Master the Code Review Best Practices for Quality 2025

Supercharge Your Code Reviews

Code reviews are crucial for delivering high-quality software. This listicle presents eight code review best practices to optimize your workflow and improve your team's output. Learn how to implement practical techniques like pull request size management, automated code quality checks, and constructive feedback to make your code reviews more efficient and effective. Following these code review best practices will help reduce bugs, improve code maintainability, and foster knowledge sharing across your team. Dive in to discover how to maximize the impact of your code review process.

1. Pull Request Size Management

Effective code review is a cornerstone of high-quality software development. A critical factor in achieving effective reviews lies in managing the size of your pull requests (PRs). Keeping PRs small and focused is crucial for enabling thorough reviews, faster feedback cycles, and ultimately, better code. Smaller PRs are easier to digest, allowing reviewers to understand the context, identify potential issues, and provide more valuable feedback. The ideal PR concentrates on a single task or feature and contains only the necessary changes to implement it. This targeted approach reduces cognitive load for reviewers and improves the overall quality of the review process, contributing significantly to code review best practices.

A well-managed PR size facilitates several key features: a limited scope (ideally under 400 lines of changed code), adherence to a single responsibility or purpose, clear separation of concerns within the codebase, and a series of logical, atomic commits. These attributes contribute to a streamlined review process. Companies like Google (with a ~200 line limit), Microsoft's Azure DevOps team (recommending under 400 lines), and Facebook (encouraging PRs reviewable in ~30 minutes) all emphasize the importance of concise PRs. These examples highlight how prioritizing smaller, focused changes benefits even the largest and most complex software projects. Learn more about Pull Request Size Management.

This approach offers a range of advantages:

• Faster review cycles and quicker feedback: Smaller PRs are naturally faster to review, enabling quicker turnaround times for feedback and accelerating the development process.
• Higher quality reviews with fewer missed issues: Reviewers can focus their attention more effectively on a smaller set of changes, increasing the likelihood of catching potential bugs or design flaws.
• Easier to understand context and purpose: With a limited scope, reviewers can grasp the intent and impact of the changes more readily, leading to more informed feedback.
• Simplified merge conflict resolution: Smaller PRs minimize the chances of merge conflicts arising, and when they do occur, they are typically easier to resolve.
• Better historical tracking in version control: A series of small, focused commits provides a clear and granular history of the code's evolution, making it easier to understand the rationale behind changes and facilitating debugging or rollback if needed.

However, managing PR size also presents some potential drawbacks:

• May require breaking down work more deliberately: Implementing this practice often requires developers to plan and structure their work more carefully, which can initially feel like added overhead.
• Could increase total number of PRs to manage: While individual PRs are smaller, the total number of PRs might increase for a given project. This can require adjustments to workflow and tooling for efficient management.
• Might not always be possible for certain large-scale refactorings: While the general principle holds true, some large-scale refactorings or complex features may necessitate larger PRs. In such cases, extra care should be taken to structure the changes logically and provide ample documentation for reviewers.

To effectively implement PR size management, consider these actionable tips:

• Split large changes into a series of smaller, logical PRs: Focus each PR on a well-defined subtask or aspect of the overall change.
• Create preparatory PRs that set up infrastructure before implementing features: This helps isolate infrastructure changes and simplifies the review of subsequent feature-related PRs.
• Use feature flags to separate merging code from activating functionality: This allows code to be merged into the main branch without immediately impacting users, giving more time for testing and validation.
• Consider the 'boy scout rule' - leave the code better than you found it, but in small increments: Make small, incremental improvements to existing code as part of your regular work, rather than accumulating large refactorings.

Pull request size management is a crucial aspect of code review best practices, directly impacting the effectiveness and efficiency of the review process. By embracing smaller, focused PRs, teams can foster a culture of high-quality code, faster development cycles, and more collaborative development workflows. This approach aligns well with agile methodologies and modern development practices, proving its value across a variety of software projects, from small startups to large enterprises. This technique is highly relevant to Data Scientists, System Administrators, DevOps Engineers, DevEx Engineers, Cloud Engineers, Software Engineers, Mobile Engineers (Android and iOS), Engineering Managers, Agile Coaches, Product Managers, Risk and Compliance professionals, Computer Science Teachers, and IT Analysts – essentially anyone involved in the software development lifecycle.

