Improving Code Review Processes

Code review is essential for quality but often becomes a bottleneck. Slow reviews block work, unclear feedback causes frustration, and inconsistent standards waste time. Improving code review requires technical solutions, clear guidelines, and cultural change.

Code Review Problems

Review Guidelines

What to Review

CODE REVIEW FOCUS AREAS
═══════════════════════

HIGH PRIORITY (human review):
─────────────────────────────────────
✓ CORRECTNESS
  ├── Does it do what it should?
  ├── Edge cases handled?
  ├── Error handling correct?
  └── Logic flaws?

✓ DESIGN
  ├── Right abstraction level?
  ├── Follows architecture?
  ├── Maintainable?
  └── Extensible?

✓ SECURITY
  ├── Injection vulnerabilities?
  ├── Authentication/authorization?
  ├── Sensitive data exposure?
  └── Input validation?

✓ TESTING
  ├── Tests cover changes?
  ├── Edge cases tested?
  ├── Tests readable?
  └── Tests maintainable?

AUTOMATE (not human review):
─────────────────────────────────────
✗ Formatting
✗ Style conventions
✗ Import ordering
✗ Unused variables
✗ Type errors
✗ Common bug patterns
└── All handled by linters/CI

PR Size Guidelines

PR SIZE BEST PRACTICES
══════════════════════

IDEAL PR SIZE:
├── < 200 lines changed
├── Single logical change
├── Reviewable in 15-30 minutes
└── One concept to understand

TOO BIG IF:
├── > 400 lines changed
├── Multiple unrelated changes
├── Takes > 1 hour to review
├── "Just one more thing" additions

HOW TO KEEP SMALL:
─────────────────────────────────────
1. Ship incrementally
   ├── Add skeleton first
   ├── Add logic in next PR
   └── Add tests in another

2. Separate refactors
   ├── Refactor first (separate PR)
   ├── Then add feature
   └── Easier to review each

3. Feature flags
   ├── Ship incomplete behind flag
   ├── Enable when ready
   └── No big-bang PRs

4. Stacked PRs
   ├── PR 1: Foundation
   ├── PR 2: Core feature (depends on 1)
   ├── PR 3: Polish (depends on 2)
   └── Each reviewable separately

Feedback Guidelines

GIVING GOOD FEEDBACK
════════════════════

TONE:
─────────────────────────────────────
❌ "This is wrong"
✓ "Consider using X because Y"

❌ "Why would you do this?"
✓ "I'd suggest X approach for maintainability"

❌ "Change this" (no reason)
✓ "Let's change X because it could cause Y issue"

CATEGORIZE COMMENTS:
─────────────────────────────────────
[Blocker] - Must fix before merge
[Suggestion] - Consider, but optional
[Nit] - Minor, up to you
[Question] - Need clarification

EXAMPLES:
"[Blocker] This SQL is vulnerable to injection.
Use parameterized query: [example code]"

"[Suggestion] This function is doing a lot.
Consider extracting the validation into a
separate method for readability."

"[Nit] Typo in variable name: 'recieve'"

"[Question] I'm not familiar with this pattern.
Can you explain why you chose it?"

PRAISE:
─────────────────────────────────────
Also include positive feedback:
├── "Nice refactor, much cleaner!"
├── "Good test coverage"
├── "Clever solution"
└── Balance criticism with appreciation

Process Improvements

Review SLA

CODE REVIEW SLA
═══════════════

TARGET TIMES:
├── First review: Within 4 hours
├── Follow-up review: Within 2 hours
├── Simple PR: Same day
├── Complex PR: Next business day

ENFORCEMENT:
─────────────────────────────────────
1. Track review time in GitScrum
2. Dashboard shows aging PRs
3. Slack reminder at 4 hours
4. Escalation at 8 hours
5. Report in team metrics

MAKING IT WORK:
├── Review is higher priority than new work
├── Check PRs before starting new task
├── Block calendar time for reviews
├── Rotate who reviews first
└── Celebrate fast reviews

EXCEPTIONS:
├── Large PRs (24h OK, but avoid large PRs)
├── Complex domain (24h OK)
├── Vacation/sick (reassign reviewer)
└── Document exception reason

Reviewer Rotation

REVIEWER ROTATION SYSTEM
════════════════════════

APPROACH 1: Round Robin
─────────────────────────────────────
Week 1: Sarah is primary reviewer
Week 2: Mike is primary reviewer
Week 3: Alex is primary reviewer
Repeat...

