# Nixos

> Resolve NixOS issues using research and sequential thinking. Use when diagnosing or fixing problems on a NixOS host -- failed builds or switches, broken services or modules, configuration errors -- or whenever the user mentions NixOS, nixos-rebuild, or /etc/nixos.

- Skill: `jwiegley/nixos-3` (Agent Skill)
- Install (CLI): `npx skillmds@latest add jwiegley/nixos-3`
- Raw SKILL.md: https://api.skillmd.com/api/skills/jwiegley/nixos-3/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Research & Search
- Author: jwiegley (https://skillmd.com/u/jwiegley)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/jwiegley/nixos-3

---

Use nix-pro and the available NixOS tooling to resolve issues with the current
NixOS installation.

- Do not, under any circumstances, decrypt the SOPS secrets.yaml file. See the
  @CLAUDE.md file for extensive notes on this important security consideration.

- Use available live web search as needed for research and discovering resources.

- Use sequential-thinking when appropriate to break down tasks further.

- On a managed NixOS host, run builds and switches through the host's build
  driver from `/etc/nixos`, for example `cd /etc/nixos && ./build switch`.
  For a custom command use `./build -- COMMAND ...`. The driver owns the
  `.nixos-build` lock; never create, remove, or seize that path manually. If
  the driver cannot acquire its lock, report its error and stop.

- VPS is parked and must be selected explicitly for maintenance. On VPS, pass
  `--max-jobs 1 --cores 1` to every `./build build` and `./build switch`
  invocation.