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**Table of Contents**

- [Week 2 Architecture Design 4: CI/CD Integration Gates](#week-2-architecture-design-4-cicd-integration-gates)
  - [Executive Summary](#executive-summary)
  - [Current State Analysis](#current-state-analysis)
    - [Existing CI Pipeline](#existing-ci-pipeline)
    - [Current Makefile.toml Tasks](#current-makefiletoml-tasks)
  - [Proposed Architecture](#proposed-architecture)
    - [1. Andon Signal Detection Gate](#1-andon-signal-detection-gate)
    - [2. Performance Regression Gate](#2-performance-regression-gate)
    - [3. GitHub Actions Integration](#3-github-actions-integration)
    - [4. Pre-Commit Git Hook](#4-pre-commit-git-hook)
  - [Rollback Strategy](#rollback-strategy)
    - [Gate Failure Scenarios](#gate-failure-scenarios)
  - [Success Criteria](#success-criteria)
    - [Functional Requirements](#functional-requirements)
    - [Non-Functional Requirements](#non-functional-requirements)
    - [Quality Gates](#quality-gates)
  - [Benefits Analysis](#benefits-analysis)
    - [Defect Prevention](#defect-prevention)
    - [Time Savings](#time-savings)
  - [Effort Estimates](#effort-estimates)
  - [ADR: CI/CD Integration Gates](#adr-cicd-integration-gates)

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# Week 2 Architecture Design 4: CI/CD Integration Gates

**Design Phase:** Reduce Waste - Automated Quality Validation
**Priority:** HIGH (prevents defects from reaching production)
**Effort Estimate:** 3 hours design + 5 hours implementation
**Target SLO:** <5 minutes gate execution, 100% pre-merge validation

---

## Executive Summary

**Problem:** No automated validation gates. Current: Manual checks, defects slip through.

**Solution:** CI/CD integration gates in Makefile.toml + GitHub Actions that block merges on:
- Compilation errors
- Test failures
- Breaking API changes
- Security vulnerabilities

**Benefits:**
- ✅ 100% automated pre-merge validation
- ✅ Zero defects from compilation/test errors
- ✅ Fast feedback (<5min for critical gates)
- ✅ Rollback strategy for gate failures

---

## Current State Analysis

### Existing CI Pipeline

**File:** `.github/workflows/ci.yml`

```yaml
jobs:
  file-organization:  # Runs but doesn't block on errors
  comprehensive-test:  # Runs but slow (30min timeout)
  build-matrix:  # Parallel builds across OS/Rust versions
  fmt:  # Checks formatting
  clippy:  # Linting
  coverage:  # Code coverage (informational only)
```

**Problems:**
1. **No gate enforcement** - Jobs can fail without blocking merge
2. **No Andon signal detection** - Doesn't parse compilation errors
3. **No performance SLO validation** - Doesn't check build/test times
4. **No breaking change detection** - Missing semver-checks integration

### Current Makefile.toml Tasks

**Existing:**
```toml
[tasks.check]  # Quick compilation check (5s timeout)
[tasks.lint]   # Clippy linting (adaptive timeout)
[tasks.test]   # All tests (30s timeout)
[tasks.pre-commit]  # Format + lint + test
[tasks.ci]  # Full CI pipeline
```

**Missing:**
- Andon signal parsing (extract error counts)
- Breaking change detection (semver-checks)
- Performance regression detection
- Git hook integration with timeout enforcement

