# Code Review

> Perform code reviews. Use when reviewing pull requests, examining code changes, or providing feedback on code quality. Covers security, performance, testing, and design review.

- Skill: `millionco/code-review` (Agent Skill)
- Install (CLI): `npx skillmds@latest add millionco/code-review`
- Raw SKILL.md: https://api.skillmd.com/api/skills/millionco/code-review/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Security
- Author: millionco (https://skillmd.com/u/millionco)
- Updated: 2026-09-10
- Page: https://skillmd.com/skills/millionco/code-review

---


# Code Review

Follow these guidelines when reviewing code.

## Review Checklist

### Identifying Problems

Look for these issues in code changes:

- **Runtime errors**: Potential exceptions, null pointer issues, out-of-bounds access
- **Performance**: Unbounded O(n²) operations, N+1 queries, unnecessary allocations
- **Side effects**: Unintended behavioral changes affecting other components
- **Backwards compatibility**: Breaking API changes without migration path
- **ORM queries**: Complex Django ORM with unexpected query performance
- **Security vulnerabilities**: Injection, XSS, access control gaps, secrets exposure

### Design Assessment

- Do component interactions make logical sense?
- Does the change align with existing project architecture?
- Are there conflicts with current requirements or goals?

### Test Coverage

Every PR should have appropriate test coverage:

- Functional tests for business logic
- Integration tests for component interactions
- End-to-end tests for critical user paths

Verify tests cover actual requirements and edge cases. Avoid excessive branching or looping in test code.

### Long-Term Impact

Flag for senior engineer review when changes involve:

- Database schema modifications
- API contract changes
- New framework or library adoption
- Performance-critical code paths
- Security-sensitive functionality

## Feedback Guidelines

### Tone

- Be polite and empathetic
- Provide actionable suggestions, not vague criticism
- Phrase as questions when uncertain: "Have you considered...?"

### Approval

- Approve when only minor issues remain
- Don't block PRs for stylistic preferences
- Remember: the goal is risk reduction, not perfect code