2. Automated Code Quality Checks

Among the most crucial code review best practices is the integration of automated code quality checks. This process leverages various tools to automatically verify code quality before it reaches a human reviewer. By catching basic issues early, automated checks free up human reviewers to focus on more substantive problems like architecture, logic, and overall design. This significantly improves the efficiency and effectiveness of code reviews. These checks encompass a range of functionalities, including linters for style and syntax, formatters for consistent code presentation, static analysis tools for detecting potential bugs and vulnerabilities, and automated tests to validate functionality.

Automated code quality checks work by scanning the codebase against predefined rules and standards. These rules can cover a wide spectrum, from simple stylistic choices (like indentation and naming conventions) to complex logic errors and potential security vulnerabilities. When a violation is detected, the tool flags it, often with a detailed explanation of the issue and suggestions for remediation. This immediate feedback loop helps developers address problems quickly and learn best practices.

Features of effective automated code quality systems:

• Pre-commit hooks for local validation: These prevent developers from committing code that violates established standards, catching issues before they even reach the repository.
• CI/CD pipeline integration: Integrating checks into the Continuous Integration/Continuous Delivery pipeline ensures that every code change is automatically validated before deployment.
• Automated testing (unit, integration, etc.): Testing ensures that the code functions as expected and helps identify regressions introduced by new changes.
• Static code analysis: This examines the code without actually executing it, identifying potential bugs, performance bottlenecks, and security vulnerabilities.
• Code style enforcement: This ensures a consistent code style across the entire codebase, improving readability and maintainability.
• Security vulnerability scanning: Automated tools can scan for known security vulnerabilities in code and dependencies, helping prevent security breaches.

Pros:

• Catches trivial issues before human review: This frees up human reviewers to focus on higher-level aspects of the code.
• Ensures consistent code style across the codebase: This enhances readability and collaboration.
• Identifies potential bugs and security vulnerabilities early: Early detection reduces the cost and effort of fixing issues later in the development cycle.
• Reduces reviewer fatigue by handling mechanical checks: This allows reviewers to concentrate on more complex and critical aspects of the code.
• Provides objective, consistent evaluation: Unlike human review, automated checks apply the same rules and standards consistently.

Cons:

• Initial setup time and maintenance overhead: Configuring and maintaining these tools requires time and effort.
• Potential for false positives: Tools may flag issues that are not actually problems, requiring developers to investigate and potentially override the warnings.
• May slow down the development process if overtly strict: Overly strict rules can lead to unnecessary friction and slow down development.
• Can lead to overreliance on tools instead of critical thinking: Developers should not rely solely on tools and must still engage in critical thinking and manual review.

Examples of successful implementation:

• Google uses Tricorder to run automated analyses on code changes.
• Microsoft employs CodeFlow with integrated static analysis.
• Netflix uses a suite of automated tools called Spinnaker for continuous delivery.

Tips for effective implementation:

• Configure tools to match team coding standards: Customize the rules and standards to align with your team's specific needs and preferences.
• Start with essential checks and gradually add more sophisticated ones: Don't try to implement everything at once. Start with the most important checks and gradually add more as your team gains experience.
• Ensure all team members understand how to run checks locally: This allows developers to catch issues before pushing code for review.
• Regularly review and update rule sets to prevent outdated checks: Ensure that the rules and standards are up-to-date and relevant to your project.
• Document reasons for any disabled rules to maintain institutional knowledge: If certain rules are disabled, document the reasons clearly so that the decision can be revisited later.

Popular Tools & Platforms:

• SonarQube: Offers a comprehensive code quality platform.
• ESLint: A widely used linter in JavaScript ecosystems.
• RuboCop: A popular linter for Ruby communities.
• GitHub Actions: Facilitates workflow automation, including automated code quality checks.
• JetBrains IDEs: Offer built-in code analysis capabilities.

Automated code quality checks deserve a prominent place in any list of code review best practices because they significantly improve the efficiency and effectiveness of the review process. By automating mundane checks and providing immediate feedback, these tools empower developers to write better code and free up human reviewers to focus on the more nuanced aspects of software development. This ultimately leads to higher quality code, faster development cycles, and more robust applications.

3. Review Checklists

One of the most effective ways to elevate your code review best practices is by implementing review checklists. This systematic approach ensures consistency and thoroughness by guiding reviewers through a standardized set of checks, preventing crucial aspects from being overlooked. Instead of relying solely on individual memory or ad-hoc reviews, checklists provide a structured framework, prompting reviewers to consider common issues related to design, functionality, security, performance, and maintainability.

