## Four cumulative levels

You pick how much time you have today. The skill remembers where you got to, so you can level up later.

- 5 min **Level 1 - Quick scan.** NPM minimum package age, CISA KEV diff against installed software, force-push status on owned repos. This is the weekly-runnable level.
- 15 min **Level 2 - Deep hardening.** Disable force-push, audit SSH config, find loose `.env` files, dependency scan with OSV.dev + GitHub Advisory.
- 1 hour **Level 3 - Blast radius.** Two halves you can pick from. **3A**: encrypted secrets with [varlock](https://github.com/dmno-dev/varlock). **3B**: Docker sandbox so Claude runs containerised.
- Half day+ **Level 4 - Off-machine dev.** Spin up a VPS, harden it, replicate Levels 1-3 there. Get development off your personal machine entirely.

## How to use

Open Claude Code on every machine you develop on (laptop, dev server, all of them). Pick one of the options below.

### Option 1 · Tell Claude to fetch the brief

```
Fetch https://guide.zenaitutoring.com/security-setup/instructions.md and follow the instructions exactly.
```

### Option 2 · Copy the full brief and paste it

[View raw](instructions.md)

After pasting: Claude will recon your machine, ask three short questions, then install `~/.claude/skills/security-audit/SKILL.md`. From then on, run `/security-audit` weekly (Sundays are a good default).

## What gets installed

The skill the agent builds for you (tailored to your OS, package managers, and how you work).

~/.claude/skills/security-audit/SKILL.md

The skill itself. Invoked with `/security-audit`. Knows what level you're at and what to scan.

~/.config/security-audit/state.json

Per-machine memory: level completion, machine role, tracked projects, settled findings, last scan timestamp.

~/.config/security-audit/scans/YYYY-MM-DD-security-audit.md

One dated note per scan. Findings, fixes, anything deferred. Same pattern as the doc-system worklog.

~/.config/security-audit/sources.json

Vulnerability feeds the skill queries: OSV.dev, GitHub Advisory, CISA KEV, NVD. Extensible without editing the skill.

## Why this exists

Supply-chain attacks against NPM maintainers are an active wave - poisoned packages, credential-exfil scripts triggered by pre-commit hooks, force-pushed commits that overwrite history. The 5-minute fix (NPM minimum package age) protects against most of it. The remaining levels stack on top.

The frame is **assume-breach**: encrypted secrets so nothing useful is stolen, read-only skill mounts so the agent can't rewrite its own rules, backups so deletion isn't catastrophic, sandboxes so the blast radius stays contained.