Pull Request Best Practices: From Review to Merge

Pull requests are the backbone of modern software development. They're where code quality is maintained, knowledge is shared, and teams collaborate to build better software. Yet many teams struggle with inefficient PR processes that slow down development and frustrate developers.

Whether you're a seasoned engineer or new to collaborative development, mastering pull request best practices can dramatically improve your team's productivity and code quality. Let's dive into the complete lifecycle of a pull request and explore how to optimize each stage.

Creating Effective Pull Requests

Keep It Small and Focused

The golden rule of pull requests: smaller is better. Large PRs are harder to review, more likely to contain bugs, and take longer to merge. Aim for changes that can be reviewed in 15-20 minutes.

What makes a PR too large?

• More than 400 lines of code changes
• Multiple unrelated features or fixes
• Complex logic changes mixed with simple refactoring
• Changes spanning multiple architectural layers

Write Clear, Descriptive Titles and Descriptions

Your PR title is the first thing reviewers see. Make it count:

Good titles:

• Add user authentication middleware for API routes
• Fix memory leak in image processing pipeline
• Refactor database connection pooling for better performance

Poor titles:

• Fix bug
• Update code
• Changes

For descriptions, follow this template:

## What

Brief summary of what changed

## Why

Context and reasoning behind the change

## How

Technical approach and implementation details

## Testing

How the change was tested

## Screenshots/Videos

(If applicable)

Use Draft PRs for Work in Progress

Draft PRs are perfect for:

• Getting early feedback on your approach
• Running CI/CD pipelines before the code is ready
• Collaborating on complex features
• Showing progress on long-running tasks

Convert to a regular PR only when you're confident the code is ready for final review.

The Art of Code Review

What to Look For

Effective code reviews go beyond just checking if the code works. Here's what experienced reviewers focus on:

Functionality

• Does the code do what it's supposed to do?
• Are edge cases handled properly?
• Is error handling appropriate?

Code Quality

• Is the code readable and maintainable?
• Are naming conventions consistent?
• Is the code properly structured and organized?

Performance & Security

• Are there potential performance bottlenecks?
• Are security best practices followed?
• Could the code introduce vulnerabilities?

Testing

• Are there adequate tests for the changes?
• Do existing tests still pass?
• Are test cases comprehensive?

Providing Constructive Feedback

Great code reviews are collaborative, not confrontational. Here's how to provide feedback that helps rather than hinders:

Use the right tone:

• "Consider using a Map here for better performance" ✅
• "This is wrong, use a Map" ❌

Be specific:

• "This function could benefit from error handling for the case where the API returns null" ✅
• "Add error handling" ❌

Explain the why:

• "This variable name could be more descriptive to help future maintainers understand its purpose" ✅
• "Bad variable name" ❌

Review Categories

Not all feedback is created equal. Categorize your comments:

Responding to Review Feedback

Address All Comments

Even if you disagree with a comment, acknowledge it. Options include:

• Making the requested change
• Explaining why you chose a different approach
• Starting a discussion about the best solution
• Agreeing to address it in a future PR (if non-critical)

Push Back When Appropriate

Healthy disagreement leads to better code. If you believe your approach is better:

1. Explain your reasoning clearly
2. Provide evidence (performance benchmarks, examples, etc.)
3. Be open to compromise
4. Escalate to a team lead if needed

Merging Strategies

Choose the Right Merge Strategy

Merge Commit

• Preserves the complete history of the feature branch
• Best for: Feature branches with meaningful commit history
• Creates a merge commit that can be easily reverted

Squash and Merge

• Combines all commits into a single commit
• Best for: Feature branches with messy commit history
• Keeps main branch clean and linear

Rebase and Merge

• Replays commits from the feature branch onto main
• Best for: Clean, well-structured commit history
• Maintains linear history without merge commits

Pre-Merge Checklist

Before hitting that merge button:

• All CI/CD checks pass
• All review comments are addressed
• Required approvals are obtained
• Branch is up to date with main
• Documentation is updated if needed
• Breaking changes are communicated

Automating PR Workflows

Use PR Templates

Create .github/pull_request_template.md to standardize PR descriptions:

## Description

Brief summary of changes

## Type of Change

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

## Testing

- [ ] Unit tests pass
- [ ] Integration tests pass
- [ ] Manual testing completed

## Checklist

- [ ] Code follows style guidelines
- [ ] Self-review completed
- [ ] Documentation updated

Leverage Branch Protection Rules

Protect your main branch with rules like:

• Require PR reviews before merging
• Require status checks to pass
• Require branches to be up to date
• Restrict who can push to the branch

Common PR Antipatterns to Avoid

The "Everything PR"

Trying to fix multiple unrelated issues in one PR. This makes reviews difficult and increases the risk of introducing bugs.

The "Silent Treatment"

Creating a PR without context or description. Reviewers shouldn't have to guess what your code does.

The "Perfectionist Trap"

Spending hours on minor style issues while ignoring significant architectural problems.

The "Approval Collector"

Seeking approvals from everyone instead of the right people. More approvals don't necessarily mean better code.

Measuring PR Success

Track these metrics to improve your PR process:

• Time to First Review: How quickly do PRs get initial attention?
• Review Cycle Time: How long from creation to merge?
• Review Coverage: What percentage of code gets reviewed?
• Defect Escape Rate: How many bugs make it to production?

Building a Review Culture

Make Reviews a Priority

• Set expectations for review turnaround times
• Recognize great reviewers, not just great code authors
• Include review quality in performance evaluations
• Rotate review responsibilities to spread knowledge

Foster Learning

Use PRs as teaching opportunities:

• Junior developers should review senior code
• Share interesting solutions in team meetings
• Document common patterns discovered in reviews
• Celebrate when reviews catch significant issues

Conclusion

Mastering pull requests is about more than just code—it's about building a culture of collaboration, quality, and continuous improvement. Great PR practices lead to:

• Higher code quality and fewer bugs
• Better knowledge sharing across the team
• Faster development cycles
• Improved team communication
• More maintainable codebases

Remember, the goal isn't perfect PRs—it's continuous improvement. Start with one or two practices from this guide and gradually build better habits across your team.

The investment in better PR processes pays dividends in reduced technical debt, fewer production issues, and a more collaborative engineering culture. Your future self (and your teammates) will thank you.

Want to learn more about optimizing your development workflow? Check out our guides on Code Review Automation and Engineering Metrics That Matter.