{
  "config": {
    "variant": "B + S + L; N absent",
    "simulator": "https://github.com/benedictbrady/amm-challenge/tree/6b6921f8d463314aa7c96234e1be25a25245f704",
    "b_source": "https://api.imdnotdead.fun/artifacts/5839483d4df69854030fd68b224659b379af881cd229df40a8bab825c2fa7db1",
    "seed_start": 2950000,
    "seed_end": 2953999,
    "n": 4000,
    "tuning": "none",
    "batch_size": 20,
    "workers": 8,
    "pairing": "Separate run_batch(X, vanilla, configs, 8) for X in {Strategy, NP2, B}; paired submission edges by seed. No candidate vs NP2 match. Sample sd (ddof=1) / sqrt(n).",
    "draws": "default_rng(seed): uniform(19,21) size, uniform(0.6,1) rate, uniform(0.000882,0.001008) sigma, in that order; canonical build_config; price seed=seed, retail seed=seed+1.",
    "steps": 10000,
    "compiler": {
      "version": "0.8.24",
      "optimizer_runs": 200,
      "viaIR": true,
      "evm": "paris"
    },
    "L": {
      "slow_later_alpha": 30000000000000000,
      "fast_later_alpha": 60000000000000000,
      "same_direction_second_slow_alpha_unchanged": 120000000000000000
    },
    "S": {
      "spot_slot": 16,
      "g": "min(elapsed-1,4), only first print and elapsed>=2",
      "center": "(wmul(previousSpot,WAD-prevBidFee)+wdiv(previousSpot,WAD-prevAskFee))/2",
      "w": "WAD - _powWad(925000000000000000,g)",
      "slow_alpha_and_gate_multiplier": "WAD-wmul(300000000000000000,w)",
      "ordering": "Silence shift precedes slow innovation and alpha/gate update; fast estimator unchanged. Gate scaling follows MIN_GATE floor.",
      "initial_spot": "Before first trade slot 16 is zero, so use initialized pHat; thereafter slot 16 records each post-trade spot."
    },
    "np2_sha256": "51f1c1a9d4999ee460eb8bbc66880da8074b173399a4f5d71f96671482e18ac0"
  },
  "code": "// SPDX-License-Identifier: MIT\npragma solidity ^0.8.24;\n\nimport {AMMStrategyBase} from \"./AMMStrategyBase.sol\";\nimport {TradeInfo} from \"./IAMMStrategy.sol\";\n\ncontract Strategy is AMMStrategyBase {\n    uint256 constant ELAPSED_CAP = 8;\n    uint256 constant SIGNAL_THRESHOLD = WAD / 650;\n    uint256 constant DIR_DECAY = 750000000000000000;\n    uint256 constant ACT_DECAY = 530000000000000000;\n    uint256 constant SIZE_DECAY = 530000000000000000;\n    uint256 constant TOX_DECAY = 910000000000000000;\n    uint256 constant SIGMA_DECAY = 690000000000000000;\n    uint256 constant LAMBDA_DECAY = 990000000000000000;\n    uint256 constant SIZE_BLEND_DECAY = 828000000000000000;\n    uint256 constant TOX_BLEND_DECAY = 51000000000000000;\n    uint256 constant ACT_BLEND_DECAY = 985000000000000000;\n    uint256 constant PHAT_ALPHA = 270000000000000000;\n    uint256 constant PHAT_ALPHA_RETAIL = 60000000000000000;\n    uint256 constant PHAT_ALPHA_SAME = 120000000000000000;\n    uint256 constant REVERT_U = 0;\n    uint256 constant DIR_IMPACT_MULT = 4;\n    uint256 constant GATE_SIGMA_MULT = 7200000000000000000;\n    uint256 constant MIN_GATE = 30000000000000000;\n    uint256 constant TRADE_TOX_BOOST = 3500 * BPS;\n    uint256 constant STALE_ATTRACT_FRAC = 1050000000000000000;\n    uint256 constant RET_CAP = WAD / 35;\n    uint256 constant TOX_CAP = WAD / 5;\n    uint256 constant TRADE_RATIO_CAP = WAD / 5;\n    uint256 constant LAMBDA_CAP = 1820000000000000000;\n    uint256 constant STEP_COUNT_CAP = 64;\n    uint256 constant BASE_FEE = 4 * BPS;\n    uint256 constant SIGMA_COEF = 200000000000000000;\n    uint256 constant LAMBDA_COEF = 12 * BPS;\n    uint256 constant FLOW_SIZE_COEF = 4842 * BPS;\n    uint256 constant TOX_COEF = 300 * BPS;\n    uint256 constant TOX_QUAD_COEF = 15000 * BPS;\n    uint256 constant ACT_COEF = 91843 * BPS;\n    uint256 constant DIR_COEF = 20 * BPS;\n    uint256 constant DIR_TOX_COEF = 100 * BPS;\n    uint256 constant STALE_DIR_COEF = 6850 * BPS;\n    uint256 constant SIGMA_TOX_COEF = 500 * BPS;\n    uint256 constant TAIL_KNEE = 600 * BPS;\n    uint256 constant TAIL_SLOPE_PROTECT = 930000000000000000;\n    uint256 constant TAIL_SLOPE_ATTRACT = 850000000000000000;\n\n    function afterInitialize(uint256 initialX, uint256 initialY) external override returns (uint256, uint256) {\n        slots[0] = BASE_FEE; slots[1] = BASE_FEE; slots[2] = 0; slots[3] = WAD; slots[4] = 0;\n        slots[5] = initialX > 0 ? wdiv(initialY, initialX) : 100 * WAD;\n        slots[6] = 950000000000000; slots[7] = 800000000000000000; slots[8] = 2000000000000000;\n        slots[13] = 902500000000; slots[14] = slots[5]; slots[15] = 0; slots[9] = 0; slots[10] = 0; slots[11] = 0; slots[12] = 0;\n        return (BASE_FEE, BASE_FEE);\n    }\n\n    function afterSwap(TradeInfo calldata trade) external override returns (uint256, uint256) {\n        uint256 prevBidFee = slots[0]; uint256 prevAskFee = slots[1]; uint256 lastTs = slots[2];\n        uint256 dirState = slots[3]; uint256 actEma = slots[4]; uint256 pHat = slots[5];\n        uint256 sigmaHat = slots[6]; uint256 lambdaHat = slots[7]; uint256 sizeHat = slots[8];\n        uint256 toxEma = slots[9]; uint256 stepTradeCount = slots[10];\n\n        uint256 sigmaForFast = sigmaHat;\n        uint256 fastHat = slots[14];\n        uint256 uncertainty = slots[13];\n        uint256 silent = trade.timestamp > lastTs ? trade.timestamp - lastTs : 0;\n        bool isNewStep = trade.timestamp > lastTs;\n        if (isNewStep) {\n            uint256 elapsedRaw = trade.timestamp - lastTs;\n            uint256 elapsed = elapsedRaw > ELAPSED_CAP ? ELAPSED_CAP : elapsedRaw;\n            dirState = _decayCentered(dirState, DIR_DECAY, elapsed);\n            actEma = wmul(actEma, _powWad(ACT_DECAY, elapsed));\n            sizeHat = wmul(sizeHat, _powWad(SIZE_DECAY, elapsed));\n            toxEma = wmul(toxEma, _powWad(TOX_DECAY, elapsed));\n            if (stepTradeCount > 0 && elapsedRaw > 0) {\n                uint256 lambdaInst = (stepTradeCount * WAD) / elapsedRaw;\n                if (lambdaInst > LAMBDA_CAP) lambdaInst = LAMBDA_CAP;\n                lambdaHat = wmul(lambdaHat, LAMBDA_DECAY) + wmul(lambdaInst, WAD - LAMBDA_DECAY);\n            }\n            uncertainty += wmul(sigmaForFast, sigmaForFast) * elapsedRaw;\n            if (uncertainty > 100000000000000) uncertainty = 100000000000000;\n            stepTradeCount = 0;\n        }\n\n        bool firstInStep = stepTradeCount == 0;\n        uint256 spot = trade.reserveX > 0 ? wdiv(trade.reserveY, trade.reserveX) : pHat;\n        if (pHat == 0) pHat = spot;\n\n        uint256 feeUsed = trade.isBuy ? prevBidFee : prevAskFee;\n        uint256 gamma = feeUsed < WAD ? WAD - feeUsed : 0;\n        uint256 pImplied;\n        if (gamma == 0) { pImplied = spot; }\n        else { pImplied = trade.isBuy ? wmul(spot, gamma) : wdiv(spot, gamma); }\n\n        // Silence observation from our last post-trade spot and outstanding fees.