# Defense In Depth

> Use when designing verification strategy so independent gates cover requirements, implementation, security, validation, and judgment without claiming perfect certainty.

- Skill: `dyai2025/defense-in-depth` (Agent Skill)
- Install (CLI): `npx skillmds@latest add dyai2025/defense-in-depth`
- Raw SKILL.md: https://api.skillmd.com/api/skills/dyai2025/defense-in-depth/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Security
- Author: DYAI2025 (https://skillmd.com/u/dyai2025)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/dyai2025/defense-in-depth

---


# Defense in Depth

Design independent, diverse checks so a defect must survive multiple uncorrelated gates.

## Gate design
- Assign an owner.
- Define independence from the implementation author.
- State machine-checkable pass criteria.
- Set loop limits.
- Record evidence and residual risk.

Avoid saying a workflow is 100% safe; report coverage and remaining uncertainty.