These checklists can be customized to align with specific programming languages, frameworks, or internal company standards, further enhancing their effectiveness. For instance, a checklist for Python code might include specific checks for proper use of decorators or list comprehensions, while a checklist for a web application might focus on security vulnerabilities like cross-site scripting (XSS) or SQL injection. This adaptability is key to addressing the unique challenges posed by different technology stacks and project requirements. Progressive levels of review depth can also be incorporated. For example, a junior developer's checklist might prioritize basic code style and functionality, while a senior developer's checklist could delve into more complex architectural considerations and performance optimization. Formalizing your code review process with a well-defined set of best practices can significantly improve code quality and team efficiency. For a comprehensive guide on establishing effective code review best practices, check out this article: Best Code Review Practices: A Definitive Guide to Building Quality Software from Mergify.

The benefits of using checklists are numerous. They promote consistent review quality across different reviewers, reducing variability and ensuring that code adheres to established standards. They also lessen the cognitive load on reviewers by providing a clear structure and reducing the need to remember every potential issue. Moreover, checklists serve as excellent training material for new team members, quickly familiarizing them with best practices and common pitfalls. Learn more about Review Checklists for specific examples and templates.

While checklists are a powerful tool, they also have potential drawbacks. If applied rigidly without thoughtful consideration, they can become a mere box-ticking exercise, failing to capture more nuanced issues. Regular updates are essential as technology and best practices evolve. Furthermore, highly specialized or unique problems not covered by standard checklist items might be missed.

Several prominent organizations exemplify the successful implementation of review checklists. Google’s code review checklist includes design, functionality, complexity, and tests, emphasizing a holistic approach. NASA's Jet Propulsion Laboratory (JPL) employs mission-critical safety checklists in its coding standards, highlighting the importance of rigorous checks in high-stakes environments. Square's checklist focuses on security, performance, and maintainability, reflecting their priorities as a financial services company.

Tips for Effective Checklist Implementation:

• Create specialized and general sections: Include sections specific to your chosen programming language alongside general sections covering broader aspects like code style, documentation, and testing.
• Prioritize security: Integrate security-focused items appropriate to your application's domain and risk profile.
• Regularly review and update: Quarterly reviews and updates based on lessons learned and evolving best practices ensure the checklist remains relevant and effective.
• Keep it concise: Avoid overly long checklists to prevent review fatigue and maintain focus on critical items.
• Automate where possible: Integrate automated checks for style and basic errors to free up reviewers to focus on higher-level aspects.

The efficacy of checklists has been widely recognized, notably through Atul Gawande's book "The Checklist Manifesto," which highlights their power in various fields. Organizations like OWASP (Open Web Application Security Project) provide valuable security review checklists, and companies like Basecamp, championed by Jason Fried and DHH, have integrated checklists into their development workflows. By adopting and adapting these principles, development teams can significantly enhance code quality, reduce errors, and foster a more consistent and efficient code review process.

4. Constructive Feedback Techniques

Effective code review hinges on how feedback is delivered. Constructive feedback techniques are crucial for code review best practices because they prioritize specific, objective, and solution-oriented communication rather than personal criticism. This approach cultivates a positive review culture that fosters collaboration, learning, and improvement. It shifts the focus from blame to shared responsibility for code quality, making reviews a valuable learning experience for everyone involved.

This method emphasizes separating the code from the coder, ensuring feedback targets the code itself and not the individual's abilities. Instead of accusatory statements, constructive feedback focuses on actionable suggestions for improvement. A balanced approach that highlights both positive aspects and areas for improvement further reinforces a growth mindset. Rather than issuing directives, a question-based approach encourages dialogue and shared understanding. Finally, grounding feedback in the business impact and user experience reminds reviewers of the ultimate goals of the code.

Features of constructive code review feedback include:

• Separation of code from coder: Critique the code, not the person who wrote it.
• Specific, actionable feedback: Provide concrete examples and suggest clear improvements.
• Balanced positive and improvement comments: Acknowledge good practices alongside areas for enhancement.
• Question-based approach rather than directives: Encourage discussion and shared understanding. "Have you considered using a dictionary here for faster lookups?" is more collaborative than "Change this to use a dictionary."
• Focus on business impact and user experience: Frame feedback within the larger context of the project goals.

