diff --git a/docs/evidence/typed-adjustment-factor-snapshot-20260907.json b/docs/evidence/typed-adjustment-factor-snapshot-20260907.json
new file mode 100644
index 0000000..a9ffc8a
--- /dev/null
+++ b/docs/evidence/typed-adjustment-factor-snapshot-20260907.json
@@ -0,0 +1,150 @@
+{
+  "schemaVersion": "fidc-typed-adjustment-factor-snapshot/v1",
+  "generatedAt": "2026-09-07T18:12:00+08:00",
+  "scope": "FIDC engine, backtest runner and strategy runtime",
+  "changes": {
+    "engineCommit": "04b45adf98772f4ce3cd8b7a2c08d76480655fee",
+    "backtestServiceCommit": "76748bbc3d2cfc4d76ff8e35c5fcda1fcddd00ec",
+    "tradingPlatformCommit": "bec62d0f7f6126a36ec0a101f7b1a66b138537eb",
+    "datasetSchemaVersion": 58,
+    "sourceRowCacheSchemaVersion": 28,
+    "contract": "adjustment_factor_backward1 remains a nullable typed field from Arrow decode through DailyFactorSnapshot and AdjustedCloseSeries; dynamic NumericFactorMap values stay sparse",
+    "legacyInputPolicy": "extra_factors containing adjustment_factor_backward1 and non-positive or non-finite typed adjustment values are rejected"
+  },
+  "tests": {
+    "fidcCore": "445 passed, 6 ignored",
+    "backtestRunner": "351 passed, 3 ignored",
+    "backtestApi": "80 passed",
+    "strategyRuntime": "66 passed",
+    "runtimeRollingOrderRegression": "full 5/10/30/100-day framework rolling history produced a valid paper order"
+  },
+  "productionImplementation": {
+    "engineCommit": "04b45adf98772f4ce3cd8b7a2c08d76480655fee",
+    "serviceCommit": "76748bbc3d2cfc4d76ff8e35c5fcda1fcddd00ec",
+    "identitySha256": "2c0ab93663018f4fae8d61ba0c522c0f796837d952bbfb26a6bc229cc52bd722",
+    "runnerBinarySha256": "8591dfa763a52e06467dfe2ff2c8bef4d382ef875b356009fe5a7e8ea2013ea3",
+    "serviceBinarySha256": "4e467981f569e265c4ccc862c04be85eb99e9f4d107878785c5961a8b382d65f",
+    "status": "verified"
+  },
+  "fiveYearFreshProcess": {
+    "baseline": {
+      "runId": "btr_1788772852314_617886_0",
+      "dataSeconds": 14.121,
+      "sourceQuerySeconds": 4.304,
+      "datasetConstructSeconds": 3.672,
+      "riskFreeRateSeconds": 2.77,
+      "totalSeconds": 20.947,
+      "queryCompletedRssKb": 6654344,
+      "datasetConstructCompletedRssKb": 12775136
+    },
+    "candidate": {
+      "runId": "btr_1788775107699_632665_0",
+      "dataSeconds": 13.198,
+      "sourceQuerySeconds": 4.169,
+      "datasetConstructSeconds": 3.499,
+      "riskFreeRateSeconds": 0.01,
+      "totalSeconds": 17.381,
+      "queryCompletedRssKb": 6738520,
+      "datasetConstructCompletedRssKb": 12694000
+    },
+    "improvementPercent": {
+      "dataSeconds": 6.5364,
+      "sourceQuerySeconds": 3.1366,
+      "datasetConstructSeconds": 4.7113,
+      "datasetConstructCompletedRssKb": 0.6351,
+      "totalSecondsAfterRiskFreeNormalization": 4.4317
+    },
+    "comparisonNote": "total wall time is normalized only for the independently measured risk-free lookup difference; data and RSS values are compared directly"
+  },
+  "fiveYearMemoryCold": {
+    "baselineRunIds": [
+      "btr_1788772635840_613911_1",
+      "btr_1788772672944_613911_2",
+      "btr_1788772707181_613911_3"
+    ],
+    "candidateRunIds": [
+      "btr_1788775166889_632665_1",
+      "btr_1788775202156_632665_2",
+      "btr_1788775353507_632665_5"
+    ],
