docs: add Signed commits section to CONTRIBUTING

[hyperpolymath]

Adds a Signed commits section to this repo's CONTRIBUTING, per owner ruling D218. The estate policy is docs/SIGNING-POLICY.adoc in hyperpolymath/standards.

This repo's default branch is covered by the zero-bypass Require-Signed-Commits ruleset, and rebase-merge is off. The section tells contributors what that requires:

• People and interactive agents sign with an SSH signing key.
• Apps, bots and workflows write through the API, so GitHub signs their commits.
• PRs are merged with squash.

If the file already had its own signing section, that section is replaced in place instead of adding a second one. Lines elsewhere that told people to sign with GPG are changed to match the policy (SSH for people).

This is a docs-only change. The commit was created through createCommitOnBranch, so GitHub signs it.

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ℹ️ Recent review info

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Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Advanced

Run ID: b4da849a-c582-4d92-85ed-74aaeaffbd5c

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📜 Recent review details

⏰ Context from checks skipped due to timeout. (21)

• GitHub Check: copilot-pull-request-reviewer
• GitHub Check: github-advanced-security
• GitHub Check: scan / shell-secrets
• GitHub Check: scan / gitleaks
• GitHub Check: governance / Check Workflow Staleness
• GitHub Check: governance / Trusted-base reduction policy
• GitHub Check: governance / Workflow security linter
• GitHub Check: governance / Exemption ratchet
• GitHub Check: governance / Guix packaging policy (Nix retired)
• GitHub Check: governance / Debt ratchet
• GitHub Check: governance / Licence consistency
• GitHub Check: governance / Live Actions policy (credentialed advisory)
• GitHub Check: governance / Code quality + docs
• GitHub Check: governance / Language / package anti-pattern policy
• GitHub Check: governance / Security policy checks
• GitHub Check: governance / Actions lockfile verify
• GitHub Check: governance / Allowlist Preflight
• GitHub Check: hypatia / Hypatia Neurosymbolic Analysis
• GitHub Check: Check License Compliance
• GitHub Check: Review Dependencies
• GitHub Check: semgrep-cloud-platform/scan

⚠️ CI failures not shown inline (15)

GitHub Actions: Governance / 3_governance _ Workflow security linter.txt: docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run if [ "$GITHUB_REPOSITORY" = hyperpolymath/standards ]; then
 �[36;1mif [ "$GITHUB_REPOSITORY" = hyperpolymath/standards ]; then�[0m
 �[36;1m  SCRIPT=scripts/check-descriptile-policy.sh�[0m
 �[36;1melse�[0m
 �[36;1m  SCRIPT=.standards-dupkey/scripts/check-descriptile-policy.sh�[0m
 �[36;1mfi�[0m
 �[36;1mbash "$SCRIPT"�[0m
 shell: /usr/bin/bash -e {0}
 ##[endgroup]
 55:    @[ -f ".machine_readable/STATE.a2ml" ] && grep -oP 'phase\s*=\s*"\K[^"]+' .machine_readable/STATE.a2ml | head -1 | xargs -I{} echo "Phase: {}" || true
 552:    @if [ -f ".machine_readable/STATE.a2ml" ]; then \
 ##[error]Policy requires a retired descriptile path; use .machine_readable/descriptiles/ and reconcile existing files

---

GitHub Actions: Governance / governance _ Workflow security linter: docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run if [ "$GITHUB_REPOSITORY" = hyperpolymath/standards ]; then
 �[36;1mif [ "$GITHUB_REPOSITORY" = hyperpolymath/standards ]; then�[0m
 �[36;1m  SCRIPT=scripts/check-descriptile-policy.sh�[0m
 �[36;1melse�[0m
 �[36;1m  SCRIPT=.standards-dupkey/scripts/check-descriptile-policy.sh�[0m
 �[36;1mfi�[0m
 �[36;1mbash "$SCRIPT"�[0m
 shell: /usr/bin/bash -e {0}
 ##[endgroup]
 55:    @[ -f ".machine_readable/STATE.a2ml" ] && grep -oP 'phase\s*=\s*"\K[^"]+' .machine_readable/STATE.a2ml | head -1 | xargs -I{} echo "Phase: {}" || true
 552:    @if [ -f ".machine_readable/STATE.a2ml" ]; then \
 ##[error]Policy requires a retired descriptile path; use .machine_readable/descriptiles/ and reconcile existing files