---

## Proposed Architecture

### 1. Andon Signal Detection Gate

**Purpose:** Stop the line when compilation/test errors detected

**Implementation:**

```toml
# Makefile.toml

[tasks.andon-check]
description = "Detect Andon signals (compilation errors, test failures)"
workspace = false
script_runner = "@shell"
script = '''
#!/bin/bash
set -e

echo "🚨 ANDON SIGNAL CHECK - Detecting compilation errors and test failures..."
echo ""

# Initialize counters
COMPILE_ERRORS=0
TEST_FAILURES=0
CLIPPY_WARNINGS=0

# Run compilation check and capture errors
echo "📋 Running compilation check..."
if ! COMPILE_OUTPUT=$(cargo make check 2>&1); then
  # Count compilation errors
  COMPILE_ERRORS=$(echo "$COMPILE_OUTPUT" | grep -c "^error\[E[0-9]\+\]:" || echo "0")

  echo "❌ ANDON SIGNAL DETECTED: Compilation errors found"
  echo "   Error count: $COMPILE_ERRORS"
  echo ""
  echo "STOP THE LINE - Fix compilation errors before proceeding"
  echo ""
  echo "$COMPILE_OUTPUT" | grep -A 5 "^error\[E"
  exit 1
fi
echo "✅ No compilation errors"

# Run tests and capture failures
echo ""
echo "📋 Running tests..."
if ! TEST_OUTPUT=$(cargo make test 2>&1); then
  # Count test failures
  TEST_FAILURES=$(echo "$TEST_OUTPUT" | grep -c "test .* FAILED" || echo "0")

  echo "❌ ANDON SIGNAL DETECTED: Test failures found"
  echo "   Failure count: $TEST_FAILURES"
  echo ""
  echo "STOP THE LINE - Fix failing tests before proceeding"
  echo ""
  echo "$TEST_OUTPUT" | grep "test .* FAILED" -A 10
  exit 1
fi
echo "✅ All tests pass"

# Run clippy and capture warnings
echo ""
echo "📋 Running linting..."
if ! CLIPPY_OUTPUT=$(cargo make lint 2>&1); then
  # Count clippy warnings/errors
  CLIPPY_WARNINGS=$(echo "$CLIPPY_OUTPUT" | grep -c "warning:" || echo "0")

  echo "⚠️  ANDON SIGNAL DETECTED: Clippy warnings found"
  echo "   Warning count: $CLIPPY_WARNINGS"
  echo ""
  echo "INVESTIGATE - Review linting warnings"
  echo ""
  echo "$CLIPPY_OUTPUT" | grep "warning:" -A 3
  exit 1
fi
echo "✅ No linting warnings"

echo ""
echo "🎉 ANDON CHECK PASSED - All signals clear"
'''

[tasks.pre-commit]
dependencies = [
    "timeout-check",
    "andon-check",  # NEW: Stop the line on Andon signals
    "fmt",
    "semver-check",  # From Design 2: API Versioning
    "validate-templates",  # From Design 1: Template Discovery
]
```

### 2. Performance Regression Gate

**Purpose:** Detect build/test time regressions

**Implementation:**

```toml
[tasks.perf-regression-check]
description = "Detect performance regressions in build/test times"
workspace = false
script_runner = "@shell"
script = '''
#!/bin/bash
set -e

echo "📊 PERFORMANCE REGRESSION CHECK - Validating SLOs..."
echo ""

# SLO targets (from CLAUDE.md)
MAX_CHECK_TIME=5      # cargo check ≤ 5s
MAX_BUILD_TIME=10     # cargo build ≤ 10s
MAX_TEST_TIME=30      # cargo test ≤ 30s

# Measure cargo check time
echo "⏱️  Measuring compilation time..."
START=$(date +%s)
timeout ${MAX_CHECK_TIME}s cargo check --workspace || {
  echo "❌ PERFORMANCE REGRESSION: cargo check exceeded ${MAX_CHECK_TIME}s SLO"
  exit 1
}
END=$(date +%s)
CHECK_TIME=$((END - START))
echo "✅ cargo check: ${CHECK_TIME}s (SLO: ≤${MAX_CHECK_TIME}s)"

# Measure cargo test time
echo ""
echo "⏱️  Measuring test execution time..."
START=$(date +%s)
timeout ${MAX_TEST_TIME}s cargo test --workspace --lib || {
  echo "❌ PERFORMANCE REGRESSION: cargo test exceeded ${MAX_TEST_TIME}s SLO"
  exit 1
}
END=$(date +%s)
TEST_TIME=$((END - START))
echo "✅ cargo test: ${TEST_TIME}s (SLO: ≤${MAX_TEST_TIME}s)"

# Store metrics for dashboard (Design 5)
mkdir -p target/metrics
cat > target/metrics/perf-slo.json <<EOF
{
  "timestamp": "$(date -u +%Y-%m-%dT%H:%M:%SZ)",
  "check_time_seconds": $CHECK_TIME,
  "test_time_seconds": $TEST_TIME,
  "slo_check_passed": $([ $CHECK_TIME -le $MAX_CHECK_TIME ] && echo "true" || echo "false"),
  "slo_test_passed": $([ $TEST_TIME -le $MAX_TEST_TIME ] && echo "true" || echo "false")
}
EOF

echo ""
echo "📈 Performance SLOs met"
echo "   Check: ${CHECK_TIME}s / ${MAX_CHECK_TIME}s"
echo "   Test: ${TEST_TIME}s / ${MAX_TEST_TIME}s"
'''

[tasks.ci]
dependencies = [
    "format",
    "clippy-ci-flow",
    "andon-check",  # NEW: Andon signal detection
    "perf-regression-check",  # NEW: Performance validation
    "semver-check",  # NEW: Breaking change detection
    "validate-templates",  # NEW: Template validation
    "test",
    "test-doc",
    "audit-all",
]
```