Primary reviewer takes first pass on all PRs

APPROACH 2: Expertise-Based
─────────────────────────────────────
Frontend changes → Emma or David
Backend changes → Sarah or Mike
Infrastructure → Alex or Jordan
Database → Sarah or Alex

Match reviewer to change type

APPROACH 3: Automatic Assignment
─────────────────────────────────────
GitHub CODEOWNERS:
/src/frontend/* @frontend-team
/src/api/* @backend-team
/infrastructure/* @devops-team

Auto-assigns based on files changed

APPROACH 4: Pair Rotation
─────────────────────────────────────
Each PR needs 1 reviewer
Assign rotating pair each week
Both share load evenly
Everyone reviews over time

Automation

Automated Checks

AUTOMATE BEFORE REVIEW
══════════════════════

CI PIPELINE CHECKS:
─────────────────────────────────────
# .github/workflows/pr.yml
on: [pull_request]

jobs:
  checks:
    runs-on: ubuntu-latest
    steps:
      # Formatting
      - run: npm run format:check
      
      # Linting
      - run: npm run lint
      
      # Type checking
      - run: npm run typecheck
      
      # Tests
      - run: npm run test
      
      # Security scan
      - run: npm audit
      
      # Coverage check
      - run: npm run test:coverage

IF ANY FAIL:
├── PR blocked from merge
├── Author fixes before review
├── Reviewer time not wasted
└── Consistent standards

REVIEWER ONLY REVIEWS IF CI PASSES

Review Tooling

CODE REVIEW TOOLS
═════════════════

GITSCRUM + GITHUB:
├── PR linked to task
├── Status synced to board
├── Time in review tracked
├── Metrics collected

GITHUB FEATURES:
├── CODEOWNERS for auto-assign
├── Branch protection rules
├── Required approvals
├── Status checks

ADDITIONAL TOOLS:
├── Danger: PR checklist automation
├── SonarQube: Code quality analysis
├── Codacy: Automated review
└── CodeClimate: Maintainability

SUGGESTED COMMENTS:
├── AI-assisted review suggestions
├── Catch common issues
├── Consistent feedback
└── Speed up reviewer

Cultural Improvements

Code Review Culture

HEALTHY REVIEW CULTURE
══════════════════════

PRINCIPLES:
─────────────────────────────────────
1. ASSUME GOOD INTENT
   "They're trying their best"
   Not: "Why did they do this wrong?"

2. CRITIQUE CODE, NOT PEOPLE
   "This code could be improved by..."
   Not: "You wrote this wrong"

3. EDUCATIONAL OPPORTUNITY
   Both author and reviewer learn
   Not: Gotcha/point scoring

4. EFFICIENCY FOCUSED
   Fast feedback helps everyone
   Not: Perfect at expense of speed

ANTI-PATTERNS TO AVOID:
├── Nitpicking style (automate it)
├── Ego-driven reviews
├── "I would have done it differently"
├── Requiring perfection
├── Ignoring PRs
├── Review bombing (all at once)
└── Gate-keeping behavior

POSITIVE PRACTICES:
├── Thank authors for good work
├── Explain the "why" of feedback
├── Offer to pair if complex
├── Respond quickly
├── Be open to discussion
└── Approve when good enough

Best Practices

For Code Review

1. Small PRs — Easier to review well
2. Review quickly — 4-hour target
3. Automate style — Focus humans on logic
4. Be kind — Critique code, not people
5. Prioritize reviews — Before new work

Anti-Patterns

CODE REVIEW MISTAKES:
✗ Large PRs (> 400 lines)
✗ Days to first review
✗ Manual style checking
✗ Mean or personal feedback
✗ Requiring perfection
✗ No clear standards
✗ Single reviewer bottleneck
✗ Review as afterthought

Related Solutions

• Reducing code review turnaround time
• Identifying bottlenecks in development workflow
• Developer workflow optimization