Examples of Successful Implementation:

• Etsy: Emphasizes asking questions over making demands in code reviews.
• Atlassian: Uses a feedback model based on observations, impacts, and suggestions (OIS).
• Buffer: Publicly documents their emphasis on positive, growth-oriented feedback.

Actionable Tips for Readers:

• Use "we" language instead of "you": This fosters a sense of shared responsibility. For example, "We could improve readability here" sounds more collaborative than "You need to improve readability here."
• Explain the reasoning behind feedback: Don't just state what to change, explain why. This helps the code author understand the context and learn from the feedback.
• Phrase critiques as questions: This encourages discussion and avoids sounding dictatorial. "What are the performance implications of this approach?" is better than "This will be slow."
• Acknowledge good practices: Highlighting what's working well reinforces positive behaviors.
• Refer to coding principles rather than personal preferences: Base feedback on established standards and best practices. Instead of "I don't like this formatting," say "This formatting doesn't adhere to our style guide."
• Suggest specific alternatives when identifying issues: Don't just point out problems; offer concrete solutions.

When and Why to Use This Approach:

Constructive feedback should be the default approach for all code reviews. It's particularly beneficial when working with junior developers, onboarding new team members, or tackling complex projects. While it might require more effort initially, the long-term benefits of improved code quality, increased team morale, and a stronger learning culture far outweigh the costs.

Pros:

• Builds trust among team members
• Increases willingness to participate in code reviews
• Fosters knowledge sharing and learning
• Reduces defensive responses to feedback
• Creates psychological safety for innovation

Cons:

• Can be challenging to maintain during high-pressure situations
• May require additional training for team members
• Cultural and language differences can complicate implementation

This approach to code review best practices is informed by:

• Radical Candor framework by Kim Scott: This framework emphasizes caring personally and challenging directly.
• Nonviolent Communication principles by Marshall Rosenberg: Focuses on empathy and understanding in communication.
• Carol Dweck's growth mindset research: Encourages a belief in the potential for continuous improvement.

By incorporating constructive feedback techniques into your code review process, you can create a more collaborative, productive, and ultimately, more successful development environment. This method benefits everyone involved, from junior developers learning the ropes to seasoned engineers honing their skills.

5. Clear Review Expectations and SLAs

One of the most critical code review best practices is establishing clear expectations and Service Level Agreements (SLAs). This clarity ensures efficient code reviews, maintains a healthy development velocity, and ultimately contributes to higher quality code. Without agreed-upon standards, the review process can become a bottleneck, leading to frustration, delays, and potentially, a decrease in code quality. This section explains why and how to define crystal-clear expectations for your code review process.

Clear expectations encompass several key aspects:

• Defined response time expectations: How quickly should a reviewer provide initial feedback on a pull request (PR)? This should be a reasonable timeframe that balances the reviewer's other responsibilities with the need to keep the development process flowing.
• Clear review depth guidelines: What level of scrutiny is expected? Should reviewers be checking for every possible edge case, or is the focus on overall architecture and potential bugs? Clear guidelines prevent reviewers from getting bogged down in minutiae or, conversely, from performing superficial reviews.
• Escalation paths for blocked reviews: What happens if a reviewer is unavailable or a disagreement arises? A defined escalation path ensures that reviews don't stall indefinitely.
• Role-based responsibilities: Are there different expectations for senior engineers versus junior engineers? Clarifying roles and responsibilities helps everyone understand their part in the process.
• Metrics tracking for review process health: Tracking metrics like time-to-first-response and PR lifetime provides valuable data for identifying bottlenecks and areas for improvement.

Why are clear expectations and SLAs a code review best practice?

This approach directly addresses several common code review challenges. It reduces waiting time and development bottlenecks by setting expectations for timely feedback. It creates accountability for both authors and reviewers, ensuring that PRs are submitted and reviewed promptly. Clear expectations for all team members lead to a smoother and more predictable development process. Furthermore, tracking review metrics provides valuable insights that can be used to identify process improvement opportunities.

Examples of Successful Implementation:

Several prominent tech companies have embraced this best practice:

• Google: Expects initial feedback within 24 hours, ensuring that PRs don't languish and developers receive timely input.
• LinkedIn: Developed a "No PR Left Behind" culture with same-day review targets, emphasizing the importance of rapid feedback loops.
• Shopify: Uses a rotation system to ensure reviews are always covered, distributing the workload and preventing bottlenecks.

