: wc::BodySizePct,
+}
+
+impl Default for BodySizePctNode {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+#[napi]
+impl BodySizePctNode {
+    #[napi(constructor)]
+    pub fn new() -> Self {
+        Self {
+            inner: wc::BodySizePct::new(),
+        }
+    }
+    #[napi]
+    pub fn update(
+        &mut self,
+        open: f64,
+        high: f64,
+        low: f64,
+        close: f64,
+    ) -> napi::Result<Option<f64>> {
+        let candle = wc::Candle::new(open, high, low, close, 0.0, 0).map_err(map_err)?;
+        Ok(self.inner.update(candle))
+    }
+    #[napi]
+    pub fn batch(
+        &mut self,
+        open: Vec<f64>,
+        high: Vec<f64>,
+        low: Vec<f64>,
+        close: Vec<f64>,
+    ) -> napi::Result<Vec<f64>> {
+        if open.len() != high.len() || high.len() != low.len() || low.len() != close.len() {
+            return Err(NapiError::from_reason(
+                "open, high, low, close must be equal length".to_string(),
+            ));
+        }
+        let mut out = Vec::with_capacity(open.len());
+        for i in 0..open.len() {
+            let candle =
+                wc::Candle::new(open[i], high[i], low[i], close[i], 0.0, 0).map_err(map_err)?;
+            out.push(self.inner.update(candle).unwrap_or(f64::NAN));
+        }
+        Ok(out)
+    }
+    #[napi]
+    pub fn reset(&mut self) {
+        self.inner.reset();
+    }
+    #[napi(js_name = "isReady")]
+    pub fn is_ready(&self) -> bool {
+        self.inner.is_ready()
+    }
+    #[napi(js_name = "warmupPeriod")]
+    pub fn warmup_period(&self) -> u32 {
+        self.inner.warmup_period() as u32
+    }
+}
+
+#[napi(js_name = "WickRatio")]
+pub struct WickRatioNode {
+    inner: wc::WickRatio,
+}
+
+impl Default for WickRatioNode {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+#[napi]
+impl WickRatioNode {
+    #[napi(constructor)]
+    pub fn new() -> Self {
+        Self {
+            inner: wc::WickRatio::new(),
+        }
+    }
+    #[napi]
+    pub fn update(
+        &mut self,
+        open: f64,
+        high: f64,
+        low: f64,
+        close: f64,
+    ) -> napi::Result<Option<f64>> {
+        let candle = wc::Candle::new(open, high, low, close, 0.0, 0).map_err(map_err)?;
+        Ok(self.inner.update(candle))
+    }
+    #[napi]
+    pub fn batch(
+        &mut self,
+        open: Vec<f64>,
+        high: Vec<f64>,
+        low: Vec<f64>,
+        close: Vec<f64>,
+    ) -> napi::Result<Vec<f64>> {
+        if open.len() != high.len() || high.len() != low.len() || low.len() != close.len() {
+            return Err(NapiError::from_reason(
+                "open, high, low, close must be equal length".to_string(),
+            ));
+        }
+        let mut out = Vec::with_capacity(open.len());
+        for i in 0..open.len() {
+            let candle =
+                wc::Candle::new(open[i], high[i], low[i], close[i], 0.0, 0).map_err(map_err)?;
+            out.push(self.inner.update(candle).unwrap_or(f64::NAN));
+        }
+        Ok(out)
+    }
+    #[napi]
+    pub fn reset(&mut self) {
+        self.inner.reset();
+    }
+    #[napi(js_name = "isReady")]
+    pub fn is_ready(&self) -> bool {
+        self.inner.is_ready()
+    }
+    #[napi(js_name = "warmupPeriod")]
+    pub fn warmup_period(&self) -> u32 {
+        self.inner.warmup_period() as u32
+    }
+}
+
+#[napi(js_name = "HighLowRange")]
+pub struct HighLowRangeNode {
+    inner: wc::HighLowRange,
+}
+
+impl Default for HighLowRangeNode {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+#[napi]
+impl HighLowRangeNode {
+    #[napi(constructor)]
+    pub fn new() -> Self {
