10 Best Practices for Code Reviews

Code review best practices help the team review pull requests with more clarity, less noise, and more impact on code quality. The idea is not to turn review into a hunt for mistakes, but to create a process that helps the author, protects the codebase, and keeps the development flow healthy.

In this guide, you will see simple practices to improve your reviews: understand the PR context, give objective feedback, avoid giant PRs, use checklists, review tests, automate what is repetitive, and focus on the points that really change the quality of the delivery.

Code review best practices in summary

Best practice	How to apply it
Understand the context	Read the PR description, the task, and the goal of the change before commenting.
Give objective feedback	Explain the problem, the impact, and a concrete suggestion.
Do not treat review as a hunt for mistakes	Recognize good decisions and use the review to share knowledge.
Review smaller PRs	Break large changes into smaller parts that are easier to validate.
Use a checklist	Standardize criteria for logic, tests, security, readability, and scope.
Review the tests	Check whether the tests cover the expected behavior, errors, and edge cases.
Automate the repetitive parts	Use linters, tests, static analysis, and AI to avoid predictable manual comments.
Prioritize what matters	Block bugs, risks, and logic problems; do not hold up the merge over small preferences.
Look at the whole picture	Evaluate impact, architecture, clarity, and whether the change solves the right problem.

Before asking for code review

A good code review starts before the first comment. The person opening the PR is also responsible for the quality of the review. The clearer the context is, the lower the chance that the reviewer will spend time trying to guess the intent behind the change.

Before asking for review:

• review your own diff;
• explain the goal of the PR;
• run basic tests and checks;
• separate unrelated changes;
• call out when the change is urgent, sensitive, or depends on external context.

You do not need to write a thesis in the PR description. But the reviewer needs to understand what changed, why it changed, and where they should pay more attention. Code review should not be a puzzle.

1. Understand the context before anything else

Before opening the pull request and starting the review, take a minute to understand the context of the change. Read the PR description, the associated task, previous comments, and any decision that explains the reason for that change.

This completely changes the quality of the feedback. Without context, the reviewer tends to comment on isolated details. With context, they can evaluate whether the solution solves the right problem, whether the scope makes sense, and whether there is any hidden risk.

If the PR has no description, ask for context before reviewing. A good comment can be simple:

Can you add a summary of the problem and the main points that changed? This helps review it more accurately.

2. Be objective and constructive with feedback

During a code review, focus on the points that really make a difference: business logic, clarity, security, performance, tests, and alignment with the team’s standards.

When pointing out a problem, explain the reason. Well-founded comments help the author understand the decision and reduce back-and-forth in the PR.

Instead of commenting:

Use another function here.

Prefer something like:

It would be better to use map here because we want to return a new list without changing the original structure. This makes the intent clearer and avoids side effects.

A good comment answers three things:

• what the problem is;
• why it matters;
• what path you suggest.

3. Code review is not a hunt for mistakes

Code review is not only for pointing out problems. It is also an opportunity to reinforce good decisions, share knowledge, and align team standards.

If you saw a simple solution to an annoying problem, say it. If the author improved the readability of an old part of the code, recognize it. This type of comment is not “too cute”; it helps create a culture where review is not seen as an attack.

Balance matters. A review that only shows up to criticize becomes a source of friction. A review that combines important corrections with sincere recognition tends to improve team collaboration.

4. Do not drown in giant pull requests

Large PRs are harder to review, more tiring, and more likely to hide problems. When a change has many files, several goals, and hundreds of lines, the reviewer starts to lose context.

Whenever possible, encourage smaller and more frequent PRs. They reduce waiting time, make review easier, and make feedback more precise.

But the problem is not only size. Coherence also matters.

A small PR can still be bad if it mixes a feature, refactor, visual adjustment, and bug fix in the same package. When changes with different goals come together, the reviewer needs to switch context all the time.

A practical rule: if you need to explain the PR with “and also,” maybe it should be split.

5. Use checklists so nothing important gets missed

A code review checklist helps the team keep consistency. It reduces forgetfulness and prevents each person from reviewing with completely different criteria.

The checklist does not need to be huge. In practice, it should remind the reviewer of the points that matter most to the team.

Example:

• Does the implementation solve the described problem?
• Does the PR contain only related changes?
• Is the code readable for someone who did not participate in the implementation?
• Does the main logic have tests?
• Are error scenarios covered?
• Does the change create a security risk?
• Is there any performance impact?
• Does the code follow the team’s standards?
• Is there unnecessary duplication or complexity?
• Does the documentation need to be updated?

6. Review the tests before the implementation

A simple way to improve code review is to start with the tests. They show which scenarios the author considered important and help you understand the intent of the change before going into the implementation details.

When reviewing tests, check whether they cover the main behavior, error cases, important boundaries, and risks introduced by the PR. It is also worth checking whether the test names make the expected behavior clear.

If the tests are hard to understand, too fragile, or too coupled to the implementation, that is also code review feedback. A test is not just proof that the code works now. It is living documentation of the behavior the team wants to preserve.