Actionable Tips for Implementation:

• Set realistic SLAs based on team capacity: Don't aim for unrealistic targets. Start with a reasonable timeframe, such as initial response within 4 working hours, and adjust as needed.
• Create a calendar for review rotation if using that approach: This ensures a fair distribution of review responsibilities and prevents individuals from being overloaded.
• Use PR templates to streamline the review process: Templates can guide authors in providing necessary context and information, making the review process more efficient.
• Track metrics like time-to-first-response and PR lifetime: These metrics provide objective data for evaluating the health of the review process.
• Schedule regular retrospectives to adjust SLAs based on team feedback: SLAs should not be static. Regularly review and adjust them based on team experience and feedback.
• Consider time zone differences for distributed teams: Establish SLAs that are fair and practical for all team members, regardless of their location.

Pros and Cons:

Pros:

• Reduces waiting time and development bottlenecks
• Creates accountability for both authors and reviewers
• Sets clear expectations for all team members
• Helps predict and manage development timelines
• Identifies process improvement opportunities

Cons:

• May create pressure that reduces review quality (if SLAs are too aggressive)
• Could be perceived as too rigid in some development cultures
• Requires tracking and occasional enforcement

Popularized By:

The importance of clear expectations and SLAs has been highlighted by various methodologies and movements:

• Agile methodology: Focuses on removing blockers and streamlining the development process.
• DevOps movement: Emphasizes flow and continuous delivery, requiring efficient and predictable code reviews.
• DORA metrics: Provide benchmarks for high-performing engineering teams, including metrics related to code review efficiency.

By implementing clear review expectations and SLAs, engineering teams can foster a more efficient, predictable, and ultimately, higher-quality development process. This code review best practice, while requiring some initial effort to establish, pays dividends in the long run by reducing friction, improving communication, and ultimately delivering better software.

6. Multi-Perspective Reviews: Ensuring Comprehensive Code Quality

Multi-perspective reviews represent a crucial code review best practice that elevates code quality by incorporating diverse viewpoints and expertise. This approach involves engaging multiple reviewers with complementary skills and backgrounds to examine code changes from different angles, including functionality, security, performance, maintainability, and user experience. By leveraging the collective knowledge of a diverse team, multi-perspective reviews help identify a broader range of potential issues and ensure a more robust and reliable end product. This technique is particularly valuable for code review best practices, as it encourages thoroughness and reduces the risk of overlooking critical flaws.

How it Works:

The core principle of multi-perspective reviews is to assign reviewers with specific areas of expertise to focus on different aspects of the code. For instance, a security expert would scrutinize the code for vulnerabilities, a performance engineer would analyze its efficiency, and a UX specialist would evaluate the user interface implications. This specialized approach ensures that each aspect of the code receives appropriate attention from a qualified reviewer.

Features of Multi-Perspective Reviews:

• Multiple reviewers with complementary expertise: Assemble review teams with individuals possessing diverse skill sets relevant to the code changes.
• Role-based review focuses: Assign specific review areas (security, UX, performance, etc.) to individual reviewers.
• Rotating reviewer assignments: Distribute the workload and expose team members to different code areas.
• Diverse seniority levels in review teams: Pair junior and senior developers for knowledge transfer and mentorship.
• Cross-functional participation: Involve stakeholders from different departments (e.g., product, design) for a holistic review.

Pros:

• Catches a wider range of issues: Multiple perspectives increase the likelihood of identifying bugs, security flaws, performance bottlenecks, and usability issues that a single reviewer might miss.
• Spreads knowledge and improves team skills: Reviewers learn from each other's expertise, leading to improved overall team competency.
• Reduces individual reviewer bias: Diverse perspectives help mitigate the impact of personal biases and preferences on the review process.
• Provides learning opportunities for junior team members: Working alongside senior reviewers allows junior developers to gain valuable experience and improve their code review skills.
• Ensures critical code receives comprehensive scrutiny: High-risk or complex code benefits significantly from the thoroughness of multiple reviews.

Cons:

• Can slow down the review process: Coordinating multiple reviewers can introduce delays compared to a single reviewer.
• Coordination challenges: Scheduling and managing feedback from multiple reviewers requires careful organization.
• Potential for diluted responsibility: Clearly defined roles and a primary reviewer are essential to avoid ambiguity in accountability.
• Higher workload for the team: More reviewers mean more time spent on reviews, potentially increasing the overall team workload.

