feat: add portfolio risk computation contracts

MODULE_SPEC.yaml

@@ -1,7 +1,7 @@
 {
   "schema_version": 1,
   "module_id": "quant_engine",
-  "authority": {"scope": "module_metadata", "subject": "quant_engine", "owner": "quant-engine-owner", "source": "MODULE_SPEC.yaml", "revision": 2, "effective_from": "2026-09-01T00:00:00+08:00"},
+  "authority": {"scope": "module_metadata", "subject": "quant_engine", "owner": "quant-engine-owner", "source": "MODULE_SPEC.yaml", "revision": 4, "effective_from": "2026-09-01T00:00:00+08:00"},
   "repository": {"name": "quant_engine", "workspace_id": "researchhub", "type": "research_engine", "maturity": "operational"},
   "bounded_context": {
     "domain": "quantitative-research-engine",
@@ -11,6 +11,7 @@
       "Submitting live orders, routing trades, managing brokerage accounts, or claiming transaction execution",
       "Owning market-data source facts, research-result publication, or platform presentation state",
       "Loading provider credentials, brokerage credentials, or production secrets",
+      "Granting portfolio approval, maker-checker decisions, publication eligibility, paper execution, or live execution authority",
       "Changing financial model semantics through module metadata"
     ]
   },
@@ -18,6 +19,8 @@
     {"id": "factor-and-indicator-calculation", "summary": "Calculate reusable alpha factors and technical indicators from caller-supplied data.", "status": "operational"},
     {"id": "execution-simulation", "summary": "Simulate costs, slippage, market constraints, fills, NAV, and PnL without live order routing.", "status": "operational"},
     {"id": "portfolio-backtesting", "summary": "Run weight-based backtests and benchmark comparisons.", "status": "operational"},
+    {"id": "backtest-evidence-contracts", "summary": "Identify governed offline backtest inputs and close existing research artifact evidence without persistence or decision authority.", "status": "operational"},
+    {"id": "portfolio-risk-computation-contracts", "summary": "Verify deterministic portfolio-computation receipts and expose S3-bound portfolio decisions and risk assessments without adding algorithms or execution authority.", "status": "operational"},
     {"id": "risk-and-performance-analysis", "summary": "Calculate portfolio decomposition, risk contribution, and performance statistics.", "status": "operational"}
   ],
   "data": {"owns": [
@@ -27,7 +30,11 @@
   "contracts": {
     "provides": [
       {"contract_id": "researchhub.factor-definition", "version": "1.0.0", "authority": "quant_engine", "path": "src/quant_engine/factor_contracts.py"},
-      {"contract_id": "researchhub.factor-set-ref", "version": "1.0.0", "authority": "quant_engine", "path": "src/quant_engine/factor_contracts.py"}
+      {"contract_id": "researchhub.factor-set-ref", "version": "1.0.0", "authority": "quant_engine", "path": "src/quant_engine/factor_contracts.py"},
+      {"contract_id": "researchhub.backtest-run-ref", "version": "1.0.0", "authority": "quant_engine", "path": "src/quant_engine/governed_pipeline.py"},
+      {"contract_id": "researchhub.backtest-evidence-manifest", "version": "1.0.0", "authority": "quant_engine", "path": "src/quant_engine/artifact.py"},
+      {"contract_id": "researchhub.portfolio-decision", "version": "1.0.0", "authority": "quant_engine", "path": "src/quant_engine/portfolio_risk_contracts.py"},
+      {"contract_id": "researchhub.risk-assessment", "version": "1.0.0", "authority": "quant_engine", "path": "src/quant_engine/portfolio_risk_contracts.py"}
     ],
     "consumes": [
       {"contract_id": "researchhub.dataset-snapshot", "version": "1.0.0", "authority": "researchhub.data", "admission": "qualified_immutable_envelope"},

README.md

@@ -26,8 +26,9 @@
 - `backtest` — weight-based 多日仿真（rebalance_table / compute_nav / compare_to_benchmark）
 - `portfolio_construction` — 多期因子分数 → Top-K → 等权目标权重表
 - `research_pipeline` — 因子日 → 下一真实交易日 → 显式执行价 → 日末估值 → 成本后绩效（防前视编排）
-- `governed_pipeline` — 数据快照 → 因子版本 → 策略版本 → 回测运行 → 目标组合 → 风险决策 → Paper 订单意图；全链路带确定性 ID，风险拒绝时禁止生成订单意图
+- `governed_pipeline` — 数据快照 → 因子版本 → 策略版本 → 回测运行 → 目标组合 → 风险决策 → Paper 订单意图；同时拥有输入/配置/重放血缘决定的 `BacktestRunRef`
-- `artifact` — 版本化、确定性、存储中立的完整 research run 事实表与 manifest
+- `artifact` — 版本化、确定性、存储中立的完整 research run 事实表，以及只映射现有表的 `BacktestEvidenceManifest`
+- `portfolio_risk_contracts` — S3 证据闭合的 `PortfolioDecision` / `RiskAssessment` v1；独立复核 freshness、约束与 computation receipt，并复用既有标签安全风险分解
 - `attribution` — 基于实际成交后持仓的隔夜 / 日内 / 交易成本逐日收益归因与闭合审计
 - `metrics` — 绝对绩效 + 严格日期对齐的 TE / IR / alpha / beta 基准相对绩效
 - `factor_library` — 通用方法（turnover / winsorize / IC / OLS / jb_test）
@@ -241,6 +242,129 @@ identity 均保持不变。迁移只能通过 content-addressed `LegacyFactorBin
 `bind_legacy_factor()` 或 `project_legacy_factor()`；后者是有损投影，不表示旧 digest 与新定义
 digest 等价，也不会把旧 run 静默升级为新合同。
 
+## 回测引用与证据合同 v1
+
+`quant_engine.governed_pipeline.BacktestRunRef` 是合格回测运行身份的唯一权威。`run_id` 只由
+已验收的 Dataset Snapshot / Data Foundation / `FactorSetRef` 身份、universe、日历与公司行动
+祖先、策略、执行/成本模型、严格整数 seed、完整代码提交、环境锁、配置、时间和重放血缘决定；
+它不包含任何输出摘要。重放必须绑定直接父运行、连续 attempt 和不变的
+`replay_spec_digest`，输入漂移或血缘环会失败关闭。
+
+`quant_engine.artifact.BacktestEvidenceManifest` 只摘要 `ResearchRunArtifact` 已有的九张事实表。
+固定 `offline_research_v1` 映射为 `run`、`signal`、`fill`、`position_nav`、`performance`、
+`attribution`、`risk_snapshot` 与 `replay`；每张表都保留列模式摘要、行数和内容摘要，空 risk
+表也必须有稳定 schema。`manifest_id` 由完整 RunRef 与输出证据决定，因此结果变化不会反向改变
+`run_id`。当前 artifact 不拥有订单或拒绝事实，所以此画像明确不声明 `order` / `rejection`。
+
+旧 `BacktestRun` 只能通过 `build_legacy_backtest_evidence_manifest()` 显式映射为
+`LEGACY_EXPLORATORY`；不能隐式提升为 `CONTRACT_QUALIFIED`。所有资格均只描述离线证据闭合，
+不表示投资有效、组合获批、Paper、生产或实盘就绪。
+
+## 组合决策与风险评估合同 v1
+
+`quant_engine.portfolio_risk_contracts` 是现有计算 owner 外围的薄合同层。创建
+`PortfolioDecision` 必须同时提供完整 `BacktestRunRef`、嵌入同一 RunRef 的
+`CONTRACT_QUALIFIED` 非 legacy `BacktestEvidenceManifest`、现有 `PortfolioTarget`、
+`FreshnessPolicy`、`ConstraintSetV1` 与 `ComputationReceipt`。适配器会从权威输入独立重算
+receipt 的 input/constraint/output digest、敞口、持仓数和 L1 turnover 残差；receipt 自报
+成功、fallback 或放宽 tolerance 均不能替代复核。
+
+```python
+from quant_engine.portfolio_risk_contracts import (
+    ComputationReceipt,
+    ConstraintSetV1,
+    FreshnessPolicy,
+    assess_portfolio_risk,
+    build_portfolio_decision,
+    compute_portfolio_receipt_digests,
+)
+
+freshness = FreshnessPolicy(
+    max_manifest_age_seconds=3600,
+    max_covariance_age_days=5,
+)
+constraints = ConstraintSetV1(
+    gross_exposure_max=1.0,
+    single_asset_max=0.10,
+    position_count_max=20,
+    turnover_max=0.30,
+)
+
+# 生产者先形成公开 canonical digest；decision 构建时仍会独立重算。
+expected = compute_portfolio_receipt_digests(
+    backtest_run_ref=run_ref,
+    manifest=evidence_manifest,
+    target=portfolio_target,
+    objective_name="long_only_allocation",
+    objective_version="1.0.0",
+    objective_digest=objective_digest,
+    model_name="factor_weighting",
+    model_version="1.0.0",
+    model_digest=model_digest,
+    expected_return_digest=expected_return_digest,
+    covariance_digest=covariance_digest,
+    scenario_digest=scenario_digest,
+    constraints=constraints,
+    freshness_policy=freshness,
+    prior_weights=prior_weights,
+)
+
+receipt = ComputationReceipt(
+    algorithm="factor_weighting",
+    algorithm_version="1.0.0",
+    implementation_digest=implementation_digest,
+    parameter_digest=parameter_digest,
+    input_digest=expected["input_digest"],
+    constraint_digest=expected["constraint_digest"],
+    output_digest=expected["output_digest"],
+    status="completed",
+    solver_required=False,
+    solver_name=None,
+    solver_version=None,
+    solver_config_digest=None,
+    iterations=None,
+    objective_value=None,
+    max_constraint_residual=expected["max_constraint_residual"],
+    tolerance=1e-12,
+    computed_at=computed_at,
+)
+
+decision = build_portfolio_decision(
+    backtest_run_ref=run_ref,
+    manifest=evidence_manifest,
+    target=portfolio_target,
+    objective_name="long_only_allocation",
+    objective_version="1.0.0",
+    objective_digest=objective_digest,
+    model_name="factor_weighting",
+    model_version="1.0.0",
+    model_digest=model_digest,
+    expected_return_digest=expected_return_digest,
+    covariance_digest=covariance_digest,
+    scenario_digest=scenario_digest,
+    constraints=constraints,
+    freshness_policy=freshness,
+    receipt=receipt,
+    computed_at=computed_at,
+    prior_weights=prior_weights,
+)
+
+assessment = assess_portfolio_risk(
+    portfolio_decision=decision,
+    backtest_run_ref=run_ref,
+    manifest=evidence_manifest,
+    covariance=covariance_snapshot,
+    risk_model_name="euler_volatility",
+    risk_model_version="1.0.0",
+    risk_model_digest=risk_model_digest,
+)
+```
+
+`source_universe_digest` 保留 S3 研究 universe 身份，`portfolio_asset_set_digest` 只描述实际
+目标资产标签；二者不会互相冒充成员证明。风险评估在任何数值计算前要求 covariance、target、
+RunRef 的 dataset identity 三方一致，并且只调用一次现有 `labeled_component_risk()`。合同中的
+`qualified` 仅表示 S4.1 计算证据闭合，不授予 maker-checker、发布、订单、Paper、生产或实盘权限。
+
 ## 治理垂直切片
 