---

GitHub Actions: Governance / 4_governance _ Guix packaging policy (Nix retired).txt: docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run # Move the checker OUT of the scanned tree and delete the standards
 �[36;1m# Move the checker OUT of the scanned tree and delete the standards�[0m
 �[36;1m# checkout before scanning: the gate walks the whole caller tree, so�[0m
 �[36;1m# a packaging file shipped inside .standards-checkout/ would satisfy�[0m
 �[36;1m# the policy on the caller's behalf (same trap as the baseline job).�[0m
 �[36;1mcp .standards-checkout/scripts/check-package-policy.sh "$RUNNER_TEMP/"�[0m
 �[36;1mrm -rf .standards-checkout�[0m
 �[36;1mbash "$RUNNER_TEMP/check-package-policy.sh" .�[0m
 shell: /usr/bin/bash -e {0}
 ##[endgroup]
 ##[error]Package policy violation: no packaging found.

---

GitHub Actions: Governance / governance _ Guix packaging policy (Nix retired): docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run # Move the checker OUT of the scanned tree and delete the standards
 �[36;1m# Move the checker OUT of the scanned tree and delete the standards�[0m
 �[36;1m# checkout before scanning: the gate walks the whole caller tree, so�[0m
 �[36;1m# a packaging file shipped inside .standards-checkout/ would satisfy�[0m
 �[36;1m# the policy on the caller's behalf (same trap as the baseline job).�[0m
 �[36;1mcp .standards-checkout/scripts/check-package-policy.sh "$RUNNER_TEMP/"�[0m
 �[36;1mrm -rf .standards-checkout�[0m
 �[36;1mbash "$RUNNER_TEMP/check-package-policy.sh" .�[0m
 shell: /usr/bin/bash -e {0}
 ##[endgroup]
 ##[error]Package policy violation: no packaging found.

---

GitHub Actions: Governance / 6_governance _ Language _ package anti-pattern policy.txt: docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run SCRIPT=".standards-checkout/scripts/check-ts-allowlist.sh"
 �[36;1mSCRIPT=".standards-checkout/scripts/check-ts-allowlist.sh"�[0m
 �[36;1mif [ ! -f "$SCRIPT" ] && [ "$GITHUB_REPOSITORY" = "hyperpolymath/standards" ] \�[0m
 �[36;1m   && [ -f scripts/check-ts-allowlist.sh ]; then�[0m
 �[36;1m  SCRIPT="scripts/check-ts-allowlist.sh"�[0m
 �[36;1m  echo "Using this repository's own copy (standards self-check)."�[0m
 �[36;1mfi�[0m
 �[36;1mif [ ! -f "$SCRIPT" ]; then�[0m
 �[36;1m  echo "::error::check-ts-allowlist gate not found in standards@main or locally"�[0m

---

GitHub Actions: Governance / governance _ Language _ package anti-pattern policy: docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run SCRIPT=".standards-checkout/scripts/check-ts-allowlist.sh"
 �[36;1mSCRIPT=".standards-checkout/scripts/check-ts-allowlist.sh"�[0m
 �[36;1mif [ ! -f "$SCRIPT" ] && [ "$GITHUB_REPOSITORY" = "hyperpolymath/standards" ] \�[0m
 �[36;1m   && [ -f scripts/check-ts-allowlist.sh ]; then�[0m
 �[36;1m  SCRIPT="scripts/check-ts-allowlist.sh"�[0m
 �[36;1m  echo "Using this repository's own copy (standards self-check)."�[0m
 �[36;1mfi�[0m
 �[36;1mif [ ! -f "$SCRIPT" ]; then�[0m
 �[36;1m  echo "::error::check-ts-allowlist gate not found in standards@main or locally"�[0m

---

GitHub Actions: Governance / governance _ Language _ package anti-pattern policy: docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run SCRIPT=".standards-checkout/tools/policy/check-language-policy.sh"
 �[36;1mSCRIPT=".standards-checkout/tools/policy/check-language-policy.sh"�[0m
 �[36;1mif [ ! -f "$SCRIPT" ] && [ -f tools/policy/check-language-policy.sh ]; then�[0m
 �[36;1m  SCRIPT="tools/policy/check-language-policy.sh"�[0m
 �[36;1m  echo "Using this repository's own copy (standards self-check)."�[0m
 �[36;1mfi�[0m
 �[36;1mif [ ! -f "$SCRIPT" ]; then�[0m
 �[36;1m  echo "::error::language-policy gate not found in standards@main or locally"�[0m