+        Self {
+            inner: wc::HighLowRange::new(),
+        }
+    }
+    #[napi]
+    pub fn update(
+        &mut self,
+        open: f64,
+        high: f64,
+        low: f64,
+        close: f64,
+    ) -> napi::Result<Option<f64>> {
+        let candle = wc::Candle::new(open, high, low, close, 0.0, 0).map_err(map_err)?;
+        Ok(self.inner.update(candle))
+    }
+    #[napi]
+    pub fn batch(
+        &mut self,
+        open: Vec<f64>,
+        high: Vec<f64>,
+        low: Vec<f64>,
+        close: Vec<f64>,
+    ) -> napi::Result<Vec<f64>> {
+        if open.len() != high.len() || high.len() != low.len() || low.len() != close.len() {
+            return Err(NapiError::from_reason(
+                "open, high, low, close must be equal length".to_string(),
+            ));
+        }
+        let mut out = Vec::with_capacity(open.len());
+        for i in 0..open.len() {
+            let candle =
+                wc::Candle::new(open[i], high[i], low[i], close[i], 0.0, 0).map_err(map_err)?;
+            out.push(self.inner.update(candle).unwrap_or(f64::NAN));
+        }
+        Ok(out)
+    }
+    #[napi]
+    pub fn reset(&mut self) {
+        self.inner.reset();
+    }
+    #[napi(js_name = "isReady")]
+    pub fn is_ready(&self) -> bool {
+        self.inner.is_ready()
+    }
+    #[napi(js_name = "warmupPeriod")]
+    pub fn warmup_period(&self) -> u32 {
+        self.inner.warmup_period() as u32
+    }
+}
+
 #[napi(object)]
 pub struct StochValue {
     pub k: f64,
@@ -10334,6 +10718,207 @@ impl TradeImbalanceNode {
     }
 }
 
+// Order Flow Imbalance: order-book input with a `period` parameter.
+#[napi(js_name = "OrderFlowImbalance")]
+pub struct OrderFlowImbalanceNode {
+    inner: wc::OrderFlowImbalance,
+}
+
+#[napi]
+impl OrderFlowImbalanceNode {
+    #[napi(constructor)]
+    pub fn new(period: u32) -> napi::Result<Self> {
+        Ok(Self {
+            inner: wc::OrderFlowImbalance::new(period as usize).map_err(map_err)?,
+        })
+    }
+    #[napi]
+    pub fn update(
+        &mut self,
+        bid_px: Vec<f64>,
+        bid_sz: Vec<f64>,
+        ask_px: Vec<f64>,
+        ask_sz: Vec<f64>,
+    ) -> napi::Result<Option<f64>> {
+        let book = build_order_book(&bid_px, &bid_sz, &ask_px, &ask_sz)?;
+        Ok(self.inner.update(book))
+    }
+    #[napi]
+    pub fn batch(&mut self, snapshots: Vec<ObSnapshot>) -> napi::Result<Vec<f64>> {
+        let mut out = Vec::with_capacity(snapshots.len());
+        for snap in &snapshots {
+            let book = build_order_book(&snap.bid_px, &snap.bid_sz, &snap.ask_px, &snap.ask_sz)?;
+            out.push(self.inner.update(book).unwrap_or(f64::NAN));
+        }
+        Ok(out)
+    }
+    #[napi]
+    pub fn reset(&mut self) {
+        self.inner.reset();
+    }
+    #[napi(js_name = "isReady")]
+    pub fn is_ready(&self) -> bool {
+        self.inner.is_ready()
+    }
+    #[napi(js_name = "warmupPeriod")]
+    pub fn warmup_period(&self) -> u32 {
+        self.inner.warmup_period() as u32
+    }
+}
+
+// VPIN: trade input, volume-bucketed `(bucket_volume, num_buckets)`.
+#[napi(js_name = "Vpin")]
+pub struct VpinNode {
+    inner: wc::Vpin,
+}
+
+#[napi]
+impl VpinNode {
+    #[napi(constructor)]
+    pub fn new(bucket_volume: f64, num_buckets: u32) -> napi::Result<Self> {
+        Ok(Self {
+            inner: wc::Vpin::new(bucket_volume, num_buckets as usize).map_err(map_err)?,
+        })
+    }
+    #[napi]
+    pub fn update(&mut self, price: f64, size: f64, is_buy: bool) -> napi::Result<Option<f64>> {
+        Ok(self.inner.update(build_trade(price, size, is_buy)?))
