12 Best Practices for Better Code Reviews
Quality feedback is essential in virtually any creative endeavor – and we’d certainly count software programming as a creative endeavor.
That’s why establishing and optimizing a code review process is vital to the health of your overall software development lifecycle. Done right, code reviews are good for professional development, software quality, application security, and other aspects of your team’s overall growth and performance.
Leveraging the right code review tools, such as GitHub or automated linters, can further streamline the process and make it more efficient and impactful.
Code review proponents commonly cite a stat from the book Code Complete, by Steve McConnell, which says that comprehensive code inspections unearthed around 60% of defects, compared with 25-45% in standard checks.
In this article, we’ll unpack the keys to a strong code review process, with expert advice on doing it right.
Why Are Code Reviews Important?
In a sense, the importance of code reviews speaks for itself: the process is all about improving software quality, reliability, and business outcomes – while conversely reducing defecting, security issues, technical debt, and other potential problems.
But they can actually be part of a healthy organizational culture overall, according to Mike Stone, co-founder of The Gnar Company, a custom web and mobile development firm based in Boston.
Stone says his firm operates with a mantra of “engineers, but human” – in part to proactively counter some of the negative assumptions out there about developers’ ability to work well with others.
“It’s a nod both to our collaborative nature and our commitment to defying the dreaded “working with developers” stereotype,” Stone tells The CTO Club. “Our code review process is not an afterthought, nor a bonus task, but an integral part of our process and culture.”
Code reviews give the team a regular mechanism for communicating and collaborating with one another.
“As we review and celebrate each other’s code, we grow our sense of mutual responsibility and collective ownership over the work we do,” Stone says.“We also take pride in our continued dedication to a job well done."
Types of Code Reviews
Code review processes can – obvious statement alert! – look different across teams and organizations. But you can group many of them into two categories, which aren’t mutually exclusive.
- Formal Code Reviews: These are structured sessions where developers present their code changes to peers for review and comment. This type often involves detailed inspection, discussion, and documentation. Formal reviews are thorough but can be time-consuming and, if you don’t have a healthy culture in place, stressful. (A positive, blameless culture should mitigate that.)
- Tool-Assisted Reviews: Utilizing platforms like GitHub, GitLab, or Bitbucket, developers submit their pull requests for review. These tools facilitate inline commenting, automated checks, and version control, making the process more efficient and trackable. Compared with manual code reviews, tool-assisted reviews are typically faster and can be done more frequently, without pulling people away from other priorities. The growth of AI coding assistants will expand this category even more.
Tool-assisted reviews are also sometimes grouped under a broader umbrella of “lightweight” code reviews, or code-review processes that are less formal and often less time-consuming. Other examples of lightweight code review processes include pair programming, a model in which two devs work in tandem – one writing code, and the other reviewing it while they work.
Deciding on which type(s) of code reviews are best for your team is an essential early step.
10 Top Code Review Tools!
Here's my pick of the 10 best software from the 10 tools reviewed.
Key Players in Code Reviews
Another essential early step: identifying the right team members for the right roles in your code review process. The specific people will vary somewhat depending on the makeup of your team, but obviously developers – or anyone who writes code in your org – should be on the list. (Duh.) Other possibilities include roles like Site Reliability Engineers, DevOps engineers, security engineers, and anyone else with a vested interest in positive, blameless code reviews aimed at improving software quality.
No matter the role or person, code review participants generally fall into one of two categories: authors (the people writing the code) and reviewers (the people reviewing that code). We’ll share some advice for both roles a bit later in the article.
12 Best Practices for More Productive Code Reviews (& for Solving Challenges)
“Overall, code reviews help create a culture of continuous improvement and shared responsibility for code quality, which ultimately leads to more reliable and maintainable software,” says Derek Ashmore, Application Transformation Principal at the cloud consulting firm Asperitas.
There’s no guarantee of that outcome, of course – just telling one developer to review another developer’s code isn’t likely to produce optimal results. Common challenges include inconsistent or sparse feedback, personal biases, and competing priorities or time constraints that make code reviews feel like a burden.
To set yourself up for success, Ashmore and Stone suggest the following tips and best practices for implementing or improving your code review process.
1. Focus on the Code, Not the Person
“Always review the code, not the developer,” Ashmore says.
Strive to make feedback objective, respectful, and constructive – petty or personal criticisms can undermine the whole process. It’s not a “gotcha” game.
2. Set Clear Guidelines and Standards
It’s almost possible to have positive, productive code reviews when participants don’t know the goals or standards that they’re working towards. Leadership should set the right tone early and recalibrate as needed. Clear communication is a must.
“Ensure all team members know the coding standards and guidelines,” Ashmore says. “This includes naming conventions, formatting, and architectural best practices. Reviewers should be aligned on these to provide consistent feedback.”
3. Limit the Scope of Each Review
You’ve probably heard the phrase “don’t try to boil the ocean” and its variants. The principle applies here: if you ask people to do too much in a single review, it can lead to mistakes – and also resistance from people who already have lots of other responsibilities on their plates.