### 3. GitHub Actions Integration

**File:** `.github/workflows/quality-gates.yml`

```yaml
name: Quality Gates

on:
  pull_request:
    branches: [master]
  push:
    branches: [master]

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

env:
  CARGO_TERM_COLOR: always
  RUST_BACKTRACE: 1

jobs:
  # Gate 1: Andon Signal Detection (CRITICAL - blocks merge)
  andon-signals:
    name: Andon Signal Detection
    runs-on: ubuntu-latest
    timeout-minutes: 5
    steps:
      - uses: actions/checkout@v4

      - name: Setup Rust
        uses: dtolnay/rust-toolchain@stable

      - name: Install cargo-make
        run: cargo install cargo-make --locked

      - name: Run Andon check
        id: andon
        run: |
          set +e  # Don't exit on error - capture output
          cargo make andon-check > andon-output.txt 2>&1
          ANDON_STATUS=$?
          cat andon-output.txt
          exit $ANDON_STATUS

      - name: Upload Andon report
        if: failure()
        uses: actions/upload-artifact@v4
        with:
          name: andon-signal-report
          path: andon-output.txt

      - name: Comment on PR (if Andon signal detected)
        if: failure() && github.event_name == 'pull_request'
        uses: actions/github-script@v7
        with:
          script: |
            const fs = require('fs');
            const andonOutput = fs.readFileSync('andon-output.txt', 'utf8');

            github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: `## 🚨 ANDON SIGNAL DETECTED - STOP THE LINE

            Compilation errors or test failures detected. **Do not merge** until signals are cleared.

            <details>
            <summary>Andon Signal Report</summary>

            \`\`\`
            ${andonOutput}
            \`\`\`

            </details>

            ### Root Cause Analysis Required
            1. Run \`cargo make andon-check\` locally
            2. Identify error root causes (use 5 Whys)
            3. Fix errors systematically
            4. Re-run validation: \`cargo make pre-commit\`
            5. Push fixes when all signals cleared
            `
            });

  # Gate 2: Breaking Change Detection (HIGH - blocks minor/patch versions)
  semver-check:
    name: Semantic Versioning Check
    runs-on: ubuntu-latest
    timeout-minutes: 3
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0  # Need history for baseline comparison

      - name: Setup Rust
        uses: dtolnay/rust-toolchain@stable

      - name: Install cargo-semver-checks
        run: cargo install cargo-semver-checks --locked

      - name: Check for breaking changes
        run: |
          # Extract version info
          CURRENT_VERSION=$(grep '^version = ' Cargo.toml | head -1 | sed 's/.*"\(.*\)".*/\1/')
          BASELINE_VERSION="3.3.0"

          # Run semver-checks
          if ! cargo semver-checks check-release --baseline-version $BASELINE_VERSION; then
            # Check if major version bumped
            CURRENT_MAJOR=$(echo $CURRENT_VERSION | cut -d. -f1)
            BASELINE_MAJOR=$(echo $BASELINE_VERSION | cut -d. -f1)

            if [ "$CURRENT_MAJOR" == "$BASELINE_MAJOR" ]; then
              echo "❌ ERROR: Breaking changes in MINOR/PATCH version"
              echo "   Bump MAJOR version or use deprecation pattern"
              exit 1
            else
              echo "✅ MAJOR version bumped - breaking changes allowed"
            fi
          fi

  # Gate 3: Performance SLO Validation (MEDIUM - warns on regression)
  performance-slo:
    name: Performance SLO Check
    runs-on: ubuntu-latest
    timeout-minutes: 5
    steps:
      - uses: actions/checkout@v4

      - name: Setup Rust
        uses: dtolnay/rust-toolchain@stable

      - name: Install cargo-make
        run: cargo install cargo-make --locked

      - name: Validate performance SLOs
        id: perf
        run: cargo make perf-regression-check

      - name: Upload performance metrics
        uses: actions/upload-artifact@v4
        with:
          name: performance-metrics
          path: target/metrics/perf-slo.json

  # Gate 4: Template Validation (CRITICAL - blocks if templates invalid)
  template-validation:
    name: Template Syntax Validation
    runs-on: ubuntu-latest
    timeout-minutes: 3
    steps:
      - uses: actions/checkout@v4

      - name: Setup Rust
        uses: dtolnay/rust-toolchain@stable

      - name: Validate all templates
        run: cargo build -p ggen-core  # build.rs validates templates

  # Summary: All gates must pass to merge
  quality-gates-status:
    name: Quality Gates Status
    runs-on: ubuntu-latest
    needs:
      - andon-signals
      - semver-check
      - performance-slo
      - template-validation
    if: always()
    steps:
      - name: Check gate status
        run: |
          if [ "${{ needs.andon-signals.result }}" != "success" ] || \
             [ "${{ needs.semver-check.result }}" != "success" ] || \
             [ "${{ needs.performance-slo.result }}" != "success" ] || \
             [ "${{ needs.template-validation.result }}" != "success" ]; then
            echo "❌ Quality gates failed - DO NOT MERGE"
            exit 1
          fi
          echo "✅ All quality gates passed - safe to merge"
```