Examples of Successful Implementation:

• Microsoft's Azure team: Employs dedicated security reviewers for authentication-related code changes.
• Airbnb: Includes frontend specialists and accessibility experts in the review process for UI/UX changes.
• Uber: Utilizes performance engineers to review code impacting critical application paths.

Tips for Effective Multi-Perspective Reviews:

• Scale reviewer count based on risk and complexity: More complex changes warrant more reviewers.
• Clearly define each reviewer's focus: Provide explicit instructions on what aspects each reviewer should prioritize.
• Use a primary reviewer for coordinating feedback: A designated lead reviewer can streamline communication and consolidate feedback.
• Consider pairing junior and senior developers: Foster knowledge transfer and mentorship opportunities.
• Create specialty tags to route pull requests to appropriate experts: Automate the assignment of reviewers based on code changes.
• Balance workload by rotating reviewer assignments: Ensure fair distribution of review responsibilities across the team.

Popularized By:

• AWS's principal engineer review process: Amazon Web Services emphasizes high-level review for critical systems.
• Two-person rule in critical systems: Commonly used in finance and other sensitive domains for enhanced security.
• Open source maintainer review patterns: Open source projects often utilize multiple maintainers with different areas of expertise for code reviews.

Why Multi-Perspective Reviews Deserve a Place in the List:

Multi-perspective reviews represent a fundamental shift from individual code scrutiny to a collaborative approach. By incorporating diverse expertise and viewpoints, this technique strengthens the code review process, reduces the risk of critical errors, and fosters a culture of shared responsibility for code quality. For data scientists, DevOps engineers, software engineers, and engineering managers alike, multi-perspective reviews offer a valuable strategy for building more robust, reliable, and maintainable software. This method is a cornerstone of code review best practices, ensuring comprehensive evaluation and ultimately contributing to higher quality code.

7. Knowledge Sharing During Reviews

Code review is often seen as a quality gate, a final check before code merges into the main branch. However, reframing code review as a knowledge-sharing opportunity elevates it from a necessary step to a powerful tool for team growth and improved code quality. This best practice, Knowledge Sharing During Reviews, emphasizes explaining the "why" behind code decisions, teaching patterns, and fostering a collective understanding of the codebase within the team. This approach is crucial for anyone striving to implement code review best practices.

Instead of simply checking for bugs or style violations, Knowledge Sharing During Reviews focuses on building understanding. This means providing detailed context in pull request (PR) descriptions, explaining the underlying principles guiding the code changes, referencing relevant documentation or established patterns, highlighting non-obvious decisions, and offering educational comments that go beyond mere fixes.

How it Works:

Knowledge Sharing During Reviews transforms the review process into a two-way conversation. The code author sets the stage by providing ample context and explanation within the PR description. Reviewers, in turn, engage not just by pointing out potential issues but also by asking clarifying questions, sharing related resources, and offering alternative approaches. This interactive dialogue fosters learning for both the author and the reviewers.

Examples of Successful Implementation:

• Stripe: Known for its robust engineering culture, Stripe exemplifies this practice by meticulously documenting architectural decisions and trade-offs directly within PR descriptions. This creates a valuable record of the reasoning behind key choices, accessible to all engineers.
• GitLab: GitLab's transparent review process, with its publicly accessible merge requests, offers a wealth of learning resources. Engineers can learn from the discussions and decisions made in past reviews, promoting a culture of shared knowledge.
• Basecamp: Basecamp leverages code reviews to document recurring patterns and best practices for future reference. This reduces code duplication and ensures consistency across the codebase.

Actionable Tips for Implementing Knowledge Sharing During Reviews:

• Create PR templates: Standardize PR descriptions with templates that prompt authors to provide context, explain their reasoning, and highlight learning points.
• Document "why" not just "what": In comments, explain the rationale behind suggested changes, rather than just stating the change itself.
• Share relevant articles or documentation links: Supplement review comments with links to helpful resources that further explain concepts or best practices.
• Take time to explain complex solutions: Instead of simply approving complex code, take the time to explain the intricacies to reviewers, ensuring everyone understands the approach.
• Consider pair programming sessions: For particularly complex or educational changes, pair programming can be a highly effective way to share knowledge and build understanding before the code even reaches the review stage.
• Periodically review closed PRs for learning opportunities: Closed PRs, rich with discussions and decisions, can serve as valuable learning resources for the entire team. Schedule regular sessions to revisit closed PRs and extract key takeaways.

