{ "item": "p1", "batch": "e05-position-rerun", "summary": "Design (a) position-in-step blend f=w*fR+(1-w)*fA is strongly NEGATIVE vs V2 at every tested setting (about -58 to -62 at s=1, about -37 to -40 at s=0.75; less blending is monotonically better, i.e. s->0 recovers V2). Do not submit. Frozen candidate fR=36 bps, s=0.75: holdout -39.82 +- 0.80 (n=256).", "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[3] = WAD;\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];\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 // S: infer a no-trade interval center from the last post-trade spot.\n uint256 silenceScale = WAD;\n if (firstInStep && silent > 1) {\n uint256 g = silent - 1;\n if (g > 1) g = 1;\n uint256 w = WAD - _powWad(800000000000000000, g);\n uint256 s = slots[16];\n if (s == 0) s = pHat;\n uint256 c = (wmul(s, WAD - prevBidFee) + wdiv(s, WAD - prevAskFee)) / 2;\n if (c >= pHat) pHat += wmul(w, c - pHat);\n else pHat -= wmul(w, pHat - c);\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 : PHAT_ALPHA_RETAIL;\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 {\n // Position-in-step quote: blend fR toward V2's fee fA by w.\n uint256 w = wmul(_sameStepProb(lambdaHat, stepTradeCount), 750000000000000000);\n uint256 fR = 36 * BPS;\n bidFee = wmul(w, fR) + wmul(WAD - w, bidFee);\n askFee = wmul(w, fR) + wmul(WAD - w, askFee);\n }\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[16] = spot;\n slots[9] = toxEma; slots[10] = stepTradeCount;\n\n return (bidFee, askFee);\n }\n\n\n // w = P(another same-step retail print | k prints seen this step), N ~ Poisson(L).\n // k == 1: 1 - exp(-L); k >= 2: P(N > k) / P(N >= k).\n function _sameStepProb(uint256 L, uint256 k) internal pure returns (uint256) {\n uint256 x = L / 8;\n uint256 e = WAD + x + x * x / (2 * WAD) + x * x / WAD * x / (6 * WAD);\n e = e * e / WAD; e = e * e / WAD; e = e * e / WAD;\n uint256 p = WAD * WAD / e;\n if (k <= 1) return WAD - p;\n if (k > 4) k = 4;\n uint256 cdf = 0;\n for (uint256 j = 0; j < k; j++) { cdf += p; p = p * L / ((j + 1) * WAD); }\n if (cdf >= WAD) return 0;\n uint256 tail = WAD - cdf;\n if (p >= tail) return 0;\n return (tail - p) * WAD / tail;\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": "67ef3f00e4ecc81fe1a20f6f5892bad05ca56f7c4587c563a972da6421474a73", "design": "V2 estimators and fee pipeline unchanged; fA = V2's final clamped bidFee/askFee. After the k-th print in a step (k = V2's stepTradeCount after increment, capped at 4 in the tail loop), w = s*(1-exp(-L)) for k=1 and s*P(N>k)/P(N>=k) for k>=2, N~Poisson(L), L = V2's lambdaHat; exp(-L) via (1+x+x^2/2+x^3/6)^8 with x=L/8. Return and store per side f = w*fR + (1-w)*fA (stored fees feed V2's feeUsed). afterInitialize zero writes removed (slots 2,4,9,10,11,12,15).", "tuning": [ { "variant": "fR=26,s=1", "seeds": "10000..10063", "n": 64, "mean_diff": -62.4443, "se": 2.0063 }, { "variant": "fR=28,s=1", "seeds": "10000..10063", "n": 64, "mean_diff": -60.6422, "se": 1.9788 }, { "variant": "fR=30,s=1", "seeds": "10000..10063", "n": 64, "mean_diff": -59.6076, "se": 1.9618 }, { "variant": "fR=32,s=1", "seeds": "10000..10063", "n": 64, "mean_diff": -59.054, "se": 1.9503 }, { "variant": "fR=34,s=1", "seeds": "10000..10063", "n": 64, "mean_diff": -58.6363, "se": 1.9108 }, { "variant": "fR=36,s=1", "seeds": "10000..10063", "n": 64, "mean_diff": -58.4503, "se": 1.8802 }, { "variant": "fR=35,s=1", "seeds": "10000..10063", "n": 64, "mean_diff": -58.5459, "se": 1.8953 }, { "variant": "fR=37,s=1", "seeds": "10000..10063", "n": 64, "mean_diff": -58.5138, "se": 1.8741 }, { "variant": "fR=36,s=0.75", "seeds": "10000..10063", "n": 64, "mean_diff": -37.3712, "se": 1.2699 }, { "variant": "fR=37,s=0.75", "seeds": "10000..10063", "n": 64, "mean_diff": -37.4728, "se": 1.2661 }, { "variant": "fR=36,s=0.75", "seeds": "12000..12127", "n": 128, "mean_diff": -39.6664, "se": 1.0404 }, { "variant": "fR=37,s=0.75", "seeds": "12000..12127", "n": 128, "mean_diff": -39.7648, "se": 1.0336 } ], "paired": { "n": 256, "mean_diff": -39.8193, "se": 0.8006, "worst": [ { "seed": 4200217, "diff": -95.3957 }, { "seed": 4200117, "diff": -94.7016 }, { "seed": 4200075, "diff": -78.1019 }, { "seed": 4200235, "diff": -77.0497 }, { "seed": 4200054, "diff": -76.0174 } ] }, "gas": { "max_ok": 244346, "oog": 2, "reverts": 0, "other_halts": 0, "init_max": 220932 }, "v2_gas": { "max_ok": 242800, "oog": 2, "other_halts": 0, "init_max": 236377, "seeds": "4200000..4200255" }, "oog_note": "Candidate OOG equals V2 OOG on every seed block measured (screen 10000..10063: 4 vs 4; select 12000..12127: 1 vs 1; holdout: 2 vs 2), so valid under the brief's OOG rule. V2's OOG rate here (~4 per 64 seeds on the screen block) is higher than the brief's '1 per 300k calls'.", "seeds": { "screen": "10000..10063 (64, reduced from 256)", "select": "12000..12127 (128, reduced from 512)", "holdout": "4200000..4200255 (256, reduced from 2000)" }, "deviations": "Seed counts reduced: about 1.2 s per seed per strategy on this 8-core machine, and run_batch was OOM-killed at >=128 seeds per call, so runs were split into 64-seed chunks. 10 screen variants (brief allowed up to 12). The harness was repaired to build configs only for the requested seeds (checked identical to MatchRunner._build_configs on seeds 10..19) and to treat only non-OOG errors as invalid. The candidate peaks at 244,346 gas, about 1.5k above V2 on the same seeds; it was not reduced further because a normalSpot dedupe hit stack-too-deep.", "valid": true, "blocked": null }