 `governed_pipeline` 不复制因子、回测、组合或执行算法，只编排现有能力并补充版本与风险契约。

src/quant_engine/governed_pipeline.py

@@ -11,27 +11,74 @@ import hashlib
 import json
 import math
 import re
-from collections.abc import Mapping
+from collections.abc import Mapping, Sequence
 from dataclasses import asdict, dataclass
 from datetime import UTC, datetime
 from enum import StrEnum
 from types import MappingProxyType
+from typing import Any, Never, Self
 
 import pandas as pd
 
 from quant_engine.execution import ExecutionConfig
 from quant_engine.factor_contracts import (
     ContractErrorCode,
+    DataFoundationEnvelope,
+    DatasetSnapshotEnvelope,
     FactorContractError,
     FactorDefinition,
+    FactorSetRef,
     LegacyFactorBinding,
+    canonical_json,
+    canonical_json_bytes,
 )
 from quant_engine.research_pipeline import FactorBacktestResult, run_factor_backtest_research
 
 _SHA256 = re.compile(r"^[0-9a-f]{64}$")
+_PREFIXED_SHA256 = re.compile(r"^sha256:[0-9a-f]{64}$")
 _GIT_SHA = re.compile(r"^[0-9a-f]{40}$")
+_LOGICAL_ID = re.compile(r"^[a-z0-9][a-z0-9._-]{0,127}$")
+_SEMVER = re.compile(
+    r"^(?:0|[1-9][0-9]*)\.(?:0|[1-9][0-9]*)\."
+    r"(?:0|[1-9][0-9]*)"
+    r"(?:-(?:0|[1-9][0-9]*|[0-9A-Za-z-]*[A-Za-z-][0-9A-Za-z-]*)"
+    r"(?:\.(?:0|[1-9][0-9]*|[0-9A-Za-z-]*[A-Za-z-][0-9A-Za-z-]*))*)?"
+    r"(?:\+[0-9A-Za-z-]+(?:\.[0-9A-Za-z-]+)*)?$"
+)
+_MAX_SAFE_INTEGER = (1 << 53) - 1
+_FORBIDDEN_ID_TOKENS = frozenset(
+    {
+        "latest",
+        "provider",
+        "source",
+        "broker",
+        "credential",
+        "locator",
+        "uri",
+        "s3",
+        "http",
+        "file",
+        "postgres",
+        "mysql",
+        "clickhouse",
+        "table",
+        "sql",
+        "tushare",
+        "wind",
+        "bloomberg",
+        "qtdb",
+        "edb",
+        "db",
+        "database",
+        "schema",
+        "bucket",
+        "path",
+        "endpoint",
+    }
+)
 
 __all__ = [
+    "BACKTEST_RUN_REF_SCHEMA_VERSION",
     "DatasetSnapshot",
     "FactorVersion",
     "bind_legacy_factor",
@@ -39,6 +86,9 @@ __all__ = [
     "StrategyStage",
     "StrategyVersion",
     "BacktestRun",
+    "BacktestContractErrorCode",
+    "BacktestContractError",
+    "BacktestRunRef",
     "PortfolioTarget",
     "RiskPolicy",
     "RiskDecisionStatus",
@@ -51,6 +101,684 @@ __all__ = [
 ]
 