\n        uint256 silenceScale = WAD;\n        if (firstInStep && silent > 1) {\n            uint256 g = silent - 1;\n            if (g > 4) g = 4;\n            uint256 w = WAD - _powWad(925000000000000000, g);\n            uint256 previousSpot = slots[16] > 0 ? slots[16] : pHat;\n            uint256 center = (wmul(previousSpot, WAD - prevBidFee)\n                + wdiv(previousSpot, WAD - prevAskFee)) / 2;\n            if (center >= pHat) pHat += wmul(w, center - pHat);\n            else pHat -= wmul(w, pHat - center);\n            silenceScale = WAD - wmul(300000000000000000, w);\n        }\n\n        {\n            uint256 ret = pHat > 0 ? wdiv(absDiff(pImplied, pHat), pHat) : 0;\n            uint256 alpha = firstInStep ? PHAT_ALPHA : 30000000000000000;\n            uint256 prePhat = pHat;\n            bool secondPrint = !firstInStep && stepTradeCount == 1;\n            bool sameDir = false; bool oppDir = false;\n            if (secondPrint) {\n                bool up2 = pImplied >= pHat;\n                uint256 d1 = slots[12];\n                if (d1 != 0) { sameDir = (d1 == 1) == up2; oppDir = !sameDir; }\n                if (sameDir) alpha = PHAT_ALPHA_SAME;\n            }\n            if (firstInStep) { slots[11] = pHat; slots[12] = pImplied >= pHat ? 1 : 2; }\n            uint256 adaptiveGate = wmul(sigmaHat, GATE_SIGMA_MULT);\n            if (adaptiveGate < MIN_GATE) adaptiveGate = MIN_GATE;\n            alpha = wmul(alpha, silenceScale);\n            adaptiveGate = wmul(adaptiveGate, silenceScale);\n            if (ret <= adaptiveGate) { pHat = wmul(pHat, WAD - alpha) + wmul(pImplied, alpha); }\n            if (oppDir && REVERT_U > 0) {\n                uint256 pre = slots[11];\n                if (pre > pHat) pHat = pHat + wmul(pre - pHat, REVERT_U);\n                else pHat = pHat - wmul(pHat - pre, REVERT_U);\n            }\n            if (firstInStep) {\n                if (ret > RET_CAP) ret = RET_CAP;\n                sigmaHat = wmul(sigmaHat, SIGMA_DECAY) + wmul(ret, WAD - SIGMA_DECAY);\n            }\n        }\n\n        // Interior retail routing equalizes fee-adjusted marginal prices.\n        // Subsequent trades in a step cannot be the initial arbitrage trade.\n        if (!firstInStep && feeUsed > 30 * BPS && gamma > 0) {\n            uint256 normalSpot = trade.isBuy\n                ? wdiv(wmul(spot, gamma), WAD - 30 * BPS)\n                : wdiv(wmul(spot, WAD - 30 * BPS), gamma);\n            pHat = wmul(pHat, 90 * WAD / 100) + wmul(normalSpot, 10 * WAD / 100);\n        }\n\n        {\n            uint256 ret = fastHat > 0 ? wdiv(absDiff(pImplied, fastHat), fastHat) : 0;\n            uint256 alpha;\n            if (firstInStep) {\n                uint256 processSigma = sigmaForFast;\n                uint256 obsVar = uncertainty + wmul(processSigma, processSigma);\n                uint256 probArb;\n                uint256 z2 = wdiv(wmul(ret, ret), obsVar);\n                uint256 density = _powWad(wdiv(WAD, WAD + z2 / 16), 8);\n                uint256 sigmaObs = sqrt(obsVar * WAD);\n                uint256 odds = wmul(density, wdiv(6700000000000000, sigmaObs));\n                bool arbFlag = ret <= wmul(sigmaForFast, 1220000000000000000);\n                uint256 prior = arbFlag ? 