Pros and Cons:

Pros:

• Accelerates team learning and onboarding: New team members quickly gain valuable insights into the codebase and the team's coding practices.
• Reduces knowledge silos and bus factor: Shared understanding distributes knowledge across the team, mitigating the risk of critical information being held by only a few individuals.
• Improves code quality through shared understanding: Deeper insights lead to better design decisions and fewer bugs.
• Creates documentation through review conversations: The discussions within code reviews effectively document the rationale behind code choices.
• Builds mentoring relationships naturally: The review process becomes an opportunity for senior engineers to mentor junior members, fostering a supportive learning environment.

Cons:

• Can increase time spent on reviews: Thorough explanations and discussions naturally require more time.
• May feel redundant for experienced team members: In some cases, experienced team members might find the detailed explanations unnecessary.
• Requires intentional effort to maintain: Cultivating a culture of knowledge sharing requires ongoing commitment and effort from the entire team.

Why This Item Deserves Its Place in the List:

Knowledge Sharing During Reviews fundamentally shifts the perspective on code review. It recognizes the immense learning potential inherent in the process and transforms it into a powerful engine for team growth and continuous improvement. By embracing this best practice, teams can build a stronger collective understanding of their codebase, foster a more collaborative environment, and ultimately produce higher-quality software. Learn more about Knowledge Sharing During Reviews. This approach, popularized by philosophies like Etsy's Code as Craft, Martin Fowler's emphasis on self-documenting code and processes, and Kent Beck's Extreme Programming practices, is a core component of modern, high-performing engineering teams. By integrating these code review best practices into your workflow, you can unlock the full potential of your team and your codebase.

8. Review-Friendly Code Organization

Effective code review is a cornerstone of high-quality software development. However, a disorganized and difficult-to-follow code submission can significantly hinder the review process, leading to missed bugs, frustration, and wasted time. Review-friendly code organization, a crucial code review best practice, puts the onus on the code author to structure their changes to facilitate a smooth and effective review. This approach not only benefits the reviewer but also leads to better overall code quality and improved team collaboration.

This practice involves structuring your code changes logically, providing comprehensive documentation, and creating a self-explanatory structure that simplifies the reviewer's job. It’s about treating your reviewer's time and attention with respect. Instead of presenting a monolithic block of changes, you present a clear, concise, and easily digestible narrative of your work.

Features of Review-Friendly Code Organization:

• Logical, Atomic Commits with Clear Messages: Breaking down changes into small, focused commits makes it easier to understand the evolution of the code and pinpoint specific modifications. Clear, concise commit messages explain the why behind each change, not just the what.
• Comprehensive PR Descriptions with Context: A well-written pull request (PR) description provides the reviewer with vital context, including the purpose of the changes, the problem being solved, and any relevant background information.
• Self-Documenting Code with Clear Naming: Meaningful variable, function, and class names reduce the need for excessive comments and make the code easier to understand.
• Strategic Comments for Complex Sections: While self-documenting code is ideal, well-placed comments can clarify intricate logic or non-obvious decisions.
• Before/After Comparisons Where Helpful: For UI changes or significant refactoring, providing before/after comparisons (e.g., screenshots, videos, or code diffs) can dramatically improve understanding.

Pros:

• Reduces Review Time and Cognitive Load: Reviewers can quickly grasp the changes and their impact, leading to faster and more efficient reviews.
• Increases Likelihood of Catching Issues: Clear, well-organized code makes it easier to identify potential bugs, security vulnerabilities, and performance bottlenecks.
• Creates Better Documentation for Future Developers: Well-structured commits and PR descriptions serve as valuable documentation for future maintainers.
• Shows Respect for Reviewers' Time and Attention: By presenting well-organized changes, you demonstrate respect for your colleagues and their valuable time.
• Speeds up the Overall Review Process: Streamlined reviews lead to faster integration of changes and quicker release cycles.

Cons:

• Requires Additional Preparation Time from Authors: Organizing code and writing detailed documentation takes time and effort upfront.
• May Need Training and Examples to Implement Effectively: Developers may require training and guidance to adopt these practices effectively.
• Can be Challenging to Retrofit to Existing Workflows: Integrating review-friendly practices into established workflows can be challenging and may require adjustments.

