Instruction file imported from dandyrow/dotfiles (.github/instructions/nix.instructions.md). Copyright stays with the author.

Nix-scoped Guidance (applies only to Nix files)

Goals

• Keep changes reproducible and portable across machines.
• Minimise churn: prefer small, focused diffs.
• Preserve the repo's structure: dotfiles live alongside Nix, but Nix logic should remain primarily under nix/.

Rules (do these every time)

• Prefer editing within nix/ for system and Home Manager config; avoid scattering Nix logic into dotfile areas unless the repo already does so.
• Treat flake.nix and flake.lock as the authoritative entrypoints for Nix systems.
• Avoid machine-specific absolute paths and environment-dependent behaviours.
• If you add or change packages/tools, prefer doing so through Nix definitions rather than ad-hoc shell scripts.
• If you change outputs or inputs, consider whether flake.lock needs updating and keep it consistent with flake.nix.

Validation (run when practical)

• Run nix flake check if available and not prohibitively slow for the change.
• If the change impacts a particular host/home configuration, run the relevant build/switch command (if documented in the repo).
• If formatting tools are used in this repo, apply them consistently.

Boundaries

• Never introduce secrets into Nix files.
• Don't restructure modules or rename large paths unless explicitly requested.
• When uncertain, follow existing patterns in nix/ and ask a clarifying question.