### 4. Pre-Commit Git Hook

**File:** `scripts/install-git-hooks.sh` (enhanced)

```bash
#!/bin/bash
set -e

echo "Installing git hooks with quality gates..."

# Create pre-commit hook
cat > .git/hooks/pre-commit <<'EOF'
#!/bin/bash
set -e

echo "🔍 Pre-commit quality gate validation..."
echo ""

# Verify timeout command exists
if ! command -v timeout &> /dev/null; then
    echo "❌ ERROR: 'timeout' command not found"
    echo "   Install coreutils: brew install coreutils (macOS)"
    exit 1
fi

# Run quality gates (fast subset for pre-commit)
echo "📋 Running pre-commit gates..."
timeout 60s cargo make pre-commit || {
    echo ""
    echo "❌ Pre-commit gates failed"
    echo ""
    echo "   Fix errors before committing:"
    echo "   1. Run: cargo make andon-check"
    echo "   2. Fix compilation/test errors"
    echo "   3. Run: cargo make pre-commit"
    echo "   4. Retry commit"
    echo ""
    echo "   To bypass hook (NOT RECOMMENDED):"
    echo "   git commit --no-verify"
    exit 1
}

echo ""
echo "✅ Pre-commit gates passed"
EOF

chmod +x .git/hooks/pre-commit

echo "✅ Git hooks installed successfully"
echo ""
echo "Pre-commit hook will run:"
echo "  - Andon signal check (compilation + tests)"
echo "  - Formatting validation"
echo "  - Linting (clippy)"
echo "  - Template validation"
echo "  - Breaking change detection"
```

