Nowadays, most companies include Code Review requirements in their job descriptions. It seems that at some point, Code Review became a fundamental skill for many developers, and only by mastering this skill can we be considered capable of working in large companies.
But do we really need Code Review? I believe that most organizations have not deeply considered this question.
What problems can Code Review solve?
First, why do we need Code Review? What problems are we trying to solve? Many organizations start implementing Code Review because they have accumulated technical debt while rushing to meet business demands. As the team size grows, many issues become apparent:
- Impact Issues after Code Merging: When code for different features is merged, it can affect other functionalities written by other developers. This conflict not only increases debugging complexity but also slows down the overall project progress.
- Reinventing the Wheel: Without Code Review, different developers might implement similar functionalities independently, leading to resource waste and redundancy in the codebase.
- Frequent Code Bugs: Without timely Code Reviews, many potential bugs and logical errors may be overlooked, which can later surface in production, causing larger issues.
The root of these problems lies in the fact that when the team initially comes together to sprint on a task, everyone is united, and code issues are minimal. However, as tasks are broken down and assigned to individuals, team leaders may feel a loss of control and seek to regain it through tools. In reality, the emerging issues are not due to team capability but rather management problems. These issues will not improve simply through Code Review.
Code Review should be a team culture
Indeed, if Code Review is done well, we can address many issues proactively. However, executing Code Review effectively is not easy; it relies not on individual capabilities but on the collective responsibility of the entire team. In other words, Code Review should be a team culture. This means we need to view it from the team's perspective rather than just from the product or project viewpoint. Therefore, if your team is still in a chaotic phase and has not found a rhythm of collaboration, trust me, Code Review will not benefit you. You need to first get the team organized.
In the long run, effective Code Review brings numerous benefits to the team:
- Improved Code Quality: Code Review is an effective way to enhance code quality. By reviewing code, teams can promptly identify and fix errors, potential security vulnerabilities, and performance issues, thus improving overall code quality. Studies show that over 50% of bugs are discovered during the Code Review process.
- Collective Growth: Code Review promotes knowledge sharing among team members. By reviewing others' code, developers can learn different implementation methods and best practices, thereby enhancing their skills. This also helps team members gain a better understanding of the project as a whole, enhancing collaboration.
- Reduced Fixing Costs: The earlier a problem is detected during development, the lower the cost of fixing it. Code Review can identify potential issues before code is submitted for testing, avoiding the need for extensive modifications and refactoring later on, thus lowering maintenance costs.
How to conduct effective Code Review?
Assuming you already have a good team, you can start to establish a Code Review culture.
Before starting, the team needs to clarify its values and goals, including improving code quality, promoting knowledge sharing, and maintaining coding standards. Ensuring all team members reach a consensus on the necessity of Code Review is the first step to success.
- Establish Process Norms: Start by defining when and how Code Reviews should occur.
- Timing: Code Reviews should take place before code is submitted for testing. This means that after developers complete their code and self-testing, they should have it reviewed before submitting to the testing branch. This helps identify issues early, reducing subsequent fixing costs.
- Granularity Control: It is advisable to control the amount of code submitted at one time to avoid overwhelming reviews. Smaller submissions facilitate review and improve the efficiency and effectiveness of Code Review.
- Define Roles: This step is crucial and reflects team culture. Code Review should be a team activity, with different team members reviewing each other's code to foster a learning atmosphere.
Some team leaders may implement a system where senior developers review junior developers' code. However, this arrangement can be problematic:
- Senior developers may not necessarily be more capable than junior developers, leading to differing viewpoints during reviews, with senior developers potentially unwilling to concede.
- This can easily become a mechanism for leadership to scrutinize employee output, causing junior developers to hesitate in innovating and only write the safest code, fostering a "do less, make fewer mistakes" mindset.
- Establish Code Standards: If we are to review others' code, what are the standards? Some teams conduct Code Reviews without established coding guidelines, which only creates additional work. For example, if there are no naming conventions, what should reviewers look for?
- Regular Sharing and Feedback: Establishing a feedback mechanism is the only way for the team to progress. Everyone will have different thoughts after reviewing so much code. We need to create an environment conducive to sharing and discussion. Regular knowledge-sharing sessions should be held to discuss best practices and lessons learned during the review process. This not only facilitates knowledge flow but also evaluates the effectiveness of Code Review.
At the same time, we should document the results and feedback from Code Reviews, analyzing the efficiency and quality of reviews to continuously optimize the process.
Most teams do not need Code Review
For an excellent development team, Code Review is indeed a good team culture and activity. But does every team need Code Review?
I believe that the vast majority of teams in the market do not need Code Review. This is because the cost of establishing a culture often exceeds the cost of solving most technical problems. Typically, when people think a team needs Code Review, they are often facing technical management issues. The focus should be on management-level solutions. Consider the following questions:
- Can the team communicate and collaborate effectively? Information asymmetry can lead to misunderstandings and inefficiency.
- Does the team have comprehensive development standards and consensus?
- How is the morale? Is everyone placed in suitable positions?
By addressing these issues, you will find that other problems will also resolve themselves.
In summary, while Code Review as a team activity and culture has significant benefits for improving code quality, promoting knowledge sharing, and reducing fixing costs, not every team needs to implement it. For some efficient teams, management and communication issues may be the real challenges, rather than the Code Review process itself.