650000000000000000 : 400000000000000000;\n                uint256 tr = trade.reserveY > 0 ? wdiv(trade.amountY, trade.reserveY) : 0;\n                if (tr > 3000000000000000) prior = wmul(prior, 6 * WAD / 10);\n                if (silent > 1) prior = wmul(prior, 8 * WAD / 10);\n                odds = wmul(odds, wdiv(prior, WAD - prior));\n                probArb = wdiv(odds, WAD + odds);\n                alpha = wmul(probArb, 600000000000000000) + wmul(WAD - probArb, 80000000000000000);\n                slots[15] = pImplied >= fastHat ? 1 : 2;\n                uncertainty = wmul(uncertainty, WAD - alpha);\n            } else {\n                if ((slots[15] == 1) == (pImplied >= fastHat)) alpha = PHAT_ALPHA_RETAIL;\n            }\n            uint256 gate = wmul(sigmaHat, GATE_SIGMA_MULT);\n            if (gate < MIN_GATE) gate = MIN_GATE;\n            if (ret <= gate) fastHat = wmul(fastHat, WAD - alpha) + wmul(pImplied, alpha);\n            slots[13] = uncertainty;\n        }\n\n        if (!firstInStep && feeUsed > 30 * BPS && gamma > 0) {\n            uint256 normalObs = trade.isBuy\n                ? wdiv(wmul(spot, gamma), WAD - 30 * BPS)\n                : wdiv(wmul(spot, WAD - 30 * BPS), gamma);\n            if ((slots[15] == 1) == (normalObs >= fastHat)) {\n                fastHat = wmul(fastHat, 9 * WAD / 10) + wmul(normalObs, WAD / 10);\n            }\n        }\n        slots[14] = fastHat;\n        uint256 tradeRatio = trade.reserveY > 0 ? wdiv(trade.amountY, trade.reserveY) : 0;\n        if (tradeRatio > TRADE_RATIO_CAP) tradeRatio = TRADE_RATIO_CAP;\n\n        if (tradeRatio > SIGNAL_THRESHOLD) {\n            uint256 push = tradeRatio * DIR_IMPACT_MULT;\n            if (push > WAD / 4) push = WAD / 4;\n            if (trade.isBuy) {\n                dirState = dirState + push;\n                if (dirState > 2 * WAD) dirState = 2 * WAD;\n            } else {\n                dirState = dirState > push ? dirState - push : 0;\n            }\n            actEma = wmul(actEma, ACT_BLEND_DECAY) + wmul(tradeRatio, WAD - ACT_BLEND_DECAY);\n            sizeHat = wmul(sizeHat, SIZE_BLEND_DECAY) + wmul(tradeRatio, WAD - SIZE_BLEND_DECAY);\n            if (sizeHat > WAD) sizeHat = WAD;\n        }\n\n        uint256 tox = pHat > 0 ? wdiv(absDiff(spot, pHat), pHat) : 0;\n        if (tox > TOX_CAP) tox = TOX_CAP;\n        toxEma = wmul(toxEma, TOX_BLEND_DECAY) + wmul(tox, WAD - TOX_BLEND_DECAY);\n        uint256 toxSignal = toxEma;\n\n        stepTradeCount = stepTradeCount + 1;\n        if (stepTradeCount > STEP_COUNT_CAP) stepTradeCount = STEP_COUNT_CAP;\n\n        uint256 flowSize = wmul(lambdaHat, sizeHat);\n        uint256 fBase = BASE_FEE + wmul(SIGMA_COEF, sigmaHat) + wmul(LAMBDA_COEF, lambdaHat) + wmul(FLOW_SIZE_COEF, flowSize);\n        uint256 fMid = fBase + wmul(TOX_COEF, toxSignal) + wmul(TOX_QUAD_COEF, wmul(toxSignal, toxSignal)) + wmul(ACT_COEF, actEma);\n        fMid = fMid + wmul(SIGMA_TOX_COEF, wmul(sigmaHat, toxSignal));\n\n        uint256 dirDev; bool sellPressure;\n        if (dirState >= WAD) { dirDev = dirState - WAD; sellPressure = true; }\n        else { dirDev = WAD - dirState; sellPressure = false; }\n\n        uint256 skew = wmul(DIR_COEF, dirDev) + wmul(DIR_TOX_COEF, wmul(dirDev, toxSignal));\n        uint256 bidFee; uint256 askFee;\n        if (sellPressure) {\n            bidFee = fMid + skew;\n            