Code Review

Code review is the process by which one or more developers check a colleague's source code before merging it with the main version of an application. During a review you look at readability, logic, security and compliance with agreed standards. For SMEs that have a ecommerce store, customer portal or custom application built, code review is the most important quality check. It prevents errors, security holes or technical faults from ending up in your system unnoticed.

How code review works in practice

A developer makes changes in a separate version of the code, called a branch. Once the work is done, the developer opens a pull request or merge request. Other team members review the code line by line, asking questions, making suggestions and highlighting potential problems. Only after the review is approved may the code be merged. This is often done through platforms such as GitHub, GitLab or Bitbucket. In an SME context with outside developers or a small in-house team, this is the time when you check that the work fits your requirements and future maintainability. A good review takes between 15 minutes and an hour, depending on the complexity of the change.

Why code review came about and why it matters now

Code review became popular as software teams grew larger and collaboration through version control systems such as Git became the norm. The idea is simple: four eyes see more than two. Mistakes overlooked by the original developer catch the eye of a colleague immediately. In the early days of software development, programmers often worked solo, but as applications became more complex and business-critical, the need for structured quality control increased. For SMBs, code review is now relevant because you often work with changing external parties. A thorough review gives you insight into what is being built and prevents you from depending on one person who is the only one who understands the code.

What code review brings to SMEs

Code review reduces the number of bugs that end up in production, improves security and makes your code easier to transfer to another developer. In practice, we see with SME customers that an ecommerce store without code review often suffers from small but irritating errors: wrong price calculations, slow loading times or forms that do not submit. A single thorough review prevents your customers from encountering these. In addition, a junior developer learns faster through feedback from a senior. If you're having a new website development or expanding an existing application, explicitly ask if code review is part of the process. At web development by Monkey Vision, peer review is a standard part of every project. This way you can be sure that code not only works, but is also understandable and secure. You can read more about the importance of structured development in the Google Developers documentation.

Code review fits into different phases of a development process. You can use it for new features, bug fixes, performance optimizations or cleaning up old code. Below you can read where SME companies apply code review most effectively and when it is better to skip it.

New functionalities for ecommerce stores and customer portals

If you have a new checkout flow, a product configurator or a link to your accounting system built, code review is essential. These functionalities directly touch your sales or business operations. A review verifies that the logic is correct, that the API integration is set up securely and that the code is scalable as your assortment grows. In practice, we find that outside agencies sometimes take shortcuts to deliver faster. A thorough review exposes this. An ecommerce store with 800 products that gets a new filter function deserves a review of at least 45 minutes. This prevents filters from loading slowly or certain products from not appearing in search results.

Bug fixes and hotfixes under time pressure

Even in emergency solutions, code review pays off. A hotfix implemented quickly without review often solves one problem but introduces another. Think of a pricing error in your ecommerce store that you want to correct quickly: without a review, you risk that the fix only works for one product category or that the VAT calculation is no longer correct. A shortened review of 10 to 15 minutes is sufficient here. Ask a colleague or second developer to check that the change has no side effects. In WordPress website maintenance, this is a standard step before a patch goes live. This keeps your site stable, even under pressure.

Refactoring and addressing technical debt

Refactoring means rewriting code without changing functionality. You do this to improve readability, increase performance or replace old dependencies. Code review is crucial here because refactoring is intended to simplify future maintenance. A review verifies that the new code is really better than the old and that no functionality is lost. For example, an SME with a five-year-old WordPress site may decide to rewrite custom plugins. Without a review, you run the risk that the new code will not perform as well or that certain edge cases will no longer work. A thorough review here takes 60 to 90 minutes, but saves weeks of debugging afterwards.

When code review is the right choice and when it is not

Code review is useful for any changes that impact users, security or business logic. It is less useful for minor textual changes, updating documentation or adjusting CSS styling without logic. If you're a sole proprietor and developing on your own, you can skip code review for experimental prototypes or internal tools that no one else is using. Once you work with a team, outside developers or an agency, code review is not optional. It protects your investment and keeps you from becoming dependent on one person. In quotes, always ask if review is included and who the reviewer is. An agency that doesn't do this by default poses higher risks.