3 GitHub Review Features That Cut Our Review Time in Half

GitHub reviews are the backbone of modern code quality practices, yet many teams barely scratch the surface of what's possible. While everyone uses basic PR comments and approvals, GitHub includes powerful features for enforcing quality gates, distributing review work, and streamlining collaboration that most teams never configure.

If your coding reviews feel slow or inconsistent, the issue is usually workflow design, not developer effort. The fixes are often simpler than adding a new tool.

This guide walks through GitHub's native code review features—from CODEOWNERS to branch protection rules—showing you how to optimize your review workflow without adding new tools to your stack.

GitHub Review Features Most Teams Underuse

Suggested Changes: One-Click Fixes

When reviewing pull requests, instead of writing "change X to Y" in a comment, use GitHub's suggested changes feature to propose the exact code modification. Reviewers write the fix, authors apply it with one click.

How to use suggested changes:

1. In a PR review comment, click the "Add a suggestion" button (± icon)
2. GitHub pre-fills a code block with the original line(s)
3. Modify the code to show what you recommend
4. The PR author sees a "Commit suggestion" button—one click applies your change

Best practices:

• Multi-line suggestions: Select multiple lines before clicking "Add a suggestion" to propose larger changes
• Batch commits: Authors can queue multiple suggestions and commit them all at once instead of creating separate commits
• Style fixes: Perfect for formatting, typos, or small refactorings that don't need explanation
• Add context: Include a comment above the suggestion explaining why you're recommending the change

Suggested changes reduce review round-trips. Instead of "fix the typo" followed by waiting for the author to make the change, the reviewer provides the fix directly.

Review Comments vs Review Requests

GitHub has three distinct review actions, but many teams only use "Comment" by default:

• Comment: General feedback without approving or blocking. Use for questions, suggestions, or non-blocking observations.
• Approve: Explicitly approves changes. Required if branch protection requires approvals.
• Request Changes: Blocks merging (if branch protection enforces it). Use for issues that must be fixed before merge.

Many reviewers leave multiple comments but never actually approve or request changes, leaving the PR author uncertain whether they can merge. Establish team norms: every review should end with an explicit approve or request changes decision.

Re-Request Review After Updates

When an author addresses review feedback, GitHub provides a "Re-request review" button (circular arrow icon next to the reviewer's name). This notifies the reviewer that their feedback has been addressed and the PR is ready for another look.

Without re-requesting, reviewers don't get notifications about updates, leading to PRs that sit "done" but unmerged because reviewers don't realize the author addressed their comments.

Team process tip: Make it a norm that authors always re-request review after making changes, rather than just commenting "Done."

Draft Pull Requests

Mark PRs as "Draft" when they're not ready for full review. Draft PRs:

• Can't be merged (even by accident)
• Signal to reviewers "not ready yet, don't spend time on this"
• Allow early feedback on direction without formal review
• Keep CI running to catch issues early

Use drafts when you want CI feedback or architectural input before the code is complete. When ready, click "Ready for review" to signal reviewers should look at it.

Setting Up CODEOWNERS Effectively

What CODEOWNERS Does

The CODEOWNERS file automatically requests reviews from specific people or teams when a PR touches certain files or directories. This ensures the right experts see changes to their areas of responsibility.

Basic CODEOWNERS Syntax

Create a file at .github/CODEOWNERS in your repository:

# Default owner for everything in the repo
* @your-org/engineering-team

# Frontend code requires frontend team review
/src/components/ @your-org/frontend-team
/src/pages/ @your-org/frontend-team
*.tsx @alice @bob

# Backend code requires backend team review
/api/ @your-org/backend-team
/services/ @your-org/backend-team
*.py @charlie @diana

# Infrastructure requires DevOps review
/infrastructure/ @your-org/devops-team
/docker-compose.yml @your-org/devops-team
/Dockerfile @evan

# Database migrations require DBA review
/migrations/ @your-org/database-team @frank

Pattern Matching Rules

CODEOWNERS uses gitignore-style patterns:

• * matches any files in the directory
• ** matches zero or more directories
• /path/ matches the directory and all subdirectories
• Last matching pattern wins (more specific rules override general ones)

Teams vs Individuals

Reference GitHub teams with @org-name/team-name or individuals with @username. Teams are better for most cases:

• Load distribution: GitHub rotates review requests among team members instead of pinging everyone
• Easy updates: Add/remove team members in GitHub settings without updating CODEOWNERS
• Clear ownership: Team names are more descriptive than individual usernames

Advanced CODEOWNERS Patterns

Multiple owners (all required):