 
+BACKTEST_RUN_REF_SCHEMA_VERSION = "1.0.0"
+
+
+class BacktestContractErrorCode(StrEnum):
+    """Stable rejection categories shared by the S3 public contracts."""
+
+    TYPE_ERROR = "type_error"
+    MISSING_FIELD = "missing_field"
+    UNKNOWN_FIELD = "unknown_field"
+    INVALID_FORMAT = "invalid_format"
+    INVALID_VALUE = "invalid_value"
+    IDENTITY_MISMATCH = "identity_mismatch"
+    QUALIFICATION_REJECTED = "qualification_rejected"
+    TIME_ORDER_VIOLATION = "time_order_violation"
+    INPUT_CLOSURE_VIOLATION = "input_closure_violation"
+    LINEAGE_VIOLATION = "lineage_violation"
+    EVIDENCE_MISMATCH = "evidence_mismatch"
+    READINESS_ESCALATION = "readiness_escalation"
+
+
+class BacktestContractError(ValueError):
+    """Typed deterministic contract rejection with an exact JSON path."""
+
+    def __init__(self, code: BacktestContractErrorCode, path: str, detail: str) -> None:
+        self.code = code
+        self.path = path
+        self.detail = detail
+        super().__init__(f"{code.value} at {path}: {detail}")
+
+
+def _backtest_fail(
+    code: BacktestContractErrorCode,
+    path: str,
+    detail: str,
+) -> Never:
+    raise BacktestContractError(code, path, detail)
+
+
+def _backtest_object(value: Any, path: str, fields: Sequence[str]) -> dict[str, Any]:
+    if type(value) is not dict:
+        _backtest_fail(BacktestContractErrorCode.TYPE_ERROR, path, "must be an object")
+    if any(type(key) is not str for key in value):
+        _backtest_fail(
+            BacktestContractErrorCode.TYPE_ERROR,
+            path,
+            "object keys must be strings",
+        )
+    required = set(fields)
+    missing = sorted(required - set(value))
+    if missing:
+        _backtest_fail(
+            BacktestContractErrorCode.MISSING_FIELD,
+            f"{path}.{missing[0]}",
+            "field is required",
+        )
+    unknown = sorted(set(value) - required)
+    if unknown:
+        _backtest_fail(
+            BacktestContractErrorCode.UNKNOWN_FIELD,
+            f"{path}.{unknown[0]}",
+            "field is not permitted",
+        )
+    return value
+
+
+def _backtest_text(value: Any, path: str) -> str:
+    if type(value) is not str:
+        _backtest_fail(BacktestContractErrorCode.TYPE_ERROR, path, "must be a string")
+    try:
+        value.encode("utf-8")
+    except UnicodeEncodeError as error:
+        raise BacktestContractError(
+            BacktestContractErrorCode.INVALID_FORMAT,
+            path,
+            "must be valid UTF-8 text",
+        ) from error
+    if not value or value != value.strip():
+        _backtest_fail(
+            BacktestContractErrorCode.INVALID_FORMAT,
+            path,
+            "must be non-empty canonical text",
+        )
+    return value
+
+
+def _backtest_logical_id(value: Any, path: str) -> str:
+    logical_id = _backtest_text(value, path)
+    tokens = set(re.split(r"[._-]+", logical_id))
+    if _LOGICAL_ID.fullmatch(logical_id) is None or tokens & _FORBIDDEN_ID_TOKENS:
+        _backtest_fail(
+            BacktestContractErrorCode.INVALID_FORMAT,
+            path,
+            "must be a stable storage-neutral logical identifier",
+        )
+    return logical_id
+
+
+def _backtest_semver(value: Any, path: str) -> str:
+    version = _backtest_text(value, path)
+    if _SEMVER.fullmatch(version) is None:
+        _backtest_fail(
+            BacktestContractErrorCode.INVALID_FORMAT,
+            path,
+            "must be a canonical semantic version",
+        )
+    return version
+
+
+def _backtest_digest(value: Any, path: str) -> str:
+    digest = _backtest_text(value, path)
+    if _PREFIXED_SHA256.fullmatch(digest) is None:
+        _backtest_fail(
+            BacktestContractErrorCode.INVALID_FORMAT,
+            path,
+            "must be a lowercase sha256 digest",
+        )
+    return digest
+
+
+def _backtest_git_revision(value: Any, path: str) -> str:
+    revision = _backtest_text(value, path)
+    if _GIT_SHA.fullmatch(revision) is None:
+        _backtest_fail(
+            BacktestContractErrorCode.INVALID_FORMAT,
+            path,
+            "must be a lowercase 40-character Git commit",
+        )
+    return revision
+
+
+def _backtest_instant(value: Any, path: str) -> tuple[str, datetime]:
+    text = _backtest_text(value, path)
+    if not text.endswith("Z"):
+        _backtest_fail(
+            BacktestContractErrorCode.INVALID_FORMAT,
+            path,
+            "must be a canonical UTC instant",
+        )
+    try:
+        parsed = datetime.fromisoformat(text.removesuffix("Z") + "+00:00")
+    except ValueError as error:
+        raise BacktestContractError(
+            BacktestContractErrorCode.INVALID_FORMAT,
+            path,
+            "must be a canonical UTC instant",
+        ) from error
+    normalized = parsed.astimezone(UTC).isoformat().replace("+00:00", "Z")
+    if normalized != text:
+        _backtest_fail(
+            BacktestContractErrorCode.INVALID_FORMAT,
+            path,
+            "must be a canonical UTC instant",
+        )
+    return text, parsed
+
+
+def _backtest_integer(value: Any, path: str, *, minimum: int = 0) -> int:
+    if type(value) is not int:
+        _backtest_fail(BacktestContractErrorCode.TYPE_ERROR, path, "must be an integer")
+    if value < minimum:
+        _backtest_fail(
+            BacktestContractErrorCode.INVALID_VALUE,
+            path,
+            f"must be at least {minimum}",
+        )
+    if value > _MAX_SAFE_INTEGER:
+        _backtest_fail(
+            BacktestContractErrorCode.INVALID_VALUE,
+            path,
+            "integer exceeds the canonical safe range",
+        )
+    return value
+
+
+def _backtest_string_tuple(value: Any, path: str) -> tuple[str, ...]:
+    if type(value) not in {tuple, list}:
+        _backtest_fail(BacktestContractErrorCode.TYPE_ERROR, path, "must be an array")
+    normalized = tuple(
+        _backtest_text(item, f"{path}[{index}]") for index, item in enumerate(value)
+    )
+    if len(normalized) != len(set(normalized)):
+        _backtest_fail(
+            BacktestContractErrorCode.INVALID_VALUE,
+            path,
+            "items must be unique",
+        )
+    return tuple(sorted(normalized))
+
+
+def _content_address_digest(value: str, prefix: str, path: str) -> str:
+    if not value.startswith(prefix) or _SHA256.fullmatch(value.removeprefix(prefix)) is None:
+        _backtest_fail(
+            BacktestContractErrorCode.IDENTITY_MISMATCH,
+            path,
+            "authority identity is not content addressed",
+        )
+    return f"sha256:{value.removeprefix(prefix)}"
+
+
+def _digest_document(value: object) -> str:
+    return f"sha256:{hashlib.sha256(canonical_json_bytes(value)).hexdigest()}"
+
+
+def _selected_revision_closure(
+    foundation: DataFoundationEnvelope,
+    factor_set: FactorSetRef,
+    field: str,
+) -> tuple[str, ...]:
+    payload = foundation.to_dict()
+    raw_views = payload.get("standardized_views")
+    if type(raw_views) is not list:
+        _backtest_fail(
+            BacktestContractErrorCode.INPUT_CLOSURE_VIOLATION,
+            "$.foundation.standardized_views",
+            "validated Foundation views are required",
+        )
+    selected = set(factor_set.selected_view_ref_ids)
+    found: set[str] = set()
+    seen_views: set[str] = set()
+    for index, raw_view in enumerate(raw_views):
+        if type(raw_view) is not dict:
+            _backtest_fail(
+                BacktestContractErrorCode.INPUT_CLOSURE_VIOLATION,
+                f"$.foundation.standardized_views[{index}]",
+                "validated view object is required",
+            )
+        view_id = raw_view.get("view_ref_id")
+        if view_id not in selected:
+            continue
+        seen_views.add(str(view_id))
+        revisions = raw_view.get(field)
+        path = f"$.foundation.standardized_views[{index}].{field}"
+        if type(revisions) is not list:
+            _backtest_fail(
+                BacktestContractErrorCode.INPUT_CLOSURE_VIOLATION,
+                path,
+                "revision closure is required",
+            )
+        for revision_index, revision_id in enumerate(revisions):
+            found.add(_backtest_text(revision_id, f"{path}[{revision_index}]"))
+    if seen_views != selected:
+        _backtest_fail(
+            BacktestContractErrorCode.INPUT_CLOSURE_VIOLATION,
+            "$.factor_set.selected_view_ref_ids",
+            "selected FactorSet views are not Foundation members",
+        )
+    return tuple(sorted(found))
+
+
+@dataclass(frozen=True, slots=True, init=False)
+class BacktestRunRef:
+    """Immutable input/configuration/replay identity determined before output exists."""
+
+    contract_name: str
+    schema_version: str
+    run_id: str
+    dataset_snapshot_id: str
+    dataset_content_digest: str
+    dataset_manifest_digest: str
+    foundation_id: str
+    foundation_digest: str
+    factor_set_id: str
+    factor_set_digest: str
+    factor_output_content_digest: str
+    universe_digest: str
+    trading_calendar_revision_ids: tuple[str, ...]
+    trading_calendar_digest: str
+    corporate_action_revision_ids: tuple[str, ...]
+    corporate_action_digest: str
+    strategy_id: str
+    strategy_version: str
+    strategy_digest: str
+    execution_model_version: str
+    execution_model_digest: str
+    cost_model_version: str
+    cost_model_digest: str
+    random_seed: int
+    code_revision: str
+    environment_lock_digest: str
+    configuration_digest: str
+    evaluation_at: str
+    computed_at: str
+    replay_spec_digest: str
+    replay_parent_run_id: str | None
+    replay_reason: str | None
+    replay_attempt: int
+    replay_ancestor_run_ids: tuple[str, ...]
+
+    @classmethod
+    def create(
+        cls,
+        *,
+        dataset_snapshot: DatasetSnapshotEnvelope,
+        foundation: DataFoundationEnvelope,
+        factor_set: FactorSetRef,
+        universe_digest: str,
+        trading_calendar_revision_ids: Sequence[str],
+        corporate_action_revision_ids: Sequence[str],
+        strategy_id: str,
+        strategy_version: str,
+        strategy_digest: str,
+        execution_model_version: str,
+        execution_model_digest: str,
+        cost_model_version: str,
+        cost_model_digest: str,
+        random_seed: int,
+        code_revision: str,
+        environment_lock_digest: str,
+        configuration_digest: str,
+        evaluation_at: str,
+        computed_at: str,
+        parent: BacktestRunRef | None = None,
+        replay_reason: str | None = None,
+        replay_attempt: int = 0,
+    ) -> Self:
+        return cls._build(
+            dataset_snapshot=dataset_snapshot,
+            foundation=foundation,
+            factor_set=factor_set,
+            universe_digest=universe_digest,
+            trading_calendar_revision_ids=trading_calendar_revision_ids,
+            corporate_action_revision_ids=corporate_action_revision_ids,
+            strategy_id=strategy_id,
+            strategy_version=strategy_version,
+            strategy_digest=strategy_digest,
+            execution_model_version=execution_model_version,
+            execution_model_digest=execution_model_digest,
+            cost_model_version=cost_model_version,
+            cost_model_digest=cost_model_digest,
+            random_seed=random_seed,
+            code_revision=code_revision,
+            environment_lock_digest=environment_lock_digest,
+            configuration_digest=configuration_digest,
+            evaluation_at=evaluation_at,
+            computed_at=computed_at,
+            parent=parent,
+            replay_reason=replay_reason,
+            replay_attempt=replay_attempt,
+        )
+
+    @classmethod
+    def _build(
+        cls,
+        *,
+        dataset_snapshot: Any,
+        foundation: Any,
+        factor_set: Any,
+        universe_digest: Any,
+        trading_calendar_revision_ids: Any,
+        corporate_action_revision_ids: Any,
+        strategy_id: Any,
+        strategy_version: Any,
+        strategy_digest: Any,
+        execution_model_version: Any,
+        execution_model_digest: Any,
+        cost_model_version: Any,
+        cost_model_digest: Any,
+        random_seed: Any,
+        code_revision: Any,
+        environment_lock_digest: Any,
+        configuration_digest: Any,
+        evaluation_at: Any,
+        computed_at: Any,
+        parent: BacktestRunRef | None,
+        replay_reason: Any,
+        replay_attempt: Any,
+    ) -> Self:
+        if not isinstance(dataset_snapshot, DatasetSnapshotEnvelope):
+            _backtest_fail(
+                BacktestContractErrorCode.TYPE_ERROR,
+                "$.dataset_snapshot",
+                "complete validated DatasetSnapshotEnvelope required",
+            )
+        if not isinstance(foundation, DataFoundationEnvelope):
+            _backtest_fail(
+                BacktestContractErrorCode.TYPE_ERROR,
+                "$.foundation",
+                "complete validated DataFoundationEnvelope required",
+            )
+        if not isinstance(factor_set, FactorSetRef):
+            _backtest_fail(
+                BacktestContractErrorCode.TYPE_ERROR,
+                "$.factor_set",
+                "complete validated FactorSetRef required",
+            )
+        if foundation.dataset_snapshot_id != dataset_snapshot.snapshot_id:
+            _backtest_fail(
+                BacktestContractErrorCode.INPUT_CLOSURE_VIOLATION,
+                "$.foundation.dataset_snapshot_id",
