Code Reviews: Best Practices for Impactful Code Reviews

Code review is a process in software development where the source code is systematically examined by one or more colleagues before it becomes part of the main codebase. This is typically done in the context of a pull request (in Git), where a developer asks peers to review their changes to a codebase before it is merged into the main branch.

Why Code Review?

1. Improving Code Quality: Code reviews help catch bugs and errors early in the development process. Reviewers can spot issues that the original author might have missed, leading to cleaner, more reliable code.
2. Ensuring Code Consistency: They help maintain a consistent coding style across the team, which is crucial for readability and maintainability. This includes coding standards and best practices.
3. Knowledge Sharing: Through code reviews, knowledge is shared across the team. 
4. Mentoring Opportunity: For less experienced developers, code reviews are an excellent learning tool. They receive direct feedback on their coding style and practices, helping them to improve their skills.
5. Code Ownership: They promote a sense of collective code ownership. When the whole team is involved in reviewing code, everyone feels responsible for the codebase’s quality and integrity.

Do’s:

1. Understand the Purpose of the Code: Before diving into a review, take time to grasp what the code change is meant to achieve. This could involve looking at the task description to get context.
2. Encourage Smaller, Incremental Changes: Smaller code changes are easier to understand and review. Encourage your team to make frequent, but smaller, commits and pull requests.
3. Automate Routine Checks: Use automated tools to perform basic checks, such as code formatting and style guidelines. This frees up time during code reviews to focus on more complex issues.
4. Provide Constructive and Detailed Feedback: When reviewing code, offer clear and actionable feedback. Suggest ways to improve the code, and explain why certain changes might be beneficial.
5. Encouage a Collaborative Review Culture: Treat code reviews as a collaborative process. Encourage open discussions and be willing to consider different perspectives and solutions.

Don’ts:

1. Large Reviews: Large code changes can be overwhelming and difficult to review thoroughly. 
2. Do Not Skip the Review Process: Even for seemingly minor changes, the review process should not be bypassed. Small changes can have unexpected consequences.
3. Focus on Code, Not the Coder: Keep the review objective and focused on the code itself. Avoid personal comments, as they can be demotivating and unproductive.
4. Pay Attention to Automated Feedback: Do not disregard the results from automated checks and tools. These are in place to catch common errors and enforce standards.
5. Wait for Thorough Review Before Merging: Resist the urge to merge changes too quickly. Ensure that every pull request undergoes a thorough review and meets all necessary criteria before merging.

Suggestions:

1. Continuous Integration (CI) Tools: Implement CI tools for automated testing and error checking, reducing manual review workload.
2. Self-Review: Encourage developers to self-review their code before peer review.
3. Encourage Positive Feedback Practices: Build an environment where feedback is provided in a supportive and positive manner.
4. Reviewer Rotation System: Rotate the responsibility of code reviewing among team members to distribute knowledge and avoid reviewer burnout.

Code reviews makes the whole development process smoother and more effective.