# Security-sensitive files require both security team AND relevant domain team
/api/auth/ @your-org/security-team @your-org/backend-team
/src/payments/ @your-org/security-team @your-org/frontend-team

File extension matching:

# All TypeScript files
*.ts @your-org/typescript-experts
*.tsx @your-org/typescript-experts

# All Python files
*.py @your-org/python-team

# All YAML config files
*.yml @your-org/devops-team
*.yaml @your-org/devops-team

Specific files:

# Critical config files require architect review
/package.json @your-org/architects
/pyproject.toml @your-org/architects
/.github/workflows/ @your-org/devops-team

CODEOWNERS Anti-Patterns to Avoid

1. Too granular: Don't assign different owners to every single file. This creates fragmented reviews and slows PRs.

2. Single points of failure: Avoid assigning individuals as sole owners. Use teams or list multiple people.

3. Too many required owners: If every PR requires 5+ different teams to review, PRs will stall.

4. Stale ownership: When team members leave, update CODEOWNERS immediately.

Suggested Changes and Batch Reviews

The Power of Batch Suggestions

GitHub allows PR authors to queue multiple suggested changes and commit them all at once, rather than creating separate commits for each suggestion. This is especially valuable when a reviewer provides 5-10 small fixes across different files.

How to batch suggestions as a PR author:

1. A reviewer leaves multiple suggestions across your PR
2. Instead of clicking "Commit suggestion" on each one, click "Add suggestion to batch"
3. Review all queued suggestions at once
4. Click "Commit suggestions" (plural) at the top to apply them all in a single commit

This keeps PR history cleaner (one "Address review feedback" commit instead of six "Fix typo" commits) and saves time for both author and reviewer.

Suggesting Code Blocks

Suggested changes aren't limited to single lines. Select multiple lines in the PR diff before clicking "Add a suggestion" to propose larger refactorings:

// Instead of commenting "Extract this to a function," show the refactoring:

// Suggestion: Extract validation logic
function validateUserInput(input) {
  if (!input.email) throw new Error('Email required');
  if (!input.name) throw new Error('Name required');
  return true;
}

// Then call it
if (validateUserInput(req.body)) {
  // ... rest of handler
}

When reviewers provide working code, authors can apply it directly rather than interpreting instructions.

Review Comments vs Suggestions: When to Use Each

Use suggestions for:

• Typos, formatting, naming
• Small logic fixes
• Import reordering
• Simple refactorings

Use comments for:

• Architectural questions
• Complex changes requiring explanation
• When you want discussion, not just a fix
• Security or design concerns

Review Assignment Strategies

Automatic Assignment with CODEOWNERS

When CODEOWNERS is configured, GitHub automatically requests reviews from the designated owners when a PR is opened. This removes the manual step of figuring out who should review.

To enable automatic assignment:

1. Go to Settings → Branches → Branch protection rules
2. Select your protected branch (usually main or master)
3. Enable "Require a pull request before merging"
4. Enable "Require review from Code Owners"

Now, when anyone opens a PR that touches files listed in CODEOWNERS, the specified reviewers are automatically added.

Team-Based Review Rotation

When you assign a GitHub team as a CODEOWNER, GitHub's default behavior is to notify all team members. To distribute load better, configure team review assignment:

1. Go to your organization → Teams → Select the team
2. Click "Settings"
3. Under "Code review assignment," click "Enable auto assignment"
4. Choose your assignment algorithm:
   • Round robin: Rotate through team members in order
   • Load balance: Assign to the person with fewest pending reviews
5. Set how many team members to assign (1-2 is typical)

This prevents the "notify everyone, everyone ignores it" problem. One or two specific team members get assigned and are accountable for reviewing.

Review Fallback Options

Configure team settings to handle unavailability:

• Skip members on vacation: GitHub can automatically skip team members who have busy status set
• Notify team if reviewers don't respond: Escalate to the full team if assigned reviewers don't respond within a threshold

Manual Assignment Best Practices

For PRs that don't match CODEOWNERS or need specific expertise:

• Assign reviewers when opening the PR, not hours later when you remember
• Check reviewer workload: Before assigning, glance at how many other PRs they're reviewing
• Add context in the PR description: "Requesting review from @alice because she worked on this feature last quarter"
• Use the right number: 1-2 reviewers for most PRs, 3+ for critical changes only

For strategies on balancing review load across your team, see our Review Load Balancing Guide.

Branch Protection Rules That Work

Essential Protection Rules

Branch protection rules enforce quality gates before code reaches your main branch. Here's a progression from minimal to comprehensive protection:

This prevents direct commits to main and ensures PRs pass CI and get at least one approval.

