The Art of Code Review

4 min read
#Code Review#Team#Quality

Code review is where knowledge transfer, quality assurance, and team building intersect. Yet many teams treat it as a bureaucratic checkbox rather than an opportunity to elevate their craft.

Why Code Review Matters

Code review isn't about finding bugs (though that's a benefit). It's about:

  • Knowledge sharing: Spreading understanding across the team
  • Consistency: Ensuring code meets team standards
  • Learning: Finding better ways to solve problems
  • Culture: Building a collaborative, learning-focused team

Research shows that thoughtful code review reduces bugs by 30%, improves code quality significantly, and creates a stronger team culture.

The Reviewer's Mindset

Be Kind, Be Clear, Be Helpful

typescript
// ❌ Unhelpful review
"This is wrong. Use better variable names."

// ✅ Constructive review
"I found the variable names `x` and `temp` a bit unclear.
Consider something like `userIndex` and `previousValue` for clarity.
Here's why: [explanation]"

The best reviews explain the "why" behind suggestions, not just the "what."

Focus on the Important Stuff

Categorize feedback:

| Level | Example | Tone | |-------|---------|------| | Critical | Security vulnerabilities, logic errors | Blocking | | Important | Performance issues, maintainability | Should fix | | Nice to have | Alternative approaches, style suggestions | Suggestive | | Informational | FYI, context, good catches | Supportive |

Ask Questions

typescript
// ❌ Accusatory
"Why did you write this? It's inefficient."

// ✅ Curious
"I'm curious about the choice here—did you consider using a Set
for O(1) lookups instead of an Array? What trade-offs did you weigh?"

Questions show respect for the author's decisions while prompting deeper thinking.

The Author's Mindset

Receive Feedback Gracefully

Remember: criticism of your code isn't criticism of you. Your code is your work, not your identity.

When you receive feedback:

  1. Listen: Understand the reviewer's perspective
  2. Ask clarifying questions: Make sure you understand the concern
  3. Acknowledge: Even if you disagree, acknowledge the thought
  4. Respond: Explain your reasoning or fix the issue

Ask for Help

typescript
// Good practice: Ask for input on uncertain areas
// @reviewer: I'm not confident about this database query optimization.
// Thoughts on whether this change will cause performance issues?

const query = db.user
  .where({ active: true })
  .select({ id: true, name: true })
  .orderBy({ createdAt: "desc" })

Best Practices for Code Reviews

1. Keep PRs Small

PRs over 400 lines of code take exponentially longer to review and are more likely to miss bugs. Aim for 150-300 lines.

2. Automate the Tedious Stuff

bash
# Run these automatically, not in code review
npm run lint
npm run format
npm run test
npm run type-check

Focus your review on things humans are good at: logic, architecture, and maintainability.

3. Use Templates

markdown
## What does this PR do?

[Brief description]

## How to test?

- [ ] Step 1
- [ ] Step 2

## Related issues

Fixes #123

## Type of change

- [ ] Bug fix
- [ ] New feature
- [ ] Breaking change

4. Set Expectations

  • SLA for review: How long before expecting feedback?
  • Approval process: Who needs to approve?
  • Merge responsibility: Who merges (author or reviewer)?

Red Flags in Code Review

Watch for these patterns:

typescript
// ❌ Too much logic in one function
function processUserData(data) {
  // 50 lines of validation
  // 30 lines of transformation
  // 20 lines of formatting
  // 15 lines of API calls
}

// ✅ Broken into smaller functions
function validateUserData(data) { /* 10 lines */ }
function transformUserData(data) { /* 20 lines */ }
function formatUserData(data) { /* 15 lines */ }
function saveUserData(data) { /* 10 lines */ }

Creating a Review Culture

Lead by Example

  • Provide thoughtful, kind, detailed reviews
  • Ask questions instead of making statements
  • Acknowledge good code
  • Share learning moments

Make it Safe

Measure What Matters

Track:

  • Average review turnaround time
  • Team satisfaction with code review process
  • Bug detection rate
  • Time to merge

Conclusion

Code review is a skill that improves with practice and intention. The best teams treat reviews not as gatekeeping, but as collaboration and growth.

Every review is an opportunity to:

  • Make the codebase better
  • Help a teammate grow
  • Share knowledge across the team
  • Build trust and respect

Invest in making code review great, and your entire team—and codebase—will benefit.