askFee = fMid > skew ? fMid - skew : 0;\n        } else {\n            askFee = fMid + skew;\n            bidFee = fMid > skew ? fMid - skew : 0;\n        }\n\n        {\n            uint256 staleHat = wmul(pHat, 700000000000000000) + wmul(fastHat, 300000000000000000);\n            uint256 staleTox = wdiv(absDiff(spot, staleHat), staleHat);\n            if (staleTox > TOX_CAP) staleTox = TOX_CAP;\n            uint256 staleShift = wmul(STALE_DIR_COEF, staleTox);\n            uint256 attractShift = wmul(staleShift, STALE_ATTRACT_FRAC);\n            if (spot >= staleHat) {\n                bidFee = bidFee + staleShift;\n                askFee = askFee > attractShift ? askFee - attractShift : 0;\n            } else {\n                askFee = askFee + staleShift;\n                bidFee = bidFee > attractShift ? bidFee - attractShift : 0;\n            }\n        }\n\n        {\n            bool tradeAligned = (trade.isBuy && spot >= pHat) || (!trade.isBuy && spot < pHat);\n            if (tradeAligned) {\n                uint256 tradeBoost = wmul(TRADE_TOX_BOOST, tradeRatio);\n                if (trade.isBuy) { bidFee = bidFee + tradeBoost; }\n                else { askFee = askFee + tradeBoost; }\n            }\n        }\n\n        if (sellPressure) {\n            bidFee = clampFee(_compressTailWithSlope(bidFee, TAIL_SLOPE_PROTECT));\n            askFee = clampFee(_compressTailWithSlope(askFee, TAIL_SLOPE_ATTRACT));\n        } else {\n            askFee = clampFee(_compressTailWithSlope(askFee, TAIL_SLOPE_PROTECT));\n            bidFee = clampFee(_compressTailWithSlope(bidFee, TAIL_SLOPE_ATTRACT));\n        }\n\n        slots[16] = spot;\n        slots[0] = bidFee; slots[1] = askFee; slots[2] = trade.timestamp;\n        slots[3] = dirState; slots[4] = actEma; slots[5] = pHat;\n        slots[6] = sigmaHat; slots[7] = lambdaHat; slots[8] = sizeHat;\n        slots[9] = toxEma; slots[10] = stepTradeCount;\n\n        return (bidFee, askFee);\n    }\n\n    function _compressTailWithSlope(uint256 fee, uint256 slope) internal pure returns (uint256) {\n        if (fee <= TAIL_KNEE) return fee;\n        return TAIL_KNEE + wmul(fee - TAIL_KNEE, slope);\n    }\n\n    function _powWad(uint256 factor, uint256 exp) internal pure returns (uint256 result) {\n        result = WAD;\n        while (exp > 0) {\n            if (exp & 1 == 1) result = wmul(result, factor);\n            factor = wmul(factor, factor);\n            exp >>= 1;\n        }\n    }\n\n    function _decayCentered(uint256 centered, uint256 decayFactor, uint256 elapsed) internal pure returns (uint256) {\n        uint256 mul = _powWad(decayFactor, elapsed);\n        if (centered >= WAD) { return WAD + wmul(centered - WAD, mul); }\n        uint256 below = wmul(WAD - centered, mul);\n        return below < WAD ? WAD - below : 0;\n    }\n\n    function getName() external pure override returns (string memory) { return \"no_cubic\"; }\n}\n",
  "sha256": "9e2f512a93955eff9c32d8434bb94d5238e312995e257d1fca8c90f31cdc5788",
  "b_sha256": "218426004abed3b6cb69f4ef133fea8e4789ddbeae37bd11e94e5ffc5f2a77cb",
  "paired_np2": {
    "n": 4000,
    "mean_diff": 0.6425757174162329,
    "se": 0.014047689703924834,
    "worst": [
      {
        "seed": 2953238,
        "candidate_edge": 590.5358138491817,
        "np2_edge": 601.0508144806328,
        "diff": -10.515000631451016