“Reviewing large pull requests can be overwhelming and prone to oversights,” Ashmore says. “Smaller, focused reviews are easier to manage and more effective. Aim to review manageable chunks of code, typically no more than 200-400 lines.”
4. Give Feedback on Structure and Logic First
Ashmore also recommends addressing structural and logical issues before moving on to relatively minor details like style and formatting. "This ensures that the foundational aspects of the code are solid before you dive into nitpicks,” he says.
5. Use Automation for Routine Checks
As in many other repetitive IT processes, automation can be a significant time-saver. This is one way that tool-assisted reviews can actually augment (rather than replace) formal, human-led reviews.
“Automate checks for style, formatting, and other simple conventions using tools like linters or CI pipelines,” Ashmore says. “This saves reviewers time and lets them focus on more critical issues like code logic and structure.”
6. Encourage Descriptive Commit Messages
“Ask developers to write clear and descriptive commit messages,” Ashmore advises. “This provides context for each change, making the review process smoother and helping future team members understand the history of the code.”
Detail from authors is critical, especially if someone from outside the project is going to be reviewing. "Not only does it give reviewers full context—what’s changing and why—but it also allows them to learn from the author’s work,” says Stone. “For reviewers, detail plays an equally important role. It helps the author understand the purpose of a suggestion, whether it’s a minor nitpick or a critical issue that could break something.”
7. Ask Clarifying Questions
Encourage questions as a key mechanism for generating productive feedback. Among other reasons, a question gives the author-developer a chance to reflect and respond meaningfully – rather than getting defensive. And it gives reviewers the chance to better understand previous choices rather than making assumptions.
“Questions can lead to better understanding and allow the developer to explain their reasoning or consider alternative approaches,” Ashmore says.
Similarly, Stone recommends that reviewers avoid dogmatic beliefs or statements in their feedback. Unless a particular line of code is going to break something, treat feedback as suggestions rather than mandates.
“Instead of saying ‘do this’ or ‘do that,’ we stick to a more open, collaborative, brainstorming-style approach," Stone says. “[Try] ‘what do you think of this?’”
8. Look for Potential Issues, Not Just Bugs
Some code reviews focus narrowly on actual bugs or defects. That’s fine, but might be too limited in scope. Holistic code reviews can also look for things like edge cases, performance implications, and scalability issues. They can also be an opportunity to address technical debt – those trade-offs made previously to hit a deadline or other goal.
“Good code reviews go beyond just spotting bugs and involve thinking about how the code will behave in various scenarios," Ashmore says.
9. Encourage Test Coverage
“Ensure that new features or changes include appropriate tests,” Ashmore says.“Encourage adding unit tests and integration tests as relevant to help catch bugs and document expected behaviors.”
10. Be Timely and Responsive
Ashmore also recommends time-boxing your reviews and setting deadlines for feedback, such as 24 hours or another reasonable timeframe:“Quick feedback helps maintain momentum. Additionally, respond to any questions or clarifications from the developer promptly.”
11. Balance Praise and Critique
Both Ashmore and Stone emphasize the value of positive feedback and celebrating wins – not simply criticizing or pointing out defects. Doing so is key to continuous improvement and reinforcing the best practices and positive outcomes.
“Don’t forget to recognize good work,” Ashmore says.
Doing so is key to continuous improvement and reinforcing the best practices and positive outcomes.
“Celebrating each other’s moments of brilliance, no matter how big or small, is validating, motivating, and inspiring,” Stone says. “Positive comments like ‘TIL’ (today I learned…) or ‘This is sweet! How does it work?’ reinforce positive behavior, bring smiles to our faces, and reiterate the purpose behind the review process.”
12. Document and Share Learnings
Documentation is good, especially when it helps identify and solve recurring issues, or helps bring new team members up to speed quickly.
“When recurring issues or patterns emerge, document them for future reference,” Ashmore says. "Consider creating a shared repository of review checklists, guidelines, and common issues to help streamline future reviews.”
While comments are suggestions and not rules, it’s still important for authors to close the loop by acknowledging reviewer comments. Stone adds, "This ensures all feedback has been seen, addressed, and considered. It also fosters further conversation and knowledge transfer, which are essential to continuous improvement.”
Tools for Code Reviews
No matter how you develop and implement code reviews in your org, there are many tools that can help – whether for automation, version history, documentation, or other purposes. In fact, there are so many options, finding the right ones can seem daunting.
Fear not, The CTO Club’s expert reviewers have you covered. Here are four lists to get you started:
- 20 Best Code Review Tools For Developers
- 20 Best Code Analysis Tools
- The 23 Best Static Code Analysis Tools For Java
- 24 Best Source Code Management Software To Boost Your Code Game
Need expert help selecting the right tool?
With one-on-one help, we guide you to your top software options. Narrow down your software search & make a confident choice.
Final Thoughts
Done well, regular code reviews are a vital part of software cultures built on collaboration and continuous improvement.
"Code reviews are not just a mechanism for improving code quality; they are an opportunity to build a collaborative, growth-oriented culture. By embracing detailed, thoughtful feedback and celebrating successes, teams can transform code reviews into a cornerstone of innovation and teamwork," posits Stone.
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