Useful questions for reviewing tests:

• Does the test cover the behavior the PR promises to deliver?
• Are there relevant error or edge scenarios?
• Does the test fail if the business rule breaks?
• Does the test name explain the expected behavior?
• Is the test validating behavior or too much internal detail?
• Did any existing test need to be updated? Why?

7. Automate what you can

Automating code review does not mean removing people from the process. It means removing from the human reviewer what is repetitive.

Linters, formatters, automated tests, static analysis, and AI tools for code review help avoid manual comments about formatting, simple standards, and predictable problems. This frees the reviewer to focus on what requires judgment: business logic, architecture, security, clarity, and the impact of the change.

Kody, Kodus’s open-source code review agent, reviews pull requests automatically and comments on relevant points in the PR flow. It can apply team rules, consider repository context, and help keep feedback more consistent without turning review into an endless list of manual comments.

Here is an example of a reviewed PR:

Automation should complement human review, not replace the team’s responsibility.

8. Be patient and dedicate time to review

Rushing is the enemy of a good code review. If you review in the middle of another task, while answering notifications and without real attention, the chance of missing something important increases.

Try to reserve specific blocks for reviewing PRs. It does not need to be a heavy ritual. It can be a short time in the early afternoon or a few fixed moments throughout the day. The important thing is to avoid reviewing everything on autopilot or letting PRs pile up for days.

You also need to take care of the context. If the PR requires attention, open the task, read the description, understand the tests, and review calmly. Reviewing in a rush just to “unblock” the merge can become expensive later.

9. Prioritize important problems

Not every comment has the same weight. Bugs, security issues, logic problems, contract breaks, and production risks should have priority.

Then come improvements in design, readability, performance, and maintenance. Last come the nits: small names, style, personal preferences, or details that could be solved by an automatic tool.

A simple way to organize comments is to make the level of importance clear:

• blocking: needs to be resolved before merge;
• suggestion: recommended improvement;
• nit: small detail, should not block;
• question: a question to better understand the decision.

This prevents the author from treating every comment as urgent and helps the team keep the flow moving without giving up quality.

10. Focus on the whole picture, not just the details

It is easy to fall into line-by-line review and forget the change as a whole. But a good code review also needs to evaluate impact.

Ask:

• Does this change solve the right problem?
• Does the design make sense for the project?
• Is there a simpler solution?
• Does the change increase complexity unnecessarily?
• Could any part of the system be affected?
• Will the code be easy to maintain a few months from now?

Details matter, but context does too. A well-written function can be part of a bad solution. In the same way, a small adjustment can break an important contract if no one looks at the overall impact.

How to choose reviewers for a PR

Choosing reviewers is not about tagging everyone who knows the project. The more required people there are in a review, the higher the chance that no one feels truly responsible.

In most cases, one or two active reviewers are enough. Call someone with context on the changed area when the change is sensitive, and include less experienced people when the goal is also to share knowledge.

If someone only needs to be aware of the change, prefer notifying them without turning that person into a blocker for the PR.

Good rules:

• choose reviewers who know the changed area;
• avoid adding too many reviewers “just to be safe”;
• explain what you expect from each reviewer;
• include juniors when the review is also a learning opportunity;
• call specialists when there is a security, performance, or architecture risk.

Simple template for code review comments

A good comment does not need to be long. It needs to be clear.

Use this format:

Problem: what can go wrong here?
Impact: why does this matter?
Suggestion: what change do you recommend?

Example:

Problem: this validation happens after the external call.
Impact: we may make an unnecessary request and expose an error to the user.
Suggestion: validate the data before calling the service.

This format helps mainly when the comment is blocking. For questions or lighter suggestions, you can be simpler. The important thing is to avoid vague feedback, such as “improve this” or “I don’t like it.”

When to move out of the PR comment

Not every discussion needs to continue in the PR comment. If the conversation becomes a long debate, involves a sensitive decision, or is getting ambiguous, call the person for a quick conversation.

Then, record the decision in the PR itself.

This keeps the history without turning the review into an endless thread. The problem is not talking outside the PR. The problem is making a decision outside the PR and leaving no trace for the rest of the team.

Quick code review checklist

Before approving a PR, mentally review:

• Does the PR solve the described problem?
• Is the scope clear?
• Are there unrelated changes?
• Is the main logic correct?
• Do the tests cover the relevant scenarios?
• Is the code readable?
• Is there any security risk?
• Is there any performance impact?
• Does the code follow the team’s standards?
• Does the solution increase complexity?
• Does any important decision need to be documented?
• Are the comments made in the review clear and actionable?

Code review is collaboration and learning

A good code review goes far beyond fixing problems in the code. It helps the team learn, share context, maintain standards, and protect the quality of the codebase.

The goal is not to approve PRs quickly at any cost, nor to turn every review into a dispute of opinions. The goal is to improve the change, help the person who wrote the code, and keep development flowing.

When the team combines smaller PRs, clear context, objective feedback, automation, and good priority criteria, code review stops being a bottleneck and becomes a real engineering practice.