      },
      {
        "seed": 2951947,
        "candidate_edge": 682.439232169997,
        "np2_edge": 685.3305402326987,
        "diff": -2.8913080627016825
      },
      {
        "seed": 2953787,
        "candidate_edge": 580.5650174217224,
        "np2_edge": 583.2719729621431,
        "diff": -2.706955540420722
      },
      {
        "seed": 2952511,
        "candidate_edge": 670.1278079347153,
        "np2_edge": 672.5442195842797,
        "diff": -2.416411649564452
      },
      {
        "seed": 2953666,
        "candidate_edge": 500.7527191913698,
        "np2_edge": 503.1247131216689,
        "diff": -2.371993930299084
      }
    ]
  },
  "paired_b": {
    "n": 4000,
    "mean_diff": 0.15238053770375534,
    "se": 0.01134354181198657
  },
  "seconds_per_sim": 0.06433378604069973,
  "blocked": null,
  "notes": {
    "S_provenance": "Reimplemented solely from the requester-provided silence-a definition, read directly in the task. No separate silence-a artifact was supplied or consulted. No N artifact or mix constants/helpers were used.",
    "hash_definition": "SHA-256 of full UTF-8 Strategy.sol contents in code, including its trailing LF.",
    "baseline_reconstruction": "TWO code plus NP block from // Interior retail routing up to uint256 tradeRatio =, exclusive; matches full required NP2 hash. Source URLs and exact passages are in sources.json.",
    "calibration": {
      "CH": 525.5258821780834,
      "NP2": 526.1155722459862
    },
    "calibration_seeds": "0..999; CH and NP2 separately vs vanilla, 20 seeds/call.",
    "validation": "amm-match validate scratch/Strategy.sol passed. Supplied item-specific setup script completed once, including StarterStrategy validation.",
    "mechanism_checks": "16 direct EVM state checks passed: elapsed 1,2,3,5,10 with stored spot, initial fallback, and out-of-gate innovations; separate later-print check confirms slow 0.03 versus fast 0.06.",
    "initialization_repair": "An initial candidate initialized an additional slot and exceeded the 250000 initialization gas cap. Removed that extra initialization write and used existing initialized pHat until first print. The repaired frozen candidate passed validation before confirmation.",
    "fresh_confirmation": "Each of the three strategies was evaluated exactly once per seed in this block; no tuning or selection on confirmation scores.",
    "timing_definition": "Wall time inside run_batch, including config construction, divided by number of individual market simulations; each market simulation pairs X with vanilla. Compilation/calibration excluded.",
    "seconds_per_sim_by_strategy": {
      "Strategy": 0.07460948563320562,
      "NP2": 0.04694503342278768,
      "B": 0.0714468390661059
    },
    "total_confirmation_seconds": 772.0054324883968,
    "fallback_2000_used": false,
    "fallback_rule": "First 20 seeds for each X were retained in confirmation; their aggregate wall seconds / 60 selected 2000 if >0.2, else 4000.",
    "mean_edges": {
      "Strategy": 526.4501611814397,
      "NP2": 525.8075854640235,
      "B": 526.297780643736
    },
    "interpretation": "Local simulation estimates; no live leaderboard result or placement claimed.",
    "dependencies": "Delivered Solidity uses only AMMStrategyBase.sol and IAMMStrategy.sol from the pinned simulator. No new runtime dependencies."
  }
}
