# 010107 Code Quality

> Testing practices (vitest, TDD, coverage), security rules (secrets, XSS, injection, CORS), and seed data patterns (anonymization, multi-language).

- Skill: `natuleadan/010107-code-quality` (Agent Skill, multi-file: 6 files)
- Install (CLI): `npx skillmds@latest add natuleadan/010107-code-quality`
- Raw SKILL.md: https://api.skillmd.com/api/skills/natuleadan/010107-code-quality/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Security
- License: MIT
- Author: natuleadan (https://skillmd.com/u/natuleadan)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/natuleadan/010107-code-quality

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# Code Quality Standards

## Overview

Cross-cutting quality standards for testing and security. For TypeScript language rules, see [TypeScript Rules](../010112-typescript-rules/).

## Quick Reference

### Testing

- Use Vitest with `describe`/`it`/`expect`
- Integration tests with `@testing-library/react` + `userEvent`
- Follow AAA pattern: Arrange, Act, Assert
- 80% line coverage, 100% critical paths
- No `.only`, no `.skip`, no testing implementation details

### Security

- No hardcoded secrets — always use env vars
- Validate all input at boundaries (Zod schemas)
- Use parameterized queries to prevent SQL injection
- Prevent open redirects with URL validation
- Sanitize logs to strip secrets
- Never trust client-provided roles

## References

- [Testing](references/testing.md)
- [Security](references/security.md)
- [Seed Data Patterns](references/seed-data-patterns.md) — Anonymization, multi-language, multi-currency seed data conventions