+    }
+    #[napi]
+    pub fn batch(
+        &mut self,
+        price: Vec<f64>,
+        size: Vec<f64>,
+        is_buy: Vec<bool>,
+    ) -> napi::Result<Vec<f64>> {
+        if price.len() != size.len() || size.len() != is_buy.len() {
+            return Err(NapiError::from_reason(
+                "price, size, is_buy must be equal length".to_string(),
+            ));
+        }
+        let mut out = Vec::with_capacity(price.len());
+        for i in 0..price.len() {
+            let trade = build_trade(price[i], size[i], is_buy[i])?;
+            out.push(self.inner.update(trade).unwrap_or(f64::NAN));
+        }
+        Ok(out)
+    }
+    #[napi]
+    pub fn reset(&mut self) {
+        self.inner.reset();
+    }
+    #[napi(js_name = "isReady")]
+    pub fn is_ready(&self) -> bool {
+        self.inner.is_ready()
+    }
+    #[napi(js_name = "warmupPeriod")]
+    pub fn warmup_period(&self) -> u32 {
+        self.inner.warmup_period() as u32
+    }
+}
+
+// Amihud Illiquidity: trade input with a `period` parameter.
+#[napi(js_name = "AmihudIlliquidity")]
+pub struct AmihudIlliquidityNode {
+    inner: wc::AmihudIlliquidity,
+}
+
+#[napi]
+impl AmihudIlliquidityNode {
+    #[napi(constructor)]
+    pub fn new(period: u32) -> napi::Result<Self> {
+        Ok(Self {
+            inner: wc::AmihudIlliquidity::new(period as usize).map_err(map_err)?,
+        })
+    }
+    #[napi]
+    pub fn update(&mut self, price: f64, size: f64, is_buy: bool) -> napi::Result<Option<f64>> {
+        Ok(self.inner.update(build_trade(price, size, is_buy)?))
+    }
+    #[napi]
+    pub fn batch(
+        &mut self,
+        price: Vec<f64>,
+        size: Vec<f64>,
+        is_buy: Vec<bool>,
+    ) -> napi::Result<Vec<f64>> {
+        if price.len() != size.len() || size.len() != is_buy.len() {
+            return Err(NapiError::from_reason(
+                "price, size, is_buy must be equal length".to_string(),
+            ));
+        }
+        let mut out = Vec::with_capacity(price.len());
+        for i in 0..price.len() {
+            let trade = build_trade(price[i], size[i], is_buy[i])?;
+            out.push(self.inner.update(trade).unwrap_or(f64::NAN));
+        }
+        Ok(out)
+    }
+    #[napi]
+    pub fn reset(&mut self) {
+        self.inner.reset();
+    }
+    #[napi(js_name = "isReady")]
+    pub fn is_ready(&self) -> bool {
+        self.inner.is_ready()
+    }
+    #[napi(js_name = "warmupPeriod")]
+    pub fn warmup_period(&self) -> u32 {
+        self.inner.warmup_period() as u32
+    }
+}
+
+// Roll Measure: trade input with a `period` parameter.
+#[napi(js_name = "RollMeasure")]
+pub struct RollMeasureNode {
+    inner: wc::RollMeasure,
+}
+
+#[napi]
+impl RollMeasureNode {
+    #[napi(constructor)]
+    pub fn new(period: u32) -> napi::Result<Self> {
+        Ok(Self {
+            inner: wc::RollMeasure::new(period as usize).map_err(map_err)?,
+        })
+    }
+    #[napi]
+    pub fn update(&mut self, price: f64, size: f64, is_buy: bool) -> napi::Result<Option<f64>> {
+        Ok(self.inner.update(build_trade(price, size, is_buy)?))
+    }
+    #[napi]
+    pub fn batch(
+        &mut self,
+        price: Vec<f64>,
+        size: Vec<f64>,
+        is_buy: Vec<bool>,
+    ) -> napi::Result<Vec<f64>> {
+        if price.len() != size.len() || size.len() != is_buy.len() {
+            return Err(NapiError::from_reason(
+                "price, size, is_buy must be equal length".to_string(),
+            ));
+        }
+        let mut out = Vec::with_capacity(price.len());
+        for i in 0..price.len() {
+            let trade = build_trade(price[i], size[i], is_buy[i])?;
+            out.push(self.inner.update(trade).unwrap_or(f64::NAN));
+        }
+        Ok(out)
+    }
+    #[napi]
+    pub fn reset(&mut self) {
+        self.inner.reset();
+    }
+    #[napi(js_name = "isReady")]
+    pub fn is_ready(&self) -> bool {
+        self.inner.is_ready()
+    }
+    #[napi(js_name = "warmupPeriod")]
+    pub fn warmup_period(&self) -> u32 {
+        self.inner.warmup_period() as u32
+    }
+}
+
 // ============================== Microstructure: Price Impact ==============================
 //
 // Price-impact indicators consume a trade paired with the mid prevailing at