+                "Foundation snapshot mismatch",
+            )
+        if (
+            factor_set.dataset_snapshot_id != dataset_snapshot.snapshot_id
+            or factor_set.foundation_id != foundation.foundation_id
+            or factor_set.upstream_evidence.snapshot_content_digest
+            != dataset_snapshot.content_digest
+            or factor_set.upstream_evidence.snapshot_manifest_digest
+            != dataset_snapshot.manifest_digest
+        ):
+            _backtest_fail(
+                BacktestContractErrorCode.INPUT_CLOSURE_VIOLATION,
+                "$.factor_set",
+                "FactorSet upstream authority mismatch",
+            )
+        expected_calendars = _selected_revision_closure(
+            foundation,
+            factor_set,
+            "trading_calendar_revision_ids",
+        )
+        supplied_calendars = _backtest_string_tuple(
+            trading_calendar_revision_ids,
+            "$.trading_calendar_revision_ids",
+        )
+        if not expected_calendars or supplied_calendars != expected_calendars:
+            _backtest_fail(
+                BacktestContractErrorCode.INPUT_CLOSURE_VIOLATION,
+                "$.trading_calendar_revision_ids",
+                "must exactly match selected FactorSet calendar ancestry",
+            )
+        expected_actions = _selected_revision_closure(
+            foundation,
+            factor_set,
+            "corporate_action_revision_ids",
+        )
+        supplied_actions = _backtest_string_tuple(
+            corporate_action_revision_ids,
+            "$.corporate_action_revision_ids",
+        )
+        if supplied_actions != expected_actions:
+            _backtest_fail(
+                BacktestContractErrorCode.INPUT_CLOSURE_VIOLATION,
+                "$.corporate_action_revision_ids",
+                "must exactly match selected FactorSet corporate-action ancestry",
+            )
+
+        normalized_evaluation, evaluation_time = _backtest_instant(
+            evaluation_at,
+            "$.evaluation_at",
+        )
+        normalized_computed, computed_time = _backtest_instant(computed_at, "$.computed_at")
+        _, factor_available = _backtest_instant(
+            factor_set.artifact_available_at,
+            "$.factor_set.artifact_available_at",
+        )
+        _, factor_evaluation = _backtest_instant(
+            factor_set.evaluation_at,
+            "$.factor_set.evaluation_at",
+        )
+        if evaluation_time < factor_evaluation or evaluation_time < factor_available:
+            _backtest_fail(
+                BacktestContractErrorCode.TIME_ORDER_VIOLATION,
+                "$.evaluation_at",
+                "run evaluation must not precede FactorSet evaluation or availability",
+            )
+        if computed_time < evaluation_time or computed_time < factor_available:
+            _backtest_fail(
+                BacktestContractErrorCode.TIME_ORDER_VIOLATION,
+                "$.computed_at",
+                "FactorSet availability and evaluation must not follow computation",
+            )
+
+        normalized_seed = _backtest_integer(random_seed, "$.random_seed")
+        replay_count = _backtest_integer(replay_attempt, "$.replay_attempt")
+        spec_payload: dict[str, object] = {
+            "dataset_snapshot_id": dataset_snapshot.snapshot_id,
+            "dataset_content_digest": dataset_snapshot.content_digest,
+            "dataset_manifest_digest": dataset_snapshot.manifest_digest,
+            "foundation_id": foundation.foundation_id,
+            "foundation_digest": _content_address_digest(
+                foundation.foundation_id,
+                "rhdfv1:sha256:",
+                "$.foundation.foundation_id",
+            ),
+            "factor_set_id": factor_set.factor_set_id,
+            "factor_set_digest": _content_address_digest(
+                factor_set.factor_set_id,
+                "rhfactorsetv1:sha256:",
+                "$.factor_set.factor_set_id",
+            ),
+            "factor_output_content_digest": factor_set.output_content_digest,
+            "universe_digest": _backtest_digest(universe_digest, "$.universe_digest"),
+            "trading_calendar_revision_ids": list(supplied_calendars),
+            "trading_calendar_digest": _digest_document(list(supplied_calendars)),
+            "corporate_action_revision_ids": list(supplied_actions),
+            "corporate_action_digest": _digest_document(list(supplied_actions)),
+            "strategy_id": _backtest_logical_id(strategy_id, "$.strategy_id"),
+            "strategy_version": _backtest_semver(strategy_version, "$.strategy_version"),
+            "strategy_digest": _backtest_digest(strategy_digest, "$.strategy_digest"),
+            "execution_model_version": _backtest_semver(
+                execution_model_version,
+                "$.execution_model_version",
+            ),
+            "execution_model_digest": _backtest_digest(
+                execution_model_digest,
+                "$.execution_model_digest",
+            ),
+            "cost_model_version": _backtest_semver(cost_model_version, "$.cost_model_version"),
+            "cost_model_digest": _backtest_digest(
+                cost_model_digest,
+                "$.cost_model_digest",
+            ),
+            "random_seed": normalized_seed,
+            "code_revision": _backtest_git_revision(code_revision, "$.code_revision"),
+            "environment_lock_digest": _backtest_digest(
+                environment_lock_digest,
+                "$.environment_lock_digest",
+            ),
+            "configuration_digest": _backtest_digest(
+                configuration_digest,
+                "$.configuration_digest",
+            ),
+            "evaluation_at": normalized_evaluation,
+        }
+        replay_spec_digest = _digest_document(spec_payload)
+        if parent is None:
+            if replay_reason is not None:
+                _backtest_fail(
+                    BacktestContractErrorCode.LINEAGE_VIOLATION,
+                    "$.replay_reason",
+                    "root run cannot declare a replay reason",
+                )
+            if replay_count != 0:
+                _backtest_fail(
+                    BacktestContractErrorCode.LINEAGE_VIOLATION,
+                    "$.replay_attempt",
+                    "root run must use attempt zero",
+                )
+            normalized_reason = None
+            parent_run_id = None
+            ancestors: tuple[str, ...] = ()
+        else:
+            if not isinstance(parent, BacktestRunRef):
+                _backtest_fail(
+                    BacktestContractErrorCode.TYPE_ERROR,
+                    "$.parent",
+                    "BacktestRunRef parent is required",
+                )
+            normalized_reason = _backtest_logical_id(replay_reason, "$.replay_reason")
+            if replay_count != parent.replay_attempt + 1:
+                _backtest_fail(
+                    BacktestContractErrorCode.LINEAGE_VIOLATION,
+                    "$.replay_attempt",
+                    "replay attempt must follow its parent",
+                )
+            if replay_spec_digest != parent.replay_spec_digest:
+                _backtest_fail(
+                    BacktestContractErrorCode.LINEAGE_VIOLATION,
+                    "$.replay_spec_digest",
+                    "replay cannot claim changed deterministic inputs",
+                )
+            _, parent_computed = _backtest_instant(parent.computed_at, "$.parent.computed_at")
+            if computed_time <= parent_computed:
+                _backtest_fail(
+                    BacktestContractErrorCode.TIME_ORDER_VIOLATION,
+                    "$.computed_at",
+                    "replay computation must follow its parent",
+                )
+            parent_run_id = parent.run_id
+            ancestors = (*parent.replay_ancestor_run_ids, parent.run_id)
+            if len(ancestors) != len(set(ancestors)):
+                _backtest_fail(
+                    BacktestContractErrorCode.LINEAGE_VIOLATION,
+                    "$.replay_ancestor_run_ids",
+                    "replay lineage contains a cycle",
+                )
+
+        payload: dict[str, object] = {
+            "contract_name": "researchhub.backtest-run-ref",
+            "schema_version": BACKTEST_RUN_REF_SCHEMA_VERSION,
+            **spec_payload,
+            "computed_at": normalized_computed,
+            "replay_spec_digest": replay_spec_digest,
+            "replay_parent_run_id": parent_run_id,
+            "replay_reason": normalized_reason,
+            "replay_attempt": replay_count,
+            "replay_ancestor_run_ids": list(ancestors),
+        }
+        run_id = f"rhbacktestrunv1:sha256:{hashlib.sha256(canonical_json_bytes(payload)).hexdigest()}"
+        values: dict[str, object] = {
+            **payload,
+            "run_id": run_id,
+            "trading_calendar_revision_ids": supplied_calendars,
+            "corporate_action_revision_ids": supplied_actions,
+            "replay_ancestor_run_ids": ancestors,
+        }
+        instance = object.__new__(cls)
+        for name, value in values.items():
+            object.__setattr__(instance, name, value)
+        return instance
+
+    def to_dict(self) -> dict[str, Any]:
+        return {
+            "contract_name": self.contract_name,
+            "schema_version": self.schema_version,
+            "run_id": self.run_id,
+            "dataset_snapshot_id": self.dataset_snapshot_id,
+            "dataset_content_digest": self.dataset_content_digest,
+            "dataset_manifest_digest": self.dataset_manifest_digest,
+            "foundation_id": self.foundation_id,
+            "foundation_digest": self.foundation_digest,
+            "factor_set_id": self.factor_set_id,
+            "factor_set_digest": self.factor_set_digest,
+            "factor_output_content_digest": self.factor_output_content_digest,
+            "universe_digest": self.universe_digest,
+            "trading_calendar_revision_ids": list(self.trading_calendar_revision_ids),
+            "trading_calendar_digest": self.trading_calendar_digest,
+            "corporate_action_revision_ids": list(self.corporate_action_revision_ids),
+            "corporate_action_digest": self.corporate_action_digest,
+            "strategy_id": self.strategy_id,
+            "strategy_version": self.strategy_version,
+            "strategy_digest": self.strategy_digest,
+            "execution_model_version": self.execution_model_version,
+            "execution_model_digest": self.execution_model_digest,
+            "cost_model_version": self.cost_model_version,
+            "cost_model_digest": self.cost_model_digest,
+            "random_seed": self.random_seed,
+            "code_revision": self.code_revision,
+            "environment_lock_digest": self.environment_lock_digest,
+            "configuration_digest": self.configuration_digest,
+            "evaluation_at": self.evaluation_at,
+            "computed_at": self.computed_at,
+            "replay_spec_digest": self.replay_spec_digest,
+            "replay_parent_run_id": self.replay_parent_run_id,
+            "replay_reason": self.replay_reason,
+            "replay_attempt": self.replay_attempt,
+            "replay_ancestor_run_ids": list(self.replay_ancestor_run_ids),
+        }
+
+    def to_json(self) -> str:
+        return canonical_json(self.to_dict())
+
+    @classmethod
+    def from_dict(
+        cls,
+        value: Any,
+        *,
+        dataset_snapshot: DatasetSnapshotEnvelope,
+        foundation: DataFoundationEnvelope,
+        factor_set: FactorSetRef,
+        parent: BacktestRunRef | None = None,
+    ) -> Self:
+        field_names = tuple(cls.__dataclass_fields__)
+        item = _backtest_object(value, "$", field_names)
+        rebuilt = cls._build(
+            dataset_snapshot=dataset_snapshot,
+            foundation=foundation,
+            factor_set=factor_set,
+            universe_digest=item["universe_digest"],
+            trading_calendar_revision_ids=item["trading_calendar_revision_ids"],
+            corporate_action_revision_ids=item["corporate_action_revision_ids"],
+            strategy_id=item["strategy_id"],
+            strategy_version=item["strategy_version"],
+            strategy_digest=item["strategy_digest"],
+            execution_model_version=item["execution_model_version"],
+            execution_model_digest=item["execution_model_digest"],
+            cost_model_version=item["cost_model_version"],
+            cost_model_digest=item["cost_model_digest"],
+            random_seed=item["random_seed"],
+            code_revision=item["code_revision"],
+            environment_lock_digest=item["environment_lock_digest"],
+            configuration_digest=item["configuration_digest"],
+            evaluation_at=item["evaluation_at"],
+            computed_at=item["computed_at"],
+            parent=parent,
+            replay_reason=item["replay_reason"],
+            replay_attempt=item["replay_attempt"],
+        )
+        expected = rebuilt.to_dict()
+        for name in field_names:
+            if item[name] != expected[name]:
+                _backtest_fail(
+                    BacktestContractErrorCode.IDENTITY_MISMATCH,
+                    f"$.{name}",
+                    "serialized run reference does not match admitted authorities",
+                )
+        return rebuilt
+
+
 def _required_text(value: str, name: str) -> str:
     normalized = value.strip()
     if not normalized:

tests/fixtures/backtest-evidence-v1.golden.json

@@ -0,0 +1,17 @@
+{
+  "run_id": "rhbacktestrunv1:sha256:5036c771c44a2adade9ea590eee0d8cf824ff8f519fadd8ba424e5d914856386",
+  "replay_spec_digest": "sha256:20f07fcb526bc38b4ba3d71d6c3b00a8c63ad96cab0fecd869326503ab42d98b",
+  "manifest_id": "rhbacktestevidencev1:sha256:f94733e849433f62f3da1e1ec8999891b93d49c7d657832d64e64bef9e211117",
+  "evidence_digest": "sha256:f3913894d032c389c64eef59058b3cbc694cb9cc14ce9cee2699f0068200b650",
+  "table_content_digests": {
+    "run": "sha256:7d947ec93f714641669cbb14bd69dd8cf30387aabb7f3a086918fc2e878ab05c",
+    "signals": "sha256:72dc15064cc45d7c51d2dd4b8c3a6d8c7d4155232d5d70d3c9e7697fab70ce50",
+    "trades": "sha256:2b8b9321e7993941ac486cf50cab5b4c6425b2571a4701f0eb02273ec9a96c53",
+    "positions": "sha256:b456a48fab51742b05084ca6dcaf01c03dfe5b39ad71215ada070e9b1f59f7ea",
+    "nav": "sha256:25649efce860b76410f87dbd36c81085887620086dc0b48b07099918f65d9c78",
+    "performance": "sha256:0856439ea7ec84e38887ccfa0067324f2e9cd293543e4ef683b9c2beb9eb34cf",
+    "attribution": "sha256:ad0f12f668d0a2d9ae5b3636d29989ab4bafcfb95f5de77abeb52a6d9e95d366",
+    "attribution_daily": "sha256:d4459ad650f88871d7b1e40392033037b5818ef92fdf1ee021868929fc1455a5",
+    "risk": "sha256:4816dd4812b5ff2e97e74bf34ca2221bfde675b387a96e277683557f0ad7d975"
+  }
+}