---

GitHub Actions: Governance / 7_governance _ Well-Known (RFC 9116 + RSR).txt: docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run SECTXT=""
 �[36;1mSECTXT=""�[0m
 �[36;1m[ -f ".well-known/security.txt" ] && SECTXT=".well-known/security.txt"�[0m
 �[36;1m[ -f "security.txt" ] && SECTXT="security.txt"�[0m
 �[36;1mif [ -z "$SECTXT" ]; then�[0m
 �[36;1m  echo "::warning::No security.txt found."�[0m
 �[36;1m  exit 0�[0m
 �[36;1mfi�[0m
 �[36;1mgrep -q "^Contact:" "$SECTXT" || { echo "::error::Missing Contact field"; exit 1; }�[0m

---

GitHub Actions: Governance / governance _ Well-Known (RFC 9116 + RSR): docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run SECTXT=""
 �[36;1mSECTXT=""�[0m
 �[36;1m[ -f ".well-known/security.txt" ] && SECTXT=".well-known/security.txt"�[0m
 �[36;1m[ -f "security.txt" ] && SECTXT="security.txt"�[0m
 �[36;1mif [ -z "$SECTXT" ]; then�[0m
 �[36;1m  echo "::warning::No security.txt found."�[0m
 �[36;1m  exit 0�[0m
 �[36;1mfi�[0m
 �[36;1mgrep -q "^Contact:" "$SECTXT" || { echo "::error::Missing Contact field"; exit 1; }�[0m

---

GitHub Actions: Governance / governance _ Well-Known (RFC 9116 + RSR): docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run MIXED=$(grep -rE 'src="http://|href="http://' --include="*.html" --include="*.htm" . 2>/dev/null | grep -vE 'localhost|127\.0\.0\.1|example\.com|lol/|node_modules/|third-party/|vendor/' | head -5 || true)
 �[36;1mMIXED=$(grep -rE 'src="http://|href="http://' --include="*.html" --include="*.htm" . 2>/dev/null | grep -vE 'localhost|127\.0\.0\.1|example\.com|lol/|node_modules/|third-party/|vendor/' | head -5 || true)�[0m
 �[36;1mif [ -n "$MIXED" ]; then�[0m
 �[36;1m  echo "::error::Mixed content (HTTP in HTML)"�[0m

---

GitHub Actions: Governance / 13_governance _ Security policy checks.txt: docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run FAILED=false
 �[36;1mFAILED=false�[0m
 �[36;1mWEAK_CRYPTO=$(grep -rE 'md5\(|sha1\(' --include="*.py" --include="*.rb" --include="*.js" --include="*.ts" --include="*.go" --include="*.rs" . 2>/dev/null | grep -v 'checksum\|cache\|test\|spec' | head -5 || true)�[0m
 �[36;1mif [ -n "$WEAK_CRYPTO" ]; then�[0m
 �[36;1m  echo "::warning::Weak crypto (MD5/SHA1) detected — ADVISORY, does not fail this job. Use SHA256+:"�[0m
 �[36;1m  echo "$WEAK_CRYPTO"�[0m
 �[36;1mfi�[0m
 �[36;1mHTTP_URLS=$(grep -rE 'http://[^l][^o][^c]' --include="*.py" --include="*.js" --include="*.ts" --include="*.go" --include="*.rs" --include="*.yaml" --include="*.yml" . 2>/dev/null | grep -v 'localhost\|127.0.0.1\|example\|test\|spec' | head -5 || true)�[0m
 �[36;1mif [ -n "$HTTP_URLS" ]; then�[0m
 �[36;1m  echo "::warning::HTTP URLs found — ADVISORY, does not fail this job. Use HTTPS:"�[0m
 �[36;1m  echo "$HTTP_URLS"�[0m
 �[36;1mfi�[0m
 �[36;1mSECRETS=$(grep -rEi '(api_key|apikey|secret_key|password)\s*[=:]\s*["\x27][A-Za-z0-9+/=]{20,}' --include="*.py" --include="*.js" --include="*.ts" --include="*.go" --include="*.rs" --include="*.env" . 2>/dev/null | grep -v 'example\|sample\|test\|mock\|placeholder' | head -3 || true)�[0m
 �[36;1mif [ -n "$SECRETS" ]; then�[0m
 �[36;1m  echo "::error::Potential hardcoded secrets detected — this FAILS the job:"�[0m

