Imported from MidAutumnMoon/TaysiTsuki (AGENTS.md). Install upstream with npx skills add MidAutumnMoon/TaysiTsuki. Copyright stays with the author.

AGENTS.md

What This Is

A NixOS config repo. Flake at the root. Machines in machine/, shared modules in nixos/, custom lib in tsukilib/, packages in packages/, secrets via sops.

Rules

• Do not run nix flake show — it evaluates every output and takes forever.
• Do not run nix build or nixos-rebuild without being asked. They are slow and have side effects.
• When editing Nix files, match the existing style: = alignment, with at module level, let/in blocks for local bindings.

No | tail/ or head

Do not pipe any command output through head or tail, tools will properly handle large output natively.

Fitting New Code

• Recover the domain truth before choosing a shape: valid states, natural owner, boundaries, and relevant failure or resource constraints.
• Give each fact one authoritative home. Prefer representations and APIs that enforce invariants over comments or caller discipline.
• Read the surrounding code first. Extend an abstraction only when the new behavior shares its policy and ownership; otherwise reshape proportionally instead of adding special cases, parallel paths, or copied logic.
• Keep dependencies and data flow explicit. Do not recover required context from ambient state or reconstruct information discarded earlier.
• Design for real pressures, not hypothetical reuse. Preserve existing behavior unless a change is requested; consolidate experiments before landing.

How to Work Here

• To find a machine's config: look in machine/<name>/ — each is a list of NixOS modules.
• To find a module option: grep in nixos/ or tsukilib/.
• To find a package definition: look in packages/.
• Secrets are in sops/, encrypted. Don't try to read encrypted blobs.

Look Things Up

• When unsure about a library, tool, or API, use web search or Context7 before guessing.
• Prefer Context7 for library docs — it pulls real examples and up-to-date signatures.
• Don't hallucinate option names, function signatures, or CLI flags. Look it up.
• Use $CARGO_HOME instead of ~/.cargo.

Dotfile modules (home/*/module.nix)

Each home/<name>/module.nix is a lny submodule config (not a NixOS module), consumed by nixos/users/lny. Returns an attrset of lny options:

• packages — packages added to user profile
• xdg_config."<path>".src/.text — symlink: $XDG_CONFIG_HOME/
• home."<path>".src/.text — symlink: $HOME/
• envvars — environment vars (via environment.d)

The attrname is the destination; .src/.text is the source.

dots (defined in home/module.nix) is a module arg:

• dots.get "<path>" → {{ home }}/TaysiTsuki/home/<path>
• {{ home }} / {{ config }} are jinja templates expanded at activation by the lny binary (see nixos/users/lny), avoiding home-manager round trips.

Communication

• Be concise. Say the thing, stop.
• Don't repeat what I already said or what's already in context.
• Don't pad with disclaimers, summaries, or "hope that helps" type closings.
• If something is wrong, say what's wrong and how to fix it. Don't hedge.