tests/fixtures/portfolio-risk-computation-v1.golden.json

@@ -0,0 +1,129 @@
+{
+  "portfolio_decision": {
+    "computed_at": "2026-01-08T03:01:00Z",
+    "constraint_residuals": {
+      "gross_exposure_max": 0.0,
+      "net_exposure_max": 0.0,
+      "net_exposure_min": 0.0,
+      "position_count_max": 0.0,
+      "single_asset_max": 0.0,
+      "single_asset_min": 0.0,
+      "turnover_max": 0.0
+    },
+    "constraints": {
+      "gross_exposure_max": 1.0,
+      "net_exposure_max": 1.0,
+      "net_exposure_min": 1.0,
+      "position_count_max": 2,
+      "schema_version": "1.0.0",
+      "single_asset_max": 0.7,
+      "single_asset_min": 0.2,
+      "turnover_max": 0.2
+    },
+    "contract_name": "researchhub.portfolio-decision",
+    "covariance_digest": "sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+    "dataset_snapshot_id": "rhdsv1:sha256:f63a29b4795c63fb7d6b2d3b5544cee9274b633db77c75c63d50a340c0827d57",
+    "decision_id": "rhportfoliodecisionv1:sha256:0e6e5ce2fa08de8006cc392610695a013327fc80645bfa4d7a908ad3f615bebd",
+    "effective_at": "2026-01-08T03:00:00Z",
+    "evidence_digest": "sha256:f3913894d032c389c64eef59058b3cbc694cb9cc14ce9cee2699f0068200b650",
+    "expected_return_digest": "sha256:dddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddd",
+    "freshness_policy": {
+      "max_covariance_age_days": 0,
+      "max_manifest_age_seconds": 3600,
+      "schema_version": "1.0.0"
+    },
+    "gross_exposure": 1.0,
+    "manifest_document_sha256": "fbf54218f770528978f9ccd35577e1ab00877143ea397a576e071e75f0afbab0",
+    "manifest_id": "rhbacktestevidencev1:sha256:681c49cbdfb3e221b273e7bc616602ad80a7ab01206970807ad4294b176ebc75",
+    "model_digest": "sha256:cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc",
+    "model_name": "deterministic_weights",
+    "model_version": "1.0.0",
+    "net_exposure": 1.0,
+    "objective_digest": "sha256:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb",
+    "objective_name": "long_only_allocation",
+    "objective_version": "1.0.0",
+    "output_digest": "sha256:bd3b964c628c8648322d036e57dd6f444ca287017d1578bab3689d07d32b28ce",
+    "portfolio_asset_set_digest": "sha256:b64e3448a83a5b86466465080361c1a7e1157a27ddccd4b68069cb18caffb74a",
+    "position_count": 2,
+    "prior_weights": {
+      "A": 0.5,
+      "B": 0.5
+    },
+    "receipt": {
+      "algorithm": "bounded_allocation",
+      "algorithm_version": "1.0.0",
+      "computed_at": "2026-01-08T03:01:00Z",
+      "constraint_digest": "sha256:34df0e5c00f503748ff936f9cd415a8947169181f8ca0917bce97dd606e08e94",
+      "implementation_digest": "sha256:ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
+      "input_digest": "sha256:ebd8ff957115e1adfd84eafa5cea49470356194d747b64ee5897858f9dd067b7",
+      "iterations": null,
+      "max_constraint_residual": 0.0,
+      "objective_value": null,
+      "output_digest": "sha256:bd3b964c628c8648322d036e57dd6f444ca287017d1578bab3689d07d32b28ce",
+      "parameter_digest": "sha256:0000000000000000000000000000000000000000000000000000000000000000",
+      "schema_version": "1.0.0",
+      "solver_config_digest": null,
+      "solver_name": null,
+      "solver_required": false,
+      "solver_version": null,
+      "status": "completed",
+      "tolerance": 1e-12
+    },
+    "run_id": "rhbacktestrunv1:sha256:5036c771c44a2adade9ea590eee0d8cf824ff8f519fadd8ba424e5d914856386",
+    "run_ref_document_sha256": "6a798adb3e0568aca84ed3e3a285b92d181ec569462fc003952a8c0d8382ae3a",
+    "scenario_digest": "sha256:eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee",
+    "schema_version": "1.0.0",
+    "source_universe_digest": "sha256:5555555555555555555555555555555555555555555555555555555555555555",
+    "target_id": "portfolio-target:synthetic-v1",
+    "target_weights": {
+      "A": 0.6,
+      "B": 0.4
+    },
+    "turnover_l1": 0.19999999999999996
+  },
+  "risk_assessment": {
+    "assessment_id": "rhriskassessmentv1:sha256:dbc38825cffcf6d95bd0216d22dbba4e0d4a1359ca5924a3ee529b99a7d78b6d",
+    "component_risk": {
+      "A": 1.4549226783578566,
+      "B": 1.4549226783578568
+    },
+    "contract_name": "researchhub.risk-assessment",
+    "covariance_as_of_date": "2026-01-08",
+    "covariance_data_snapshot_id": "rhdsv1:sha256:f63a29b4795c63fb7d6b2d3b5544cee9274b633db77c75c63d50a340c0827d57",
+    "covariance_input_digest": "sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+    "covariance_snapshot_id": "covariance:synthetic-v1",
+    "dataset_snapshot_id": "rhdsv1:sha256:f63a29b4795c63fb7d6b2d3b5544cee9274b633db77c75c63d50a340c0827d57",
+    "decision_id": "rhportfoliodecisionv1:sha256:0e6e5ce2fa08de8006cc392610695a013327fc80645bfa4d7a908ad3f615bebd",
+    "findings": [],
+    "freshness_policy_digest": "sha256:833f58f4d1056f0450f7369fd4edd70534cc74e9e55cd60f05b2b3d7a2979763",
+    "group_exposure": {
+      "equity": 1.4549226783578566,
+      "fixed_income": 1.4549226783578568
+    },
+    "manifest_id": "rhbacktestevidencev1:sha256:681c49cbdfb3e221b273e7bc616602ad80a7ab01206970807ad4294b176ebc75",
+    "marginal_risk": {
+      "A": 2.424871130596428,
+      "B": 3.637306695894642
+    },
+    "percentage_risk": {
+      "A": 0.49999999999999983,
+      "B": 0.49999999999999994
+    },
+    "periods_per_year": 252,
+    "portfolio_volatility": 2.909845356715714,
+    "portfolio_volatility_limit": 10.0,
+    "qualified": true,
+    "return_frequency": "1d",
+    "risk_budget": {
+      "A": 0.8,
+      "B": 0.8
+    },
+    "risk_model_digest": "sha256:2222222222222222222222222222222222222222222222222222222222222222",
+    "risk_model_name": "euler_volatility",
+    "risk_model_version": "1.0.0",
+    "run_id": "rhbacktestrunv1:sha256:5036c771c44a2adade9ea590eee0d8cf824ff8f519fadd8ba424e5d914856386",
+    "scenario_digest": "sha256:eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee",
+    "schema_version": "1.0.0",
+    "status": "ready"
+  }
+}

tests/governance/test_module_spec.py

@@ -16,19 +16,30 @@ def test_module_spec_declares_pure_research_engine_boundary() -> None:
     prohibited = " ".join(spec["bounded_context"]["prohibited_responsibilities"]).lower()
     for term in ("investment advice", "live order", "credentials", "source facts"):
         assert term in prohibited
-    assert spec["authority"]["revision"] == 2
+    assert spec["authority"]["revision"] == 4
     assert {
         (item["contract_id"], item["version"])
         for item in spec["contracts"]["provides"]
     } == {
         ("researchhub.factor-definition", "1.0.0"),
         ("researchhub.factor-set-ref", "1.0.0"),
+        ("researchhub.backtest-run-ref", "1.0.0"),
+        ("researchhub.backtest-evidence-manifest", "1.0.0"),
+        ("researchhub.portfolio-decision", "1.0.0"),
+        ("researchhub.risk-assessment", "1.0.0"),
     }
-    assert all(
+    expected_paths = {
-        item["authority"] == "quant_engine"
+        "researchhub.factor-definition": "src/quant_engine/factor_contracts.py",
-        and item["path"] == "src/quant_engine/factor_contracts.py"
+        "researchhub.factor-set-ref": "src/quant_engine/factor_contracts.py",
-        for item in spec["contracts"]["provides"]
+        "researchhub.backtest-run-ref": "src/quant_engine/governed_pipeline.py",
-    )
+        "researchhub.backtest-evidence-manifest": "src/quant_engine/artifact.py",
+        "researchhub.portfolio-decision": "src/quant_engine/portfolio_risk_contracts.py",
+        "researchhub.risk-assessment": "src/quant_engine/portfolio_risk_contracts.py",
+    }
+    assert all(item["authority"] == "quant_engine" for item in spec["contracts"]["provides"])
+    assert {
+        item["contract_id"]: item["path"] for item in spec["contracts"]["provides"]
+    } == expected_paths
     assert {
         (item["contract_id"], item["version"])
         for item in spec["contracts"]["consumes"]
@@ -41,6 +52,14 @@ def test_module_spec_declares_pure_research_engine_boundary() -> None:
         for item in spec["contracts"]["consumes"]
     )
     assert spec["dependencies"] == []
+    capabilities = {item["id"]: item for item in spec["capabilities"]}
+    portfolio_contract = capabilities["portfolio-risk-computation-contracts"]
+    assert portfolio_contract["status"] == "operational"
+    summary = portfolio_contract["summary"].lower()
+    for term in ("receipt", "portfolio decisions", "risk assessments", "without"):
+        assert term in summary
+    for term in ("approval", "maker-checker", "publication", "paper", "live"):
+        assert term in prohibited
     assert all(
         command["required"] and not command["network"]
         for command in spec["verification"]["commands"]