This adds requirement for CODEOWNERS approval, dismisses outdated approvals when code changes, and requires all review threads to be resolved.

Status Checks: What to Require

Recommended status checks to require before merging:

• Automated tests: Unit, integration, and end-to-end tests must pass
• Code quality: Linters, formatters, type checkers
• Security scans: Dependency vulnerability checks, SAST tools
• Build verification: Ensure code actually compiles/builds

Don't require slow, flaky, or non-critical checks. Every required check adds delay and frustration when it fails intermittently.

Handling Dismissal of Stale Reviews

"Dismiss stale pull request approvals when new commits are pushed" is one of the most important settings. Here's why:

Without this setting:

1. Reviewer approves PR at 2pm
2. Author makes significant changes at 3pm (new commits)
3. PR still shows as "approved" even though reviewer hasn't seen the new code
4. PR can be merged without re-review

With this setting:

1. Reviewer approves PR at 2pm
2. Author makes changes at 3pm
3. Approval is automatically dismissed
4. Author must re-request review of the new changes

This prevents the common problem of PRs being approved, then substantively changed, then merged without re-review.

Require Conversation Resolution

Enabling "Require conversation resolution before merging" ensures authors explicitly address all review comments. Reviewers mark threads as "Resolved" when satisfied.

This prevents PRs from being merged with open questions or unaddressed feedback.

Measuring Review Effectiveness

Key Metrics to Track

GitHub gives you the tools, but are they working? Track these metrics to measure the effectiveness of your review process:

1. Review Coverage Rate

What percentage of merged PRs received at least one substantive review? Target: 95%+.

Low coverage indicates branch protection rules aren't enforced or team culture tolerates merging without review.

2. Time to First Review

How long do PRs wait before someone starts reviewing? Target: under 4 business hours.

Long waits suggest reviewer overload, unclear ownership (CODEOWNERS not configured), or lack of review accountability.

3. Review Round Trips

How many request-changes → update → re-review cycles does a typical PR go through? Target: 1-2 rounds.

High round-trip counts suggest PRs are too large, lacking context, or code quality issues that should've been caught by CI/linting.

4. Review Load Distribution

Is review work spread evenly, or do 2-3 people handle most reviews? Target: no single reviewer handles more than 25% of team reviews.

Concentrated reviews create bottlenecks and burnout. See our Review Load Balancing Guide for strategies.

5. PR Cycle Time

Total time from PR opened to PR merged. Target: under 24 hours for small PRs, 2-3 days for larger ones.

Long cycle times compound delays across your entire team. See our guide to reducing PR cycle time.

Where to Find These Metrics

GitHub's built-in insights (limited):

• Repository → Insights → Contributors shows review counts
• Pull Requests tab shows open/closed counts but no timing metrics
• No historical trends or team-level aggregation

GitHub API + custom scripts:

You can query GitHub's API for detailed PR data, but this requires scripting:

# Example GraphQL query for PR review timing
query {
  repository(owner: "your-org", name: "your-repo") {
    pullRequests(first: 100, states: MERGED) {
      nodes {
        createdAt
        mergedAt
        reviews(first: 10) {
          nodes {
            createdAt
            author { login }
            state
          }
        }
      }
    }
  }
}

Analytics platforms:

Tools like CodePulse automatically collect and visualize these metrics without custom scripting. CodePulse tracks review coverage, time to first review, reviewer load distribution, and cycle time trends over time.

For a comprehensive comparison of code review analytics tools, see our Code Review Platforms Comparison Guide.

Setting Review SLAs

Service Level Agreements for reviews turn "get to it when you can" into team commitments:

• First response SLA: 4 business hours (same-day for morning PRs, next morning for afternoon PRs)
• Follow-up SLA: 2 business hours after author addresses feedback
• Small PR SLA: PRs under 100 lines should merge same day if approved

Make SLAs visible. Dashboard alerts for "PRs approaching SLA breach" create healthy accountability without micromanagement.

Continuous Improvement Loop

Review effectiveness isn't static. Establish a regular cadence:

• Weekly: Quick check of review metrics in team standup. "Are any PRs stuck? Is anyone overloaded?"
• Monthly: Review trends. Are metrics improving? Where are remaining bottlenecks?
• Quarterly: Retrospective on review culture. Update CODEOWNERS, adjust protection rules, refine SLAs.

What gets measured and discussed gets improved. Teams that regularly review their review process see continuous cycle time improvements.