+    "baselineMedian": {
+      "totalSeconds": 16.809,
+      "dataSeconds": 12.8,
+      "sourceQuerySeconds": 4.411,
+      "dailyLoopSeconds": 1.077,
+      "datasetConstructSeconds": 3.701,
+      "engineSeconds": 3.278
+    },
+    "candidateMedian": {
+      "totalSeconds": 16.653,
+      "dataSeconds": 12.569,
+      "sourceQuerySeconds": 4.054,
+      "dailyLoopSeconds": 1.047,
+      "datasetConstructSeconds": 3.577,
+      "engineSeconds": 3.372
+    },
+    "improvementPercent": {
+      "totalSeconds": 0.9281,
+      "dataSeconds": 1.8047,
+      "sourceQuerySeconds": 8.0934,
+      "dailyLoopSeconds": 2.7855,
+      "datasetConstructSeconds": 3.3504,
+      "engineSeconds": -2.8676
+    },
+    "excludedQueueOutlier": {
+      "runId": "btr_1788775236942_632665_4",
+      "totalSeconds": 69.401,
+      "queueWaitSeconds": 48.625,
+      "blockingRunId": "btr_1788775223727_632665_3",
+      "reason": "another user backtest naturally occupied the single runner; it was not stopped or modified"
+    }
+  },
+  "controls": {
+    "currentClose": {
+      "runIds": [
+        "btr_1788775434926_632665_6",
+        "btr_1788775464828_632665_7",
+        "btr_1788775491657_632665_8"
+      ],
+      "medianTotalSeconds": 10.044,
+      "totalReturn": 0.3201517861398,
+      "tradeCount": 5351,
+      "canonicalSha256": "7204c6f41b8e39fbf1af7fc55cd601b80f3427a7aa058394ccd8b0b14ca48eed",
+      "resultStoreSha256": "0b4d24ed5ec2b27cc4135707b4c51c78eb2c3e35a20da8108610778c30c72c73"
+    },
+    "staticDaily": {
+      "runId": "btr_1788775531308_632665_9",
+      "totalReturn": 0.13228843240310018,
+      "tradeCount": 4445,
+      "canonicalSha256": "fdfa855295c0b55bdbe6f39952ead1515e844bf033ced974d3c3ddc037a5d0b1",
+      "resultStoreSha256": "697566645116c76ff837cd36f7f9bbd7ad3eb30510a5b95012fb730d5072d511"
+    },
+    "fullMinute": {
+      "runId": "btr_1788775545217_632665_10",
+      "totalReturn": 0.03473222656500008,
+      "tradeCount": 156,
+      "canonicalSha256": "7dae3a618932b90d36e9968c027f08a94d69b8fc6a56b1ea0cc1a2cb771d85b8",
+      "resultStoreSha256": "bbbd7080b8fd7f6e8c3a8132499842bd0e4d644dbfdc3e8dbca7d2c0c1381e93"
+    },
+    "nextOpenFiveYear": {
+      "totalReturn": 0.9922618879291,
+      "tradeCount": 25827,
+      "canonicalSha256": "ac1d167cb1e1073e1d1ecb01e914f94d7560081c1d238e6b4418d86233250719",
+      "resultStoreSha256": "79570e0ae6b07badc1b693dc897dd1381647d259a4fe44ed3e50bc215e2fd088"
+    },
+    "terminalAuditsClean": true
+  },
+  "tradingRuntimeDeployment": {
+    "sourceCommit": "bec62d0f7f6126a36ec0a101f7b1a66b138537eb",
+    "strategyRuntimeBinarySha256": "b28aa9a20bff232d5d24ba6c8072c02ff921dea69a5ca3cb81712323e2d88d24",
+    "healthPorts": [9100, 9101, 9102, 9103, 9104, 9130],
+    "allHealthChecksPassed": true,
+    "orderRoutingConfigurationChanged": false,
+    "observedOrderRoutingMode": "disabled"
+  },
+  "decision": {
+    "status": "accepted",
+    "reason": "all business hashes and runtime rolling semantics remain exact while five-year DataSet construction, data time and steady memory-cold wall time improve",
+    "nextTarget": "construct the immutable Base Panel directly from Arrow column buffers so the remaining SourceRowRecord and DailyFactorSnapshot row materialization can be removed"
+  }
+}