tests/test_backtest_contracts.py

@@ -0,0 +1,773 @@
+"""Backtest run-reference and closed-evidence contract conformance."""
+
+from __future__ import annotations
+
+import copy
+import hashlib
+import json
+from dataclasses import replace
+from datetime import UTC, datetime
+from pathlib import Path
+from typing import Any
+
+import pandas as pd
+import pytest
+
+from quant_engine.artifact import (
+    BacktestEvidenceManifest,
+    EvidenceQualification,
+    RESEARCH_ARTIFACT_SCHEMA_VERSION,
+    ResearchRunArtifact,
+    build_backtest_evidence_manifest,
+    build_legacy_backtest_evidence_manifest,
+    build_research_run_artifact,
+)
+from quant_engine.execution import ExecutionConfig
+from quant_engine.factor_contracts import (
+    ActorIdentity,
+    AvailabilityMode,
+    Causation,
+    DataFoundationEnvelope,
+    DatasetSnapshotEnvelope,
+    FactorInput,
+    FactorSetRef,
+    InputBinding,
+    OutputArtifactRef,
+    OutputCoverage,
+    OutputQuality,
+    OutputQualityCheck,
+    ProducerIdentity,
+    ViewAvailability,
+    canonical_json_bytes,
+    factor_definition_from_alpha158,
+    factor_input_schema_digest,
+)
+from quant_engine.governed_pipeline import (
+    BacktestContractError,
+    BacktestContractErrorCode,
+    BacktestRun,
+    BacktestRunRef,
+)
+from quant_engine.research_pipeline import FactorBacktestResult, run_factor_backtest_research
+
+
+ROOT = Path(__file__).resolve().parents[1]
+FACTOR_FIXTURE = ROOT / "tests" / "fixtures" / "factor-contracts-v1.golden.json"
+BACKTEST_FIXTURE = ROOT / "tests" / "fixtures" / "backtest-evidence-v1.golden.json"
+VIEW_REF_ID = "rhviewrefv1:sha256:bf776bcd26d940fafde1d650776a5505fb3fe8b5b068c351622bf2c42385629c"
+VIEW_SCHEMA_DIGEST = "sha256:0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef"
+CALENDAR_REVISION_ID = "rhcalv1:sha256:1f4ca22557063389badd669cf774bb35234066e847646682dccfe411e252a078"
+ACTION_REVISION_ID = "rhcav1:sha256:0f947df29f152bfa2c6ab0da7a0d464670c7ad2526cd10f2a7939b42fee5c275"
+PARAMETERS = {"lag_sessions": 1, "top_k": 1}
+
+
+def _sha256(value: bytes) -> str:
+    return f"sha256:{hashlib.sha256(value).hexdigest()}"
+
+
+def _accepted_authorities(
+    *,
+    factor_evaluation_at: str = "2026-01-03T11:00:00Z",
+    factor_computed_at: str = "2026-01-03T10:15:00Z",
+    factor_artifact_available_at: str = "2026-01-03T10:20:00Z",
+    factor_availability_mode: AvailabilityMode = AvailabilityMode.AS_AVAILABLE,
+) -> tuple[
+    DatasetSnapshotEnvelope,
+    DataFoundationEnvelope,
+    FactorSetRef,
+]:
+    fixture = json.loads(FACTOR_FIXTURE.read_text(encoding="utf-8"))
+    snapshot = DatasetSnapshotEnvelope.from_dict(fixture["dataset_snapshot"])
+    foundation = DataFoundationEnvelope.from_dict(fixture["data_foundation"])
+    factor_input = FactorInput("market", VIEW_SCHEMA_DIGEST, ("close", "volume"))
+    definition = factor_definition_from_alpha158(
+        "alpha_005",
+        version="1.0.0",
+        parameters={},
+        inputs=(factor_input,),
+        implementation_digest="sha256:" + "1" * 64,
+        input_schema_digest=factor_input_schema_digest((factor_input,)),
+        valid_from="2026-01-01T00:00:00.000000Z",
+        valid_until="2027-01-01T00:00:00Z",
+        warmup_sessions=10,
+        lag_sessions=1,
+        producer=ProducerIdentity("quant_engine", "1.0.0"),
+        code_revision="c" * 40,
+    )
+    output_schema_bytes = canonical_json_bytes(fixture["output_schema"])
+    output_content_bytes = canonical_json_bytes(fixture["output_content"])
+    artifact_ref = OutputArtifactRef.create(
+        schema_digest=_sha256(output_schema_bytes),
+        content_digest=_sha256(output_content_bytes),
+    )
+    factor_set = FactorSetRef.create(
+        definitions=(definition,),
+        dataset_snapshot=snapshot,
+        foundation=foundation,
+        selected_view_ref_ids=(VIEW_REF_ID,),
+        input_bindings=(
+            InputBinding(definition.definition_id, "market", VIEW_REF_ID, VIEW_SCHEMA_DIGEST),
+        ),
+        view_availability=(
+            ViewAvailability(VIEW_REF_ID, "2026-01-02T23:50:00Z", "sha256:" + "2" * 64),
+        ),
+        output_quality=OutputQuality(
+            "passed",
+            (OutputQualityCheck("finite_values", "passed", "sha256:" + "3" * 64),),
+        ),
+        output_coverage=OutputCoverage(
+            "complete", 1, 1, "row", "alpha_005.cn_a", "sha256:" + "4" * 64
+        ),
+        output_schema_bytes=output_schema_bytes,
+        output_content_bytes=output_content_bytes,
+        output_artifact_ref=artifact_ref,
+        availability_mode=factor_availability_mode,
+        evaluation_at=factor_evaluation_at,
+        computed_at=factor_computed_at,
+        artifact_available_at=factor_artifact_available_at,
+        producer=ProducerIdentity("quant_engine", "1.0.0"),
+        code_revision="c" * 40,
+        actor=ActorIdentity("service", "factor_worker_v1"),
+        correlation_id="research_run_001",
+        causation=Causation("foundation", foundation.foundation_id),
+        evidence_scope="synthetic_fixture",
+        decision_eligible=False,
+    )
+    return snapshot, foundation, factor_set
+
+
+def _config_digest(parameters: dict[str, object] | None = None) -> str:
+    encoded = json.dumps(
+        PARAMETERS if parameters is None else parameters,
+        ensure_ascii=False,
+        sort_keys=True,
+        separators=(",", ":"),
+        allow_nan=False,
+    ).encode("utf-8")
+    return _sha256(encoded)
+
+
+def _run_ref(**overrides: Any) -> BacktestRunRef:
+    snapshot, foundation, factor_set = _accepted_authorities()
+    arguments: dict[str, Any] = {
+        "dataset_snapshot": snapshot,
+        "foundation": foundation,
+        "factor_set": factor_set,
+        "universe_digest": "sha256:" + "5" * 64,
+        "trading_calendar_revision_ids": (CALENDAR_REVISION_ID,),
+        "corporate_action_revision_ids": (ACTION_REVISION_ID,),
+        "strategy_id": "alpha-top1",
+        "strategy_version": "1.0.0",
+        "strategy_digest": "sha256:" + "6" * 64,
+        "execution_model_version": "1.0.0",
+        "execution_model_digest": "sha256:" + "7" * 64,
+        "cost_model_version": "1.0.0",
+        "cost_model_digest": "sha256:" + "8" * 64,
+        "random_seed": 7,
+        "code_revision": "d" * 40,
+        "environment_lock_digest": "sha256:" + "9" * 64,
+        "configuration_digest": _config_digest(),
+        "evaluation_at": "2026-01-08T01:00:00Z",
+        "computed_at": "2026-01-08T02:00:00Z",
+    }
+    arguments.update(overrides)
+    return BacktestRunRef.create(**arguments)
+
+
+def _backtest_result() -> FactorBacktestResult:
+    dates = pd.date_range("2026-01-05", periods=4, freq="B")
+    scores = pd.DataFrame({"A": [2.0, 0.0], "B": [1.0, 3.0]}, index=dates[:2])
+    opens = pd.DataFrame(
+        {"A": [10.0, 10.0, 15.0, 15.0], "B": [20.0, 20.0, 20.0, 21.0]},
+        index=dates,
+    )
+    closes = pd.DataFrame(
+        {"A": [10.0, 12.0, 15.0, 15.0], "B": [20.0, 20.0, 18.0, 21.0]},
+        index=dates,
+    )
+    return run_factor_backtest_research(
+        scores,
+        opens,
+        closes,
+        top_k=1,
+        execution_price_field="open",
+        valuation_price_field="close",
+        initial_cash=1_000.0,
+        config=ExecutionConfig(
+            commission_bps=0,
+            stamp_tax_bps=0,
+            slippage_bps=0,
+            min_trade_amount=0,
+        ),
+    )
+
+
+def _artifact(run_ref: BacktestRunRef, *, run_id: str | None = None) -> ResearchRunArtifact:
+    result = _backtest_result()
+    benchmark = pd.Series(
+        [0.0, 0.01, -0.01, 0.02],
+        index=result.returns.index,
+        name="benchmark_return",
+    )
+    return build_research_run_artifact(
+        result,
+        run_id=run_ref.run_id if run_id is None else run_id,
+        strategy_id=run_ref.strategy_id,
+        strategy_name="Alpha Top 1",
+        strategy_version=run_ref.strategy_version,
+        engine_version="1.2.0",
+        code_revision=run_ref.code_revision,
+        data_snapshot_id=run_ref.dataset_snapshot_id,
+        calendar="CN-A",
+        timezone="Asia/Shanghai",
+        started_at="2026-01-08T10:00:00+08:00",
+        finished_at="2026-01-08T10:01:00+08:00",
+        parameters=PARAMETERS,
+        benchmark_id="000300.SH",
+        benchmark_returns=benchmark,
+    )
+
+
+def _assert_error(
+    error: pytest.ExceptionInfo[BacktestContractError],
+    code: BacktestContractErrorCode,
+    path: str,
+) -> None:
+    assert error.value.code is code
+    assert error.value.path == path
+
+
+def test_backtest_run_ref_is_deterministic_and_binds_only_opaque_authorities() -> None:
+    first = _run_ref()
+    second = _run_ref()
+
+    assert first == second
+    assert first.run_id.startswith("rhbacktestrunv1:sha256:")
+    assert first.replay_spec_digest.startswith("sha256:")
+    assert first.dataset_snapshot_id.startswith("rhdsv1:sha256:")
+    assert first.foundation_id.startswith("rhdfv1:sha256:")
+    assert first.factor_set_id.startswith("rhfactorsetv1:sha256:")
+    assert first.trading_calendar_revision_ids == (CALENDAR_REVISION_ID,)
+    assert first.corporate_action_revision_ids == (ACTION_REVISION_ID,)
+    assert first.replay_parent_run_id is None
+    assert first.replay_attempt == 0
+    assert first.replay_ancestor_run_ids == ()
+    snapshot, foundation, factor_set = _accepted_authorities()
+    assert BacktestRunRef.from_dict(
+        first.to_dict(),
+        dataset_snapshot=snapshot,
+        foundation=foundation,
+        factor_set=factor_set,
+    ) == first
+    forbidden = ("latest", "locator", "uri", "credential", "provider", "broker")
+    assert not any(token in first.to_json().lower() for token in forbidden)
+
+
+@pytest.mark.parametrize(
+    ("field", "value"),
+    [
+        ("universe_digest", "sha256:" + "a" * 64),
+        ("strategy_digest", "sha256:" + "b" * 64),
+        ("execution_model_digest", "sha256:" + "c" * 64),
+        ("cost_model_digest", "sha256:" + "e" * 64),
+        ("random_seed", 8),
+        ("code_revision", "e" * 40),
+        ("environment_lock_digest", "sha256:" + "f" * 64),
+        ("configuration_digest", "sha256:" + "0" * 64),
+        ("evaluation_at", "2026-01-08T01:00:01Z"),
+        ("computed_at", "2026-01-08T02:00:01Z"),
+    ],
+)
+def test_every_governed_run_input_mutation_changes_run_identity(
+    field: str,
+    value: object,
+) -> None:
+    assert _run_ref(**{field: value}).run_id != _run_ref().run_id
+
+
+def test_backtest_run_ref_rejects_unclosed_upstream_and_unsafe_scalars() -> None:
+    with pytest.raises(BacktestContractError) as wrong_calendar:
+        _run_ref(trading_calendar_revision_ids=())
+    _assert_error(
+        wrong_calendar,
+        BacktestContractErrorCode.INPUT_CLOSURE_VIOLATION,
+        "$.trading_calendar_revision_ids",
+    )
+    with pytest.raises(BacktestContractError) as wrong_action:
+        _run_ref(corporate_action_revision_ids=())
+    _assert_error(
+        wrong_action,
+        BacktestContractErrorCode.INPUT_CLOSURE_VIOLATION,
+        "$.corporate_action_revision_ids",
+    )
+    with pytest.raises(BacktestContractError) as bool_seed:
+        _run_ref(random_seed=True)
+    _assert_error(bool_seed, BacktestContractErrorCode.TYPE_ERROR, "$.random_seed")
+    with pytest.raises(BacktestContractError) as bad_revision:
+        _run_ref(code_revision="abc")
+    _assert_error(bad_revision, BacktestContractErrorCode.INVALID_FORMAT, "$.code_revision")
+    with pytest.raises(BacktestContractError) as bad_digest:
+        _run_ref(universe_digest="5" * 64)
+    _assert_error(bad_digest, BacktestContractErrorCode.INVALID_FORMAT, "$.universe_digest")
+    with pytest.raises(BacktestContractError) as lookahead:
+        _run_ref(computed_at="2026-01-08T00:59:59Z")
+    _assert_error(lookahead, BacktestContractErrorCode.TIME_ORDER_VIOLATION, "$.computed_at")
+    with pytest.raises(BacktestContractError) as factor_type:
+        _run_ref(factor_set="rhfactorsetv1:sha256:" + "0" * 64)
+    _assert_error(factor_type, BacktestContractErrorCode.TYPE_ERROR, "$.factor_set")
+
+
+@pytest.mark.parametrize(
+    ("factor_times", "expected_path"),
+    [
+        (
+            {
+                "factor_evaluation_at": "2026-01-08T01:00:01Z",
+                "factor_computed_at": "2026-01-08T00:59:59Z",
+                "factor_artifact_available_at": "2026-01-08T01:00:00Z",
+            },
+            "$.evaluation_at",
+        ),
+        (
+            {
+                "factor_evaluation_at": "2026-01-03T11:00:00Z",
+                "factor_computed_at": "2026-01-08T01:00:00Z",
+                "factor_artifact_available_at": "2026-01-08T01:00:01Z",
+                "factor_availability_mode": AvailabilityMode.RETROSPECTIVE_REPLAY,
+            },
+            "$.evaluation_at",
+        ),
+    ],
+)
+def test_run_ref_evaluation_closes_factor_pit(
+    factor_times: dict[str, Any],
+    expected_path: str,
+) -> None:
+    snapshot, foundation, factor_set = _accepted_authorities(**factor_times)
+
+    with pytest.raises(BacktestContractError) as lookahead:
+        _run_ref(
+            dataset_snapshot=snapshot,
+            foundation=foundation,
+            factor_set=factor_set,
+        )
+
+    _assert_error(
+        lookahead,
+        BacktestContractErrorCode.TIME_ORDER_VIOLATION,
+        expected_path,
+    )
+
+
+def test_run_ref_rejects_aliases_locators_unsafe_integers_and_invalid_text() -> None:
+    with pytest.raises(BacktestContractError) as mutable_alias:
+        _run_ref(strategy_id="latest")
+    _assert_error(
+        mutable_alias,
+        BacktestContractErrorCode.INVALID_FORMAT,
+        "$.strategy_id",
+    )
+    with pytest.raises(BacktestContractError) as physical_uri:
+        _run_ref(execution_model_version="s3://model-bucket/current")
+    _assert_error(
+        physical_uri,
+        BacktestContractErrorCode.INVALID_FORMAT,
+        "$.execution_model_version",
+    )
+    with pytest.raises(BacktestContractError) as unsafe_seed:
+        _run_ref(random_seed=2**53)
+    _assert_error(
+        unsafe_seed,
+        BacktestContractErrorCode.INVALID_VALUE,
+        "$.random_seed",
+    )
+    with pytest.raises(BacktestContractError) as invalid_unicode:
