diff --git a/CHANGELOG.md b/CHANGELOG.md
index f747adeae..4844de44f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,7 @@ All notable changes to OriginWeave are documented in this file. The format follo
 
 ## [Unreleased]
 
+- Scoped pull-request workflow cancellation by workflow, repository, and PR while keeping push and manual runs independent; removed the completed nightly materializer and the redundant standalone `cargo check`, with all-target Clippy retained as the workspace compile/check gate.
 - Refreshed the product-gap queue to 126 open pull requests (54 ready, 72 draft) after #190, #188, #185, #192, #182, #184, #115, #181, #116, #117, #118, #183, #114, #127, #112, #109, #186, #110, #108, #111, #174, and #113 were merged into their immediate stacked prerequisites. PRs #147, #146, #145, #144, #143, #142, #141, #139, #136, #132, #129, and #128 moved to ready after exact-head checks and thread review; these are queue-consolidation results, not protected-main shipment.
 
 ### Added
@@ -102,4 +103,4 @@ All notable changes to OriginWeave are documented in this file. The format follo
 - The hourly product agent has no Git metadata or repository authority. A separate post-verification publisher opens one PR and cannot approve or merge it.
 - The unprivileged OpenCode user is restricted to loopback egress during model execution, preventing runner-wide allow-listed endpoints from becoming direct source-exfiltration channels.
 
-[Unreleased]: https://github.com/ContextualWisdomLab/OriginWeave/compare/main...HEAD
\ No newline at end of file
+[Unreleased]: https://github.com/ContextualWisdomLab/OriginWeave/compare/main...HEAD
diff --git a/docs/quality-gates.md b/docs/quality-gates.md
index b58f8902f..de72506b2 100644
--- a/docs/quality-gates.md
+++ b/docs/quality-gates.md
@@ -10,7 +10,7 @@ A PR is mergeable only when all apply:
 - required PR checks explicitly check out the pull request head SHA; GitHub synthetic merge-ref evidence is supplemental and cannot substitute for exact-head evidence;
 - production function, line, region, and branch coverage each at 100%;
 - all public Rust APIs documented and rustdoc warnings denied;
-- format, check, test, Clippy, and documentation jobs pass;
+- format, test, Clippy, and documentation jobs pass; Clippy is the workspace compile/check gate because CI lints every target, so a separate `cargo check` invocation is not required;
 - dependency and GitHub Action references are locked or commit-pinned;
 - generated build outputs are ignored and absent from `git ls-files`;
 - review threads are resolved with code or evidence;
diff --git a/tests/test_pr284_governance_contract.py b/tests/test_pr284_governance_contract.py
new file mode 100644
index 000000000..833e01e27
--- /dev/null
+++ b/tests/test_pr284_governance_contract.py
@@ -0,0 +1,47 @@
+"""Regression contracts for the PR #284/#286 CI-governance repairs."""
+
+from __future__ import annotations
+
+import pathlib
+import unittest
+
+ROOT = pathlib.Path(__file__).resolve().parents[1]
+
+
+class WorkflowGovernanceRepairTests(unittest.TestCase):
+    """Keep workflow optimization, lifecycle admission, and docs in one contract."""
+
+    def test_concurrency_and_draft_lifecycle_contracts_remain_composed(self) -> None:
+        """Main must retain both exact concurrency scoping and Draft-run admission rules."""
+
+        ci = (ROOT / ".github/workflows/ci.yml").read_text(encoding="utf-8")
+        mv3 = (ROOT / ".github/workflows/mv3-compatibility.yml").read_text(encoding="utf-8")
+        concurrency = (
+            "concurrency:\n"
+            "  group: ${{ github.workflow }}-${{ github.repository }}-"
+            "${{ github.event.pull_request.number || github.run_id }}\n"
+            "  cancel-in-progress: ${{ github.event_name == 'pull_request' }}"
+        )
+        lifecycle = (
+            "types: [opened, synchronize, reopened, ready_for_review, "
+            "converted_to_draft, closed]"
+        )
+
+        self.assertIn(concurrency, ci)
+        self.assertIn(concurrency, mv3)
+        self.assertIn(lifecycle, ci)
+        self.assertIn(lifecycle, mv3)
+        self.assertEqual(ci.count("github.event.pull_request.draft == false"), 2)
+        self.assertIn("github.event.pull_request.draft == false", mv3)
+
+    def test_quality_gate_and_changelog_describe_the_optimized_ci_boundary(self) -> None:
+        """Repository docs must retain the post-optimization compile/check semantics."""
+
+        quality_gates = (ROOT / "docs/quality-gates.md").read_text(encoding="utf-8")
+        changelog = (ROOT / "CHANGELOG.md").read_text(encoding="utf-8")
+        self.assertIn("Clippy is the workspace compile/check gate", quality_gates)
+        self.assertIn("Scoped pull-request workflow cancellation", changelog)
+
+
+if __name__ == "__main__":
+    unittest.main()