diff --git a/CHANGELOG.md b/CHANGELOG.md
index 66cb38557..100890984 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -279,6 +279,11 @@
 - Added sentinel delegation tests, Rust edge-case tests, seeded true-trait
   recovery tests, score-equation checks, and APA 7th CAT doctoring.
 
+#### Automatic backend preserves Rust numerical ownership
+
+- Changed `backend="auto"` so a missing compiled Rust core fails closed instead of silently selecting the independent NumPy reference implementation.
+- Kept explicit `backend="numpy"` as an explicit reference/parity choice while preserving automatic Rust resolution and Rust CPU/GPU device fallback semantics.
+
 #### Current support-policy version line
 
 - Aligned the public security and support policies with the released `0.7.x` pre-1.0 package line instead of the obsolete `0.1.x` policy.
@@ -312,6 +317,11 @@
 
 ### Fixed
 
+#### Serving bundle export requires Rust core
+
+- `export_serving_bundle` fails closed when the compiled Rust core is unavailable
+  instead of shipping incomplete bundles with null `eapsum_tables`.
+
 #### Fail early for unimplemented estimator identities
 
 - Restricted the public `FitConfig.estimator` vocabulary to the implemented `jmle` and `mmle` fitting paths, so unsupported `em` and `bayes` requests fail during configuration validation instead of entering a fitting path that later raises `NotImplementedError`.
@@ -331,6 +341,10 @@
 
 - Validate automated-test-assembly content-label shape and string element types before item-information evaluation, rejecting arbitrary object labels without invoking caller-controlled `__str__`/`__repr__` callbacks while preserving accepted Python/NumPy string labels and existing assembly numerics.
 
+#### Bound PR queue Git metadata lookup
+
+- PR queue governance now bounds the `git rev-parse HEAD` subprocess and fails closed with a stable timeout error instead of allowing a hung local Git child to stall the evidence pipeline.
+
 #### Diagnostics-report focus and contrast preservation
 
 - Revealed the visually hidden diagnostics-report skip link for every actual `:focus` state while retaining the explicit `:focus-visible` treatment and strong outline.
@@ -343,6 +357,10 @@
 
 - Stopped reflecting caller-controlled invalid response values in `person_fit_np()` validation errors while preserving the failing matrix coordinate and the complete-data 0/1 response contract.
 
+#### Bounded mixed item-model validation
+
+- Bounded `item_models` iterable consumption to at most one look-ahead entry beyond the calibrated item count, rejected arbitrary non-string model controls before caller `__str__`/`__repr__` hooks can execute, and removed rejected model content from public validation errors while preserving accepted aliases and Rust-owned calibration numerics.
+
 #### Model-comparison control validation hardening
 
 - Reject hostile semantic/numeric control objects before caller-defined `__str__`, `__repr__`, or `__float__` callbacks can execute, while preserving accepted relation identities, built-in/NumPy scalar semantics, and Rust-owned model-comparison arithmetic.
diff --git a/docs/changelog.d/707-pr-queue-git-metadata-timeout.md b/docs/changelog.d/707-pr-queue-git-metadata-timeout.md
new file mode 100644
index 000000000..4bc55f278
--- /dev/null
+++ b/docs/changelog.d/707-pr-queue-git-metadata-timeout.md
@@ -0,0 +1,5 @@
+# Bound PR queue Git metadata lookup
+
+## Fixed
+
+- PR queue governance now bounds the `git rev-parse HEAD` subprocess and fails closed with a stable timeout error instead of allowing a hung local Git child to stall the evidence pipeline.
diff --git a/scripts/build_pr_queue_governance.py b/scripts/build_pr_queue_governance.py
index 7c6234b20..65b8b3b9e 100644
--- a/scripts/build_pr_queue_governance.py
+++ b/scripts/build_pr_queue_governance.py
@@ -86,6 +86,7 @@
 _GH_TRANSIENT_STATUS_RE = re.compile(r"\bHTTP (?:502|503|504)\b", re.IGNORECASE)
 _GH_JSON_MAX_ATTEMPTS = 3
 _GH_JSON_RETRY_SLEEP_SECONDS = 0.5
+GIT_METADATA_TIMEOUT_SECONDS = 5
 
 
 def _parse_datetime(value: str) -> datetime:
@@ -122,7 +123,7 @@ def _resolve_path(value: str | Path, *, base: Path) -> Path:
 
 
 def _source_commit(repo_root: Path) -> str:
-    """Return the checked-out commit SHA, or ``unknown`` when unavailable."""
+    """Return the checked-out commit SHA, failing closed on a hung Git child."""
     try:
         completed = subprocess.run(
             ["git", "rev-parse", "HEAD"],
@@ -130,7 +131,10 @@ def _source_commit(repo_root: Path) -> str:
             capture_output=True,
             text=True,
             check=True,
+            timeout=GIT_METADATA_TIMEOUT_SECONDS,
         )
+    except subprocess.TimeoutExpired as exc:
+        raise RuntimeError("source commit lookup timed out") from exc
     except Exception:
         return "unknown"
     return completed.stdout.strip() or "unknown"
diff --git a/tests/test_pr_queue_governance_git_timeout.py b/tests/test_pr_queue_governance_git_timeout.py
new file mode 100644
index 000000000..c3dffb259
--- /dev/null
+++ b/tests/test_pr_queue_governance_git_timeout.py
@@ -0,0 +1,40 @@
+"""Fail-first reliability contracts for PR queue governance Git metadata reads."""
+
+from __future__ import annotations
+
+import importlib.util
+import subprocess
+from pathlib import Path
+
+import pytest
+
+
+def _load_governance():
+    """Load the PR queue governance script as a module for boundary tests."""
+    script = Path(__file__).resolve().parents[1] / "scripts" / "build_pr_queue_governance.py"
+    spec = importlib.util.spec_from_file_location("build_pr_queue_governance", script)
+    assert spec is not None
+    module = importlib.util.module_from_spec(spec)
+    assert spec.loader is not None
+    spec.loader.exec_module(module)
+    return module
+
+
+def test_source_commit_bounds_git_metadata_lookup(monkeypatch, tmp_path: Path) -> None:
+    """A hung ``git rev-parse`` must fail closed under a package-owned deadline."""
+    module = _load_governance()
+    observed_timeouts: list[object] = []
+
+    def timeout_run(*args, **kwargs):
+        observed_timeouts.append(kwargs.get("timeout"))
+        raise subprocess.TimeoutExpired(
+            cmd=args[0] if args else kwargs.get("args", ["git", "rev-parse", "HEAD"]),
+            timeout=kwargs.get("timeout"),
+        )
+
+    monkeypatch.setattr(module.subprocess, "run", timeout_run)
+
+    with pytest.raises(RuntimeError, match="source commit lookup timed out"):
+        module._source_commit(tmp_path)
+
+    assert observed_timeouts == [module.GIT_METADATA_TIMEOUT_SECONDS]