---

GitHub Actions: Governance / governance _ Security policy checks: docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run FAILED=false
 �[36;1mFAILED=false�[0m
 �[36;1mWEAK_CRYPTO=$(grep -rE 'md5\(|sha1\(' --include="*.py" --include="*.rb" --include="*.js" --include="*.ts" --include="*.go" --include="*.rs" . 2>/dev/null | grep -v 'checksum\|cache\|test\|spec' | head -5 || true)�[0m
 �[36;1mif [ -n "$WEAK_CRYPTO" ]; then�[0m
 �[36;1m  echo "::warning::Weak crypto (MD5/SHA1) detected — ADVISORY, does not fail this job. Use SHA256+:"�[0m
 �[36;1m  echo "$WEAK_CRYPTO"�[0m
 �[36;1mfi�[0m
 �[36;1mHTTP_URLS=$(grep -rE 'http://[^l][^o][^c]' --include="*.py" --include="*.js" --include="*.ts" --include="*.go" --include="*.rs" --include="*.yaml" --include="*.yml" . 2>/dev/null | grep -v 'localhost\|127.0.0.1\|example\|test\|spec' | head -5 || true)�[0m
 �[36;1mif [ -n "$HTTP_URLS" ]; then�[0m
 �[36;1m  echo "::warning::HTTP URLs found — ADVISORY, does not fail this job. Use HTTPS:"�[0m
 �[36;1m  echo "$HTTP_URLS"�[0m
 �[36;1mfi�[0m
 �[36;1mSECRETS=$(grep -rEi '(api_key|apikey|secret_key|password)\s*[=:]\s*["\x27][A-Za-z0-9+/=]{20,}' --include="*.py" --include="*.js" --include="*.ts" --include="*.go" --include="*.rs" --include="*.env" . 2>/dev/null | grep -v 'example\|sample\|test\|mock\|placeholder' | head -3 || true)�[0m
 �[36;1mif [ -n "$SECRETS" ]; then�[0m
 �[36;1m  echo "::error::Potential hardcoded secrets detected — this FAILS the job:"�[0m

---

GitHub Actions: Governance / governance _ Security policy checks: docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run set -uo pipefail
 �[36;1mset -uo pipefail�[0m
 �[36;1mDIR=.github/canonical-references�[0m
 �[36;1mif [ ! -d "$DIR" ]; then�[0m
 �[36;1m  echo "ℹ️  [R5] no $DIR/ — skipped (repo has not opted in)"�[0m
 �[36;1m  exit 0�[0m
 �[36;1mfi�[0m
 �[36;1mif ! command -v python3 >/dev/null 2>&1; then�[0m
 �[36;1m  echo "❌ [R5] python3 missing on runner — required for YAML rule parsing"�[0m
 �[36;1m  exit 2�[0m
 �[36;1mfi�[0m
 �[36;1mpython3 - <<'PY'�[0m
 �[36;1mimport os, sys, glob, subprocess�[0m
 �[36;1mtry:�[0m
 �[36;1m    import yaml�[0m
 �[36;1mexcept ImportError:�[0m
 �[36;1m    sys.exit("❌ [R5] PyYAML not installed on runner; install python3-yaml")�[0m
 �[36;1m�[0m
 �[36;1mdir_ = ".github/canonical-references"�[0m
 �[36;1mfiles = sorted(glob.glob(f"{dir_}/*.yml") + glob.glob(f"{dir_}/*.yaml"))�[0m
 �[36;1mif not files:�[0m
 �[36;1m    print(f"ℹ️  [R5] {dir_}/ has no .yml/.yaml rules — skipped")�[0m
 �[36;1m    sys.exit(0)�[0m
 �[36;1m�[0m
 �[36;1mtotal = 0�[0m
 �[36;1mfor rf in files:�[0m
 �[36;1m    with open(rf, encoding="utf-8") as fh:�[0m
 �[36;1m        cfg = yaml.safe_load(fh)�[0m
 �[36;1m    if not isinstance(cfg, dict):�[0m
 �[36;1m        print(f"❌ [R5] {rf}: top-level must be a mapping"); total += 1; continue�[0m
 �[36;1m    rid  = cfg.get("id", os.path.basename(rf))�[0m
 �[36;1m    desc = cfg.get("description", "")�[0m
 �[36;1m    pats = cfg.get("patterns") or []�[0m
 �[36;1m    canon = cfg.get("canonical_pointer", "")�[0m
 �[36;1m    scope = (cfg.get("scope") or {})�[0m
 �[36;1m    includes = scope.get("include") or []�[0m
 �[36;1m    if not pats or not includes:�[0m
 �[36;1m        print(f"❌ [R5:{rid}] missing patterns or scope.include in {rf}")�[0m
 �[36;1m        total += 1; continue�[0m
 �[36;1m    # exclude self-references�[0m
 �[36;1m    skip = set(["CHANGELOG.md", "CHANGELOG.adoc", rf])�[0m
 �[36;1m    if canon: skip.add(canon)�[0m
 �[36;1m    rule_hits = 0�[0m
 �[36;1m    for f_ in includes:�[0m
 �[36;1m        if f_ in skip or not os...