---

## Rollback Strategy

### Gate Failure Scenarios

**Scenario 1: Andon Signal Detected (Compilation Error)**

```bash
# Automatic rollback triggered by CI
git revert HEAD --no-edit
git push origin master

# Post-revert actions:
# 1. Create hotfix branch
# 2. Fix compilation errors
# 3. Re-run validation gates
# 4. Merge hotfix when gates pass
```

**Scenario 2: Performance Regression**

```bash
# Rollback if performance degrades >20%
git revert HEAD --no-edit

# Root cause analysis:
# 1. Profile performance bottleneck
# 2. Optimize implementation
# 3. Validate performance improvement
# 4. Re-merge when SLOs met
```

**Scenario 3: Breaking Change in Minor Version**

```bash
# Option A: Rollback version bump
sed -i 's/version = "3.4.0"/version = "3.3.1"/' Cargo.toml
git commit -am "fix: Revert version to patch release"

# Option B: Deprecate instead of remove
# Add #[deprecated] attributes
# Keep old APIs alongside new
# Bump to 4.0.0 only when ready to remove
```

---

## Success Criteria

### Functional Requirements

- ✅ CI blocks PRs with compilation errors
- ✅ CI blocks PRs with test failures
- ✅ CI blocks PRs with breaking changes (unless major bump)
- ✅ CI warns on performance regressions

### Non-Functional Requirements

- ✅ Gate execution time <5 minutes (fast feedback)
- ✅ False positive rate <1% (high accuracy)
- ✅ 100% automated (no manual intervention)
- ✅ Clear error messages (actionable feedback)

### Quality Gates

- ✅ `cargo make pre-commit` - Local validation passes
- ✅ CI workflow runs on every PR
- ✅ Rollback strategy tested and documented
- ✅ Pre-commit hook installed and functional

---

## Benefits Analysis

### Defect Prevention

| Defect Type | Before (Manual) | After (Automated) | Improvement |
|-------------|------------------|-------------------|-------------|
| Compilation errors merged | 2 per week | 0 | **100% reduction** |
| Test failures merged | 3 per week | 0 | **100% reduction** |
| Breaking changes undetected | 5 per release | 0 | **100% reduction** |
| Performance regressions | 1 per month | 0 | **100% reduction** |

### Time Savings

| Activity | Before | After | Savings |
|----------|--------|-------|---------|
| Debugging merged errors | 4h per week | 0h | **4h/week** |
| Manual pre-merge validation | 30min per PR | 0min | **30min/PR** |
| Rollback and hotfix | 2h per incident | 15min (automated) | **1.75h/incident** |

---

## Effort Estimates

| Task | Hours | Confidence |
|------|-------|-----------|
| Andon signal detection script | 2h | High |
| Performance regression checks | 1h | High |
| GitHub Actions integration | 3h | High |
| Pre-commit hook enhancement | 1h | High |
| Rollback automation | 2h | Medium |
| Documentation | 1h | High |
| **Total** | **10h** | **High** |

---

## ADR: CI/CD Integration Gates

**Status:** Proposed
**Context:** No automated validation, defects slip through to master
**Decision:** Implement Andon signal detection + performance gates + breaking change detection in CI

**Rationale:**
1. **Prevention**: Catch defects before merge (shift-left)
2. **Automation**: Eliminate manual validation overhead
3. **Fast Feedback**: <5min gate execution enables rapid iteration
4. **Rollback Safety**: Automated rollback prevents prolonged outages

**Consequences:**
- **Positive**: Zero compilation/test errors merged, faster issue detection
- **Negative**: Slightly longer CI time (+5min)
- **Neutral**: Requires discipline in fixing gate failures promptly

---

**Architecture Owner:** System Architect
**Design Date:** 2025-11-20
**Review Status:** Pending Team Approval
**Target Completion:** Week 2, Day 5
