Awesome Skills Code Review Skill Code Review Skill

Code Review Skill

Transform code reviews from gatekeeping to knowledge sharing through constructive feedback, systematic analysis, and collaborative improvement.

When to Use This Skill

• Reviewing pull requests and code changes
• Establishing code review standards for teams
• Mentoring junior developers through reviews
• Conducting architecture reviews
• Creating review checklists and guidelines
• Improving team collaboration
• Reducing code review cycle time
• Maintaining code quality standards

Core Principles

1. The Review Mindset

Goals of Code Review:

• Catch bugs and edge cases
• Ensure code maintainability
• Share knowledge across team
• Enforce coding standards
• Improve design and architecture
• Build team culture

Not the Goals:

• Show off knowledge
• Nitpick formatting (use linters)
• Block progress unnecessarily
• Rewrite to your preference

2. Effective Feedback

Good Feedback is:

• Specific and actionable
• Educational, not judgmental
• Focused on the code, not the person
• Balanced (praise good work too)
• Prioritized (critical vs nice-to-have)

❌ Bad: "This is wrong."
✅ Good: "This could cause a race condition when multiple users
         access simultaneously. Consider using a mutex here."

❌ Bad: "Why didn't you use X pattern?"
✅ Good: "Have you considered the Repository pattern? It would
         make this easier to test. Here's an example: [link]"

❌ Bad: "Rename this variable."
✅ Good: "[nit] Consider `userCount` instead of `uc` for
         clarity. Not blocking if you prefer to keep it."

3. Review Scope

What to Review:

• Logic correctness and edge cases
• Security vulnerabilities
• Performance implications
• Test coverage and quality
• Error handling
• Documentation and comments
• API design and naming
• Architectural fit

What Not to Review Manually:

• Code formatting (use Prettier, Black, etc.)
• Import organization
• Linting violations
• Simple typos

Review Process

Phase 1: Context Gathering (2-3 minutes)

Before diving into code, understand:

1. Read PR description and linked issue
2. Check PR size (>400 lines? Ask to split)
3. Review CI/CD status (tests passing?)
4. Understand the business requirement
5. Note any relevant architectural decisions

For large diffs, pipe the diff through scripts/pr-analyzer.py (git diff main...HEAD | python scripts/pr-analyzer.py) to triage complexity and get a suggested review approach before reading.

Phase 2: High-Level Review (5-10 minutes)

1. Architecture & Design - Does the solution fit the problem?
   • For significant changes, consult Architecture Review Guide
   • Check: SOLID principles, coupling/cohesion, anti-patterns
2. Performance Assessment - Are there performance concerns?
   • For performance-critical code, consult Performance Review Guide
   • Check: Algorithm complexity, N+1 queries, memory usage
3. File Organization - Are new files in the right places?
4. Testing Strategy - Are there tests covering edge cases?

Phase 3: Line-by-Line Review (10-20 minutes)

For each file, check:

• Logic & Correctness - Edge cases, off-by-one, null checks, race conditions
• Security - Input validation, injection risks, XSS, sensitive data
• Performance - N+1 queries, unnecessary loops, memory leaks
• Maintainability - Clear names, single responsibility, comments
• Reuse - Before accepting new code, search for existing utilities/helpers that could replace it. Check adjacent files and shared modules for similar patterns. See Universal Quality Guide for anti-patterns like parameter sprawl, leaky abstractions, nested conditionals, stringly-typed code, TOCTOU, and no-op updates.

Phase 4: Summary & Decision (2-3 minutes)

1. Summarize key concerns
2. Highlight what you liked
3. Make clear decision:
   • ✅ Approve
   • 💬 Comment (minor suggestions)
   • 🔄 Request Changes (must address)
4. Offer to pair if complex

Review Techniques

Technique 1: The Checklist Method

Use checklists for consistent reviews. See Security Review Guide for comprehensive security checklist.

Technique 2: The Question Approach

Instead of stating problems, ask questions:

❌ "This will fail if the list is empty."
✅ "What happens if `items` is an empty array?"

❌ "You need error handling here."
✅ "How should this behave if the API call fails?"

Technique 3: Suggest, Don't Command

Use collaborative language:

❌ "You must change this to use async/await"
✅ "Suggestion: async/await might make this more readable. What do you think?"

❌ "Extract this into a function"
✅ "This logic appears in 3 places. Would it make sense to extract it?"

Technique 4: Differentiate Severity

Use labels to indicate priority:

• 🔴 [blocking] - Must fix before merge
• 🟡 [important] - Should fix, discuss if disagree
• 🟢 [nit] - Nice to have, not blocking
• 💡 [suggestion] - Alternative approach to consider
• 📚 [learning] - Educational comment, no action needed
• 🎉 [praise] - Good work, keep it up!

Severity levels: 🔴 / 🟡 / 🟢 are the three severity tiers used as the standard across all guides in this skill — 🔴 blocks the merge, 🟡 should be addressed, 🟢 is optional. The remaining markers (💡 / 📚 / 🎉) are non-blocking annotations.

Language-Specific Guides

根据审查的代码语言，查阅对应的详细指南：

Cross-Cutting Guides

Language-agnostic patterns applicable to all code reviews:

Additional Resources

• Architecture Review Guide - 架构设计审查指南（SOLID、反模式、耦合度）
• Performance Review Guide - 性能审查指南（Web Vitals、N+1、复杂度）
• Common Bugs Checklist - 按语言分类的常见错误清单
• Security Review Guide - 安全审查指南
• Code Review Best Practices - 代码审查最佳实践
• PR Review Template - PR 审查评论模板
• Review Checklist - 快速参考清单

Source: awesome-skills/code-review-skill — distributed by TomeVault.