diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index 4d9ae2f..7f8e2c2 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -15,6 +15,14 @@ updates:
           - "*"
 
   # Rust/Cargo
+    ignore:
+      # HOLD: github/codeql-action at v4.38.0 (SHA-pinned). v4.38.1 fails
+      # GitHub workflow-startup validation estate-wide (nexia-list#100;
+      # SHA-form re-bump bypassed versions-scoped ignores - see
+      # nexia-list#101/#104). Hold until upstream clears 4.38.1 or a
+      # newer release verifies green; revisit deliberately.
+      - dependency-name: "github/codeql-action"
+
   - package-ecosystem: "cargo"
     directory: "/"
     schedule:
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index 9aff062..08c1014 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -34,11 +34,11 @@ jobs:
       - name: Checkout
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@1c5b675653bb5c22dbe9b12b556ec555138e09fd # v3
+        uses: github/codeql-action/init@b96794f015dfd88f77b49b1c93e0fa7110f94c63 # v4.38.0 (4.38.1 blocked estate-wide; nexia-list#100)
         with:
           languages: ${{ matrix.language }}
           build-mode: ${{ matrix.build-mode }}
       - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@1c5b675653bb5c22dbe9b12b556ec555138e09fd # v3
+        uses: github/codeql-action/analyze@b96794f015dfd88f77b49b1c93e0fa7110f94c63 # v4.38.0 (4.38.1 blocked estate-wide; nexia-list#100)
         with:
           category: "/language:${{ matrix.language }}"
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 0000000..3bb4b6d
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,7 @@
+<!-- SPDX-License-Identifier: CC-BY-SA-4.0 -->
+<!-- Copyright (c) 2026 Jonathan D.A. Jewell (hyperpolymath) <j.d.a.jewell@open.ac.uk> -->
+
+# Contributing
+
+The contribution guide is maintained at
+[`.github/CONTRIBUTING.md`](.github/CONTRIBUTING.md).
diff --git a/audits/assail-classifications.a2ml b/audits/assail-classifications.a2ml
index 3e07cdb..3936161 100644
--- a/audits/assail-classifications.a2ml
+++ b/audits/assail-classifications.a2ml
@@ -1,4 +1,12 @@
 %A2ML
+;; SPDX-License-Identifier: MPL-2.0
+;; Copyright (c) 2026 Jonathan D.A. Jewell (hyperpolymath) <j.d.a.jewell@open.ac.uk>
+
+(metadata
+  (name "assail-classifications")
+  (version "1.0.0")
+)
+
 - suppression:
     file: 'src/init.rs'
     rule: 'UnboundedAllocation'