---

GitHub Actions: Governance / 14_governance _ Actions lockfile verify.txt: docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run set -uo pipefail
 �[36;1mset -uo pipefail�[0m
 �[36;1mif [ "$GITHUB_REPOSITORY" = hyperpolymath/standards ]; then�[0m
 �[36;1m  SRC=scripts�[0m
 �[36;1m  echo "Using this repository's own gate + verifier (standards self-lint)."�[0m
 �[36;1melse�[0m
 �[36;1m  SRC=.standards-lock/scripts�[0m
 �[36;1mfi�[0m
 �[36;1mfor f in check-actions-lock-gate.sh update-actions-lock.sh; do�[0m
 �[36;1m  if [ ! -f "$SRC/$f" ]; then�[0m
 �[36;1m    echo "::error::actions-lock gate: $f not found in $SRC (standards checkout at the explicit helper pin failed?)"�[0m

---

GitHub Actions: Governance / governance _ Actions lockfile verify: docs: add Signed commits section to CONTRIBUTING

Conclusion: failure

View job details

##[group]Run set -uo pipefail
 �[36;1mset -uo pipefail�[0m
 �[36;1mif [ "$GITHUB_REPOSITORY" = hyperpolymath/standards ]; then�[0m
 �[36;1m  SRC=scripts�[0m
 �[36;1m  echo "Using this repository's own gate + verifier (standards self-lint)."�[0m
 �[36;1melse�[0m
 �[36;1m  SRC=.standards-lock/scripts�[0m
 �[36;1mfi�[0m
 �[36;1mfor f in check-actions-lock-gate.sh update-actions-lock.sh; do�[0m
 �[36;1m  if [ ! -f "$SRC/$f" ]; then�[0m
 �[36;1m    echo "::error::actions-lock gate: $f not found in $SRC (standards checkout at the explicit helper pin failed?)"�[0m

🔇 Additional comments (1)

.github/CONTRIBUTING.md (1)

123-138: LGTM!

---

📝 Summary

Summary by CodeRabbit

• Documentation
  • Added guidance on signing commits before they reach the default branch, including requirements for people, agents, apps and workflows.
  • Clarified that pull requests must use squash merges and that unsigned commits need to be recreated as signed commits.

Walkthrough

The contribution guide now documents commit-signing requirements, signing methods for different contributors, and merge requirements for pull requests.

Changes

Signed commit guidance

Layer / File(s)	Summary
Signing and merge requirements .github/CONTRIBUTING.md	The guide specifies signing methods for people, interactive agents, apps, bots, and workflows. It also documents squash merges, unsigned commits, and the disabled rebase-merge option.

Priority: ⬇️ Low

Estimated code review effort: 1 (Trivial) | ~5 minutes

Change: Other

Merge Risk: ⚪ Minimal · up to 891a5

The guide documents signing workflows and squash merging. Whether rebase merging is also allowed could not be confirmed, so no actionable merge blocker is established.

Architecture Summary

Architecture risk: 🔵 Low · up to 891a5

The changed surface does not map to a changed system, dependency edge, entrypoint, or external dependency.

Changed systems: None identified.

Architecture concerns
No architecture-level concerns identified.

Review details

Before / after behavior

• observed — Modified behavior in .github/CONTRIBUTING.md: Added guidance requiring signed commits on the default branch, specifying SSH signing and verified committer email for people and interactive agents, API-based signed commits for apps, bots, and workflows, and squash merges. The section states that unsigned commits block PR merges, recommends recreating affected branches with signed cherry-picks, and says rebase-merge is disabled.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely describes the documentation change: adding a Signed commits section to CONTRIBUTING.
Description check	✅ Passed	The description directly explains the Signed commits documentation change, its policy basis, and the signing requirements for contributors and automated systems.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 0…
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches 💡 1

🛠️ Fix failing CI checks 💡

• Commit to this branch
• Create a new PR

• Autopilot · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

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_{A rabbit signs each commit with care,
SSH keys make the mark clear.
Squash the branches, keep checks in sight,
Cherry-pick signed commits right.
The guide now tells the path to take.}

_{Comment @coderabbitai help to get the list of available commands.}

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[Copilot]

Copilot review overview

🟢 Approved

The documentation accurately reflects the linked signing policy and GitHub ruleset behavior.

Review effort: Balanced
Findings: None

What changed in this PR

Adds repository-specific signed-commit guidance aligned with estate policy.

Changes:

• Documents SSH signing for people and interactive agents.
• Defines API-based signing for automation and squash-only merging.

File	Description
.github/​CONTRIBUTING.md	Adds signed-commit requirements and remediation guidance.

---

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