+        _run_ref(strategy_id="\ud800")
+    _assert_error(
+        invalid_unicode,
+        BacktestContractErrorCode.INVALID_FORMAT,
+        "$.strategy_id",
+    )
+
+    run_ref = _run_ref()
+    mixed_keys = run_ref.to_dict()
+    mixed_keys[1] = "not-a-contract-key"  # type: ignore[index]
+    snapshot, foundation, factor_set = _accepted_authorities()
+    with pytest.raises(BacktestContractError) as invalid_key:
+        BacktestRunRef.from_dict(
+            mixed_keys,
+            dataset_snapshot=snapshot,
+            foundation=foundation,
+            factor_set=factor_set,
+        )
+    _assert_error(invalid_key, BacktestContractErrorCode.TYPE_ERROR, "$")
+
+
+@pytest.mark.parametrize(
+    "physical_id",
+    ["db.table", "source_alpha", "wind.model", "qtdb_view", "bloomberg-signal"],
+)
+def test_run_ref_rejects_physical_terms_in_logical_ids(physical_id: str) -> None:
+    with pytest.raises(BacktestContractError) as physical:
+        _run_ref(strategy_id=physical_id)
+    _assert_error(
+        physical,
+        BacktestContractErrorCode.INVALID_FORMAT,
+        "$.strategy_id",
+    )
+
+
+@pytest.mark.parametrize("version", ["1.0.0-.", "1.0.0-foo..bar", "1.0.0-01"])
+def test_run_ref_requires_strict_semver_prerelease_identifiers(version: str) -> None:
+    with pytest.raises(BacktestContractError) as invalid:
+        _run_ref(strategy_version=version)
+    _assert_error(
+        invalid,
+        BacktestContractErrorCode.INVALID_FORMAT,
+        "$.strategy_version",
+    )
+
+    assert _run_ref(strategy_version="1.0.0-alpha.1").strategy_version == "1.0.0-alpha.1"
+
+
+def test_replay_lineage_is_acyclic_and_cannot_claim_changed_inputs() -> None:
+    parent = _run_ref()
+    replay = _run_ref(
+        computed_at="2026-01-08T03:00:00Z",
+        parent=parent,
+        replay_reason="deterministic_reproduction",
+        replay_attempt=1,
+    )
+
+    assert replay.run_id != parent.run_id
+    assert replay.replay_spec_digest == parent.replay_spec_digest
+    assert replay.replay_parent_run_id == parent.run_id
+    assert replay.replay_ancestor_run_ids == (parent.run_id,)
+
+    with pytest.raises(BacktestContractError) as changed_input:
+        _run_ref(
+            universe_digest="sha256:" + "a" * 64,
+            computed_at="2026-01-08T03:00:00Z",
+            parent=parent,
+            replay_reason="changed_universe",
+            replay_attempt=1,
+        )
+    _assert_error(
+        changed_input,
+        BacktestContractErrorCode.LINEAGE_VIOLATION,
+        "$.replay_spec_digest",
+    )
+    with pytest.raises(BacktestContractError) as skipped_attempt:
+        _run_ref(
+            computed_at="2026-01-08T03:00:00Z",
+            parent=parent,
+            replay_reason="skipped_attempt",
+            replay_attempt=2,
+        )
+    _assert_error(
+        skipped_attempt,
+        BacktestContractErrorCode.LINEAGE_VIOLATION,
+        "$.replay_attempt",
+    )
+
+
+def test_offline_research_manifest_closes_exact_existing_evidence_mapping() -> None:
+    run_ref = _run_ref()
+    artifact = _artifact(run_ref)
+    first = build_backtest_evidence_manifest(
+        run_ref,
+        artifact,
+        artifact_available_at="2026-01-08T02:05:00Z",
+        qualification=EvidenceQualification.CONTRACT_QUALIFIED,
+    )
+    second = build_backtest_evidence_manifest(
+        run_ref,
+        artifact,
+        artifact_available_at="2026-01-08T02:05:00Z",
+        qualification=EvidenceQualification.CONTRACT_QUALIFIED,
+    )
+
+    assert first == second
+    assert first.manifest_id.startswith("rhbacktestevidencev1:sha256:")
+    assert first.run_id == run_ref.run_id
+    assert first.profile == "offline_research_v1"
+    assert first.qualification is EvidenceQualification.CONTRACT_QUALIFIED
+    mapping = {
+        item.category: tuple(table.logical_name for table in item.tables)
+        for item in first.evidence
+    }
+    assert mapping == {
+        "run": ("run",),
+        "signal": ("signals",),
+        "fill": ("trades",),
+        "position_nav": ("positions", "nav"),
+        "performance": ("performance",),
+        "attribution": ("attribution", "attribution_daily"),
+        "risk_snapshot": ("risk",),
+        "replay": (),
+    }
+    assert "order" not in mapping
+    assert "rejection" not in mapping
+    risk = next(item for item in first.evidence if item.category == "risk_snapshot")
+    assert risk.tables[0].row_count == 0
+    assert risk.tables[0].schema_digest.startswith("sha256:")
+
+    changed_performance = artifact.performance
+    changed_performance.loc[0, "n_days"] += 1
+    changed_artifact = replace(artifact, _performance=changed_performance)
+    changed = build_backtest_evidence_manifest(
+        run_ref,
+        changed_artifact,
+        artifact_available_at="2026-01-08T02:05:00Z",
+    )
+    assert changed.manifest_id != first.manifest_id
+    assert run_ref.run_id == first.run_id == changed.run_id
+
+
+def test_manifest_rejects_missing_mismatched_or_duplicate_evidence() -> None:
+    run_ref = _run_ref()
+    artifact = _artifact(run_ref)
+    with pytest.raises(BacktestContractError) as wrong_run:
+        build_backtest_evidence_manifest(
+            run_ref,
+            _artifact(run_ref, run_id="different-run"),
+            artifact_available_at="2026-01-08T02:05:00Z",
+        )
+    _assert_error(
+        wrong_run,
+        BacktestContractErrorCode.IDENTITY_MISMATCH,
+        "$.artifact.tables.run.run_id",
+    )
+    missing_signals = replace(artifact, _signals=None)  # type: ignore[arg-type]
+    with pytest.raises(BacktestContractError) as missing_table:
+        build_backtest_evidence_manifest(
+            run_ref,
+            missing_signals,
+            artifact_available_at="2026-01-08T02:05:00Z",
+        )
+    _assert_error(
+        missing_table,
+        BacktestContractErrorCode.TYPE_ERROR,
+        "$.artifact.tables.signals",
+    )
+    with pytest.raises(BacktestContractError) as digest_mismatch:
+        build_backtest_evidence_manifest(
+            run_ref,
+            artifact,
+            artifact_available_at="2026-01-08T02:05:00Z",
+            expected_table_digests={"performance": "sha256:" + "0" * 64},
+        )
+    _assert_error(
+        digest_mismatch,
+        BacktestContractErrorCode.EVIDENCE_MISMATCH,
+        "$.artifact.tables.performance.content_digest",
+    )
+    manifest = build_backtest_evidence_manifest(
+        run_ref,
+        artifact,
+        artifact_available_at="2026-01-08T02:05:00Z",
+    )
+    duplicate = manifest.to_dict()
+    duplicate["evidence"].append(copy.deepcopy(duplicate["evidence"][0]))
+    with pytest.raises(BacktestContractError) as duplicate_category:
+        BacktestEvidenceManifest.from_dict(
+            duplicate,
+            backtest_run_ref=run_ref,
+            artifact=artifact,
+        )
+    _assert_error(
+        duplicate_category,
+        BacktestContractErrorCode.INVALID_VALUE,
+        "$.evidence[8].category",
+    )
+
+
+def test_manifest_binds_supported_schema_and_has_collision_free_cell_encoding() -> None:
+    run_ref = _run_ref()
+    artifact = _artifact(run_ref)
+
+    with pytest.raises(BacktestContractError) as unsupported_schema:
+        build_backtest_evidence_manifest(
+            run_ref,
+            replace(artifact, schema_version="999.0.0"),
+            artifact_available_at="2026-01-08T02:05:00Z",
+        )
+    _assert_error(
+        unsupported_schema,
+        BacktestContractErrorCode.INVALID_VALUE,
+        "$.artifact.schema_version",
+    )
+
+    identities: set[str] = set()
+    for value in (float("nan"), float("inf"), float("-inf")):
+        performance = artifact.performance
+        performance.loc[0, "alpha"] = value
+        manifest = build_backtest_evidence_manifest(
+            run_ref,
+            replace(artifact, _performance=performance),
+            artifact_available_at="2026-01-08T02:05:00Z",
+        )
+        assert manifest.artifact_schema_version == RESEARCH_ARTIFACT_SCHEMA_VERSION
+        identities.add(manifest.manifest_id)
+    assert len(identities) == 3
+
+    content_digests: set[str] = set()
+    for value in (float("nan"), {"non_finite_float": "nan"}):
+        performance = artifact.performance.astype(object)
+        performance.at[0, "alpha"] = value
+        manifest = build_backtest_evidence_manifest(
+            run_ref,
+            replace(artifact, _performance=performance),
+            artifact_available_at="2026-01-08T02:05:00Z",
+        )
+        performance_entry = next(
+            entry for entry in manifest.evidence if entry.category == "performance"
+        )
+        content_digests.add(performance_entry.tables[0].content_digest)
+    assert len(content_digests) == 2
+
+    unsupported = artifact.performance.astype(object)
+    unsupported.loc[0, "alpha"] = object()
+    with pytest.raises(BacktestContractError) as unsupported_cell:
+        build_backtest_evidence_manifest(
+            run_ref,
+            replace(artifact, _performance=unsupported),
+            artifact_available_at="2026-01-08T02:05:00Z",
+        )
+    _assert_error(
+        unsupported_cell,
+        BacktestContractErrorCode.TYPE_ERROR,
+        "$.artifact.tables.performance.rows[0].alpha",
+    )
+
+    invalid_nested_key = artifact.performance.astype(object)
+    invalid_nested_key.at[0, "alpha"] = {"\ud800": "value"}
+    with pytest.raises(BacktestContractError) as invalid_utf8:
+        build_backtest_evidence_manifest(
+            run_ref,
+            replace(artifact, _performance=invalid_nested_key),
+            artifact_available_at="2026-01-08T02:05:00Z",
+        )
+    _assert_error(
+        invalid_utf8,
+        BacktestContractErrorCode.INVALID_FORMAT,
+        "$.artifact.tables.performance.rows[0].alpha.keys",
+    )
+
+    unsafe_integer = artifact.performance.astype(object)
+    unsafe_integer.loc[0, "alpha"] = 10**5000
+    with pytest.raises(BacktestContractError) as unsafe_cell:
+        build_backtest_evidence_manifest(
+            run_ref,
+            replace(artifact, _performance=unsafe_integer),
+            artifact_available_at="2026-01-08T02:05:00Z",
+        )
+    _assert_error(
+        unsafe_cell,
+        BacktestContractErrorCode.INVALID_VALUE,
+        "$.artifact.tables.performance.rows[0].alpha",
+    )
+
+
+def test_artifact_canonical_content_has_typed_collision_free_cell_encoding() -> None:
+    run_ref = _run_ref()
+    artifact = _artifact(run_ref)
+
+    content_hashes: set[str] = set()
+    for value in (
+        float("nan"),
+        float("inf"),
+        float("-inf"),
+        {"non_finite_float": "nan"},
+    ):
+        performance = artifact.performance.astype(object)
+        performance.at[0, "alpha"] = value
+        mutated = replace(artifact, _performance=performance)
+        content_hashes.add(mutated.content_sha256)
+        assert "non_finite_float" in mutated.canonical_json()
+    assert len(content_hashes) == 4
+
+    unsupported = artifact.performance.astype(object)
+    unsupported.loc[0, "alpha"] = object()
+    with pytest.raises(BacktestContractError) as unsupported_cell:
+        replace(artifact, _performance=unsupported).canonical_json()
+    _assert_error(
+        unsupported_cell,
+        BacktestContractErrorCode.TYPE_ERROR,
+        "$.tables.performance.rows[0].alpha",
+    )
+
+
+def test_legacy_bridge_is_explicit_and_cannot_be_contract_qualified() -> None:
+    run_ref = _run_ref()
+    legacy_run = BacktestRun(
+        run_id="legacy-run-001",
+        dataset_snapshot_id=run_ref.dataset_snapshot_id,
+        factor_version_id="alpha_005@1.0.0",
+        strategy_version_id="alpha-top1@1.0.0",
+        code_revision=run_ref.code_revision,
+        config_hash=_config_digest().removeprefix("sha256:"),
+        created_at=datetime(2026, 1, 8, 2, 0, tzinfo=UTC),
+    )
+    artifact = _artifact(run_ref, run_id=legacy_run.run_id)
+    manifest = build_legacy_backtest_evidence_manifest(
+        legacy_run,
+        artifact,
+        artifact_available_at="2026-01-08T02:05:00Z",
+    )
+
+    assert manifest.qualification is EvidenceQualification.LEGACY_EXPLORATORY
+    assert manifest.run_id == legacy_run.run_id
+    assert manifest.backtest_run_ref is None
+    assert manifest.to_dict()["run_reference"]["kind"] == "legacy_backtest_run"
+    assert BacktestEvidenceManifest.from_dict(
+        manifest.to_dict(),
+        artifact=artifact,
+    ) == manifest
+    with pytest.raises(BacktestContractError) as implicit_promotion:
+        build_backtest_evidence_manifest(  # type: ignore[arg-type]
+            legacy_run,
+            artifact,
+            artifact_available_at="2026-01-08T02:05:00Z",
+            qualification=EvidenceQualification.CONTRACT_QUALIFIED,
+        )
+    _assert_error(
+        implicit_promotion,
+        BacktestContractErrorCode.TYPE_ERROR,
+        "$.backtest_run_ref",
+    )
+
+
+def test_golden_contract_and_architecture_boundary() -> None:
+    run_ref = _run_ref()
+    artifact = _artifact(run_ref)
+    manifest = build_backtest_evidence_manifest(
+        run_ref,
+        artifact,
+        artifact_available_at="2026-01-08T02:05:00Z",
+    )
+    golden = json.loads(BACKTEST_FIXTURE.read_text(encoding="utf-8"))
+
+    table_digests = {
+        table.logical_name: table.content_digest
+        for item in manifest.evidence
+        for table in item.tables
+    }
+    assert golden == {
+        "run_id": run_ref.run_id,
+        "replay_spec_digest": run_ref.replay_spec_digest,
+        "manifest_id": manifest.manifest_id,
+        "evidence_digest": manifest.evidence_digest,
+        "table_content_digests": table_digests,
+    }
+    governed_source = (ROOT / "src" / "quant_engine" / "governed_pipeline.py").read_text(
+        encoding="utf-8"
+    )
+    artifact_source = (ROOT / "src" / "quant_engine" / "artifact.py").read_text(
+        encoding="utf-8"
+    )
+    assert "from quant_engine.artifact" not in governed_source
+    assert "BacktestRunRef" in governed_source
+    assert "BacktestEvidenceManifest" not in governed_source
+    assert "BacktestEvidenceManifest" in artifact_source
+    assert not (ROOT / "src" / "quant_engine" / "backtest_contracts.py").exists()