Every software product, whether a website or mobile app, relies on code. The more consistent and organized this code is, the easier it will be to maintain and update, especially when modifications are necessary.

Quality code is defined by several key factors: ease of understanding, flexibility for updates, and clarity. However, despite the importance of writing quality code, developers often work under tight deadlines, and even experienced programmers sometimes produce suboptimal code. To ensure the code meets high standards, a code review process is often implemented.

A Code Review is a process where other developers assess a particular engineer's code to ensure it complies with standards, identifies errors, checks the coding style, and confirms that the code meets the project's objectives.

In this article, we will explain the code review process, its advantages and disadvantages, and share some of the best practices for conducting effective code reviews.

The Code Review Process: A Step-by-Step Guide

The goal of a code review is to ensure that changes made by developers are thoroughly checked by the rest of the team before being merged into the main code repository. The process typically follows these steps:

Code Submission

The developer adds new features to the code and requests the team to review these changes.

Code Review

Reviewers examine the code, leaving comments. It’s important to focus not just on bugs but also on identifying architectural flaws or instances of poor coding style (e.g., hard-to-understand or poorly formatted code).

Addressing Comments

The developer addresses comments and suggestions. If there is disagreement about any feedback, developers are encouraged to present a strong case for their point of view. If no convincing argument is made, the necessary changes are implemented.

Repetition

The process is repeated whenever new changes are introduced.

Who Conducts Code Reviews?

Typically, senior developers conduct code reviews for their junior colleagues, while middle-level developers review the code of other middle-level developers. Senior developers or team leads typically review the work of other senior developers. In larger companies, dedicated personnel may be assigned to handle code reviews and enforce coding standards.

In smaller teams, the lead developer often oversees the review process, ensuring the project is on track and maintaining code quality.

The Benefits of Code Review

A well-executed code review offers numerous advantages:

Error Detection: Identify bugs early that could cause major issues later.

Consistency: Ensure that the code adheres to team standards and practices.

Improved Code Architecture: Ensure the code's structure and design are optimal.

Code Quality: Enhance the overall quality of the codebase.

Skill Development: Code reviews offer opportunities for professional growth, especially for junior developers.

Team Collaboration: Foster better decision-making and consistency across the team.

Furthermore, code review reduces the "bus factor," meaning that if a developer leaves or is unavailable, the code will be easier for others to understand and maintain.

Disadvantages of Code Review

Despite the benefits, there are some downsides to the code review process:

Time Consumption: The process can take time, especially if many comments need to be addressed, leading to delays.

Increased Costs: The review process requires developers' time, which can add to the overall cost of the project.

When Code Review Is Not Necessary

While code reviews provide clear advantages, there are certain situations where they may not be required:

Prototypes and MVPs: For products meant to test ideas or gather feedback, code reviews may not be necessary, as the focus is often on speed rather than long-term code quality.

One-Off Projects: If the project is simple, and no future updates are planned, skipping code reviews could save time.

10 Best Practices for Effective Code Reviews

To ensure the code review process is as efficient and productive as possible, here are 10 best practices to follow:

Limit the Size of Code Reviews: Review no more than 400 lines of code per hour to maintain focus.

Time Management: Don't review for more than 60-90 minutes at a time to avoid diminishing attention.

Set a Consistent Schedule: Plan regular code review sessions at set times.

Automate Simple Checks: Use tools to automatically detect routine issues and common mistakes.

Track Metrics: Use metrics like inspection rate, defect rate, and defect density to improve the review process over time.

Maintain a Constructive Approach: Always provide feedback in a positive and helpful manner.

Involve Multiple Reviewers: Having more than one reviewer helps identify more issues and improves code quality.

Separate Style from Logic: Discuss code style separately from the review of the code itself.

Establish Standards: Clearly document and communicate code review guidelines to maintain consistency.

Suggest Improvements: Offer suggestions on how to simplify or optimize the code.

By following these best practices, the code review process can be made more efficient, enjoyable, and beneficial for all team members.

Final Thoughts

Code review is a vital practice in software development. When done properly, it significantly improves code quality and fosters team collaboration. However, it’s essential to have clear goals and expectations to avoid unnecessary distractions and ensure the process is effective. By adhering to the best practices outlined above, you can ensure a smoother, more productive code review experience for everyone involved.