Examples of Successful Implementation:

• Linux Kernel Development: The Linux kernel community's email-based patch submission process emphasizes clear, concise patches with detailed explanations. Linus Torvalds' stringent review process has heavily influenced code review best practices.
• Facebook: Facebook utilizes sophisticated diff visualization tools to simplify code review and highlight the impact of changes.
• thoughtbot: thoughtbot, a prominent software consultancy, employs PR template systems to ensure consistent context and structure across all code submissions.

Actionable Tips:

• Write PR descriptions that explain why changes are needed, not just what changed. Provide the necessary context and motivation behind the modifications.
• Structure commits to tell a story (setup, implementation, tests, documentation). This logical flow makes it easier to follow the progression of changes.
• Include screenshots or videos for UI changes. Visual aids can significantly enhance understanding, especially for user interface modifications.
• Link to related issues, specifications, or discussions. Connecting the code changes to the broader project context provides valuable background information.
• Add comments that highlight non-obvious decisions. Explain the reasoning behind complex logic or unconventional choices.
• Consider creating diagrams for complex interactions. Visual representations can clarify intricate relationships and data flows.

Why This Deserves Its Place in the List:

Review-friendly code organization is a fundamental aspect of effective code review. It elevates code review from a tedious chore to a collaborative process that improves code quality, reduces bugs, and fosters knowledge sharing. By prioritizing clear communication and thoughtful organization, developers can significantly enhance the effectiveness of code reviews and contribute to a more positive and productive development environment. This practice is essential for everyone from Data Scientists and System Administrators to Software and Mobile Engineers, and even Engineering Managers, Agile Coaches, and Product Managers who benefit from understanding the process. By understanding and implementing these principles, development teams can create a more efficient and collaborative code review process.

Top 8 Code Review Best Practices Comparison

| Practice | Implementation Complexity 🔄 | Resource Requirements ⚡ | Expected Outcomes 📊 | Ideal Use Cases 💡 | Key Advantages ⭐ | |-------------------------------|-----------------------------|------------------------|-------------------------------------------------|-------------------------------------------|------------------------------------------------------| | Pull Request Size Management | Medium | Low | Faster reviews, higher quality feedback | Feature/task-focused, incremental changes | Faster feedback, easier conflict resolution, better tracking | | Automated Code Quality Checks | High | Medium-High | Early detection of trivial issues, consistent style | CI/CD pipelines, large codebases | Reduces reviewer fatigue, consistent and objective evaluation | | Review Checklists | Low | Low | Consistent review quality, fewer oversights | Teams needing standardization | Ensures coverage, reduces cognitive load, onboarding aid | | Constructive Feedback Techniques | Medium | Low-Medium | Positive review culture, improved collaboration | Teams emphasizing psychological safety | Builds trust, fosters learning, reduces defensiveness | | Clear Review Expectations and SLAs | Medium | Medium | Predictable review timings, accountability | Fast-paced or distributed teams | Reduces bottlenecks, sets clear roles, improves flow | | Multi-Perspective Reviews | High | High | Thorough, diverse code scrutiny | Critical/complex code requiring varied expertise | Catches diverse issues, knowledge sharing, reduces bias | | Knowledge Sharing During Reviews | Medium | Medium | Accelerated team learning, documentation | Teams focused on mentoring and onboarding | Reduces knowledge silos, builds collective understanding | | Review-Friendly Code Organization | Medium | Medium | Easier, faster reviews, better documentation | All code authors aiming to streamline review| Reduces cognitive load, speeds process, respects reviewer time |

Boost Your Development Workflow with Pull Checklist

Mastering code review best practices is crucial for any development team striving for high-quality, reliable software. From managing pull request size and leveraging automated code quality checks to fostering constructive feedback and incorporating diverse perspectives, each practice discussed in this article contributes to a more robust and efficient development process. Remember, the key takeaways are to establish clear expectations, facilitate knowledge sharing, organize code for reviewability, and streamline the entire process. By consistently applying these code review best practices, teams can minimize bugs, improve code maintainability, and accelerate the delivery of valuable features. This translates to not only better software but also increased team productivity and collaboration across roles, from Data Scientists and DevOps Engineers to Product Managers and IT Analysts.

These best practices become even more powerful when combined with the right tools. By automating essential elements of your code review process, you free up valuable engineering time and reduce the potential for human error. Ready to take your code reviews to the next level? Explore Pull Checklist on the GitHub Marketplace (Pull Checklist) and discover how this powerful tool can help your team implement and maintain these code review best practices, ensuring consistent quality and streamlined workflows.