13 Google-Inspired Code Review Standards to Boost Software Quality

In this article we briefly introduce 13 code review standards inspired by Google, aiming to greatly improve software quality while keeping developers happy.

Code review is a development step where one or more developers examine another developer's code to ensure:

The code has no errors, bugs, or issues.

The code follows quality and style guidelines.

The code fulfills all intended functionality.

After merging, the codebase remains functional and improves.

These reasons make code review a crucial part of software development. Reviewers act as gatekeepers, deciding whether code can become part of the repository and be deployed to production.

At Google, “the primary purpose of code review is to ensure that the overall health of the codebase continuously improves.” — Google Engineering Practices

The following points should be kept in mind when reviewing code.

1. Changes should improve the overall system health

Every pull request should make the system better, even if the improvement is small.

2. Review quickly and give constructive feedback

Do not delay merging. If the code improves the system, deliver it promptly. Aim to respond to a pull request within one workday and complete multiple review rounds in a day if possible.

3. Use the review to educate and inspire

Share knowledge and experience during the review.

4. Follow established standards

Style guides, programming standards, and documentation are the ultimate authority. Consistency in tabs vs. spaces, naming conventions, etc., should be enforced.

5. Resolve review conflicts collaboratively

Follow style guides and seek advice from knowledgeable teammates when conflicts arise.

6. Demonstrate UI changes when relevant

If a change affects the UI, provide a demo or automated UI tests to verify the expected appearance.

7. Ensure all required tests are present

Pull requests should include unit, integration, and end‑to‑end tests unless an emergency fix is needed; in that case, create a ticket to add tests later.

8. Do not interrupt focused work

Perform reviews during breaks so as not to disrupt developers’ flow.

9. Review all code, make no assumptions

Examine every line and understand its purpose; ask the author for clarification if needed.

10. Keep a big‑picture view

Consider the impact of changes on the whole file and codebase, not just the few added lines.

11. Recognize and encourage good work

Praise outstanding changes to motivate authors.

12. Be respectful, clear, and friendly

Provide polite, focused feedback on the code, not the person.

13. Explain review comments with appropriate detail

When suggesting alternatives, explain the reasoning and give examples, balancing guidance with allowing the author to implement the solution.