feat(pi): install the coding agent for a side-by-side trial (task 0020)

Add a `pi` module that turns on the home-manager `programs.pi-coding-agent`
integration for the primary user and freezes a single settings.json: the
default provider set to Anthropic, the default model to Opus (claude-opus-4-8,
Pi's own catalogue id), and analytics disabled. Everything else in
~/.pi/agent — the credential and all self-modification state — is left
unmanaged, so login survives rebuilds and backing Pi out is a one-line enable
flip. Enabled on neogaia alone.

.claude/CONTEXT.md

@@ -0,0 +1,47 @@
+# NixOS Dotfiles
+
+A single flake that builds every machine the user owns — laptop, desktop, and three servers — from one shared, modular configuration.
+
+## Language
+
+**Host**:
+One physical machine the flake builds a NixOS configuration for. Each Host has a directory under `hosts/` holding its machine-specific `hardware-configuration.nix` and its choice of enabled Modules.
+_Avoid_: machine, node, system, box
+
+**Module**:
+A single `.nix` feature file under `modules/` that declares an `enable` option and the configuration it turns on. Every Module is always imported but stays inert until a Host enables it.
+_Avoid_: component, package, plugin
+
+**Skeleton**:
+The flake's plumbing — the Auto-loader, the helper lib, the flake inputs/overlays, and the shared base config — as distinct from the Modules that sit on top of it.
+_Avoid_: framework, core, base, scaffolding
+
+**Auto-loader**:
+The lib code that recursively discovers and imports every Module under `modules/` (and every Host under `hosts/`) so new files wire themselves in without manual `imports` edits.
+_Avoid_: loader, importer, scanner
+
+**Enable convention**:
+The rule that every Module is imported unconditionally and guards its own body with `mkIf config.modules.<path>.enable`, so a Host reads as a checklist of `enable = true` flags.
+_Avoid_: feature flag, toggle, opt-in
+
+**admin identity**:
+The age identity held only in the operator's password manager, never committed, that is a recipient of every secrets file.
+It is the recovery path for any wiped machine and the credential that authorizes registering a new host.
+_Avoid_: master key, admin key, root key
+
+**host identity**:
+The dedicated age key on one machine's encrypted root, generated there and never transmitted, that decrypts that machine's own secrets and the shared file.
+Deliberately distinct from the machine's SSH host key.
+_Avoid_: machine key, node key, host key
+
+**secrets file**:
+One sops-encrypted file in the repo, encrypted to the admin identity plus whichever hosts may read it. Either shared across every host or specific to one.
+_Avoid_: vault, secret store, keyring
+
+**unstable overlay**:
+The overlay exposing `nixpkgs-unstable` packages as `unstable.<name>`, used to pull an individual package fresher than the `nixos-unstable` base.
+_Avoid_: bleeding-edge, latest
+
+**stable overlay**:
+The overlay exposing the latest stable release (`nixos-26.05`) as `stable.<name>`, used to pin an individual package to the rock-solid release from the `nixos-unstable` base.
+_Avoid_: LTS, release channel

.claude/adr/0001-sops-nix-for-secrets.md

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+---
+status: superseded by ADR-0002
+---
+
+# Use sops-nix for secrets
+
+The repo is public, so no secret — including password hashes and the WireGuard/ProtonVPN key — may be committed in plaintext. We manage all secrets with **sops-nix**: encrypted into the repo and decrypted per-host at activation via an age key derived from each machine's SSH host key.
+
+We chose sops-nix over agenix for its multi-recipient encryption (one secret readable by both a host and the admin laptop) and its grouped-file editing workflow, which scale better across the planned five hosts with a mix of shared and per-host secrets. The cost is slightly more upfront machinery than agenix's one-file-per-secret model.
+
+## Consequences
+
+- User/root passwords use `hashedPasswordFile` backed by a sops secret, never a committed hash.
+- Each new host must have its SSH host public key registered as a recipient before it can decrypt its secrets.

.claude/adr/0002-admin-and-host-age-identities.md

@@ -0,0 +1,25 @@
+---
+status: accepted
+---
+
+# Two-tier age identities, secrets in the public repo
+
+Secrets are encrypted with sops-nix into this public repo and decrypted by a two-tier set of age identities: one **admin identity**, stored only in Proton Pass and never committed, which is a recipient of every secrets file; and one **host identity** per machine, a dedicated age key generated on that machine's encrypted root, which reads only its own secrets plus the shared file.
+The admin identity makes secrets recoverable after any machine is wiped and is the credential that authorizes registering a new host; the host identities keep a compromised server from decrypting the laptop.
+Deliberately, a host identity is *not* derived from its SSH host key — that decoupling is what lets the SSH host keys themselves be secrets, so they survive a reimage instead of being regenerated.
+
+This supersedes ADR 0001, whose choice of sops-nix over agenix still holds — the shared-plus-per-host file split with overlapping recipients is exactly the multi-recipient, grouped-file model that decided against agenix — but whose key-derivation mechanism is replaced.
+
+## Considered Options
+
+- **A separate private repository for secrets.** Rejected: cloning it needs credentials that would themselves be bootstrap material during an install, reintroducing a hand-carried secret to protect ciphertext that is already safe to publish.
+- **A passphrase-encrypted admin identity committed to the repo.** Rejected: in a public repo it is offline-brute-forceable indefinitely, whereas a password manager provides the same protection with rate limiting.
+- **Deriving host identities from SSH host keys**, as ADR 0001 specified. Rejected: it forces new host keys on every reimage, which means re-keying every secret, and it makes storing the host keys as secrets circular.
+- **A single admin identity for all hosts, with no per-host identities.** Rejected: with three servers planned, it gives every machine the ability to decrypt every other machine's secrets.
+
+## Consequences
+
+- Every secrets file must include the admin identity as a recipient. A file readable only by its own host becomes permanently unrecoverable the moment that machine is wiped.
+- The admin identity is the single point of recovery, and its durability is now a property of Proton Pass rather than of any machine or repository.
+- A host must have its identity provisioned and registered *before* its first boot, because the login password now arrives only from a decrypted secret and there is no fallback credential.
+- Registering a new host is a re-key of each file's data key, not a re-encryption of its values, so the cost stays constant as the fleet grows.

.claude/skills

@@ -1 +0,0 @@
-../.agents/skills

.claude/spec/laptop-mvi.md

@@ -0,0 +1,92 @@
+## Problem Statement
+
+I'm returning to NixOS after ~2 years away, and I want to start by moving my laptop (`neogaia`, a Dell XPS 13 9380 currently running CachyOS) onto it. My old config still exists but is stale and written in a style I no longer want to copy verbatim. Eventually this same config has to grow to cover my desktop and three servers, so whatever I build for the laptop has to be a clean, scalable foundation — not a throwaway.
+
+Reimaging the laptop is destructive and I only get one machine, so I need a tightly-scoped, well-understood **minimum viable install (MVI)**: the smallest config that boots the laptop into a usable state I can then iterate on live, without risking a half-defined system that strands me at a dead console.
+
+## Solution
+
+Rebuild the `Skeleton` and a single `neogaia` `Host` to the point where the laptop:
+
+- boots from an encrypted disk (LUKS + btrfs + zram),
+- comes up on wifi,
+- lets me log into a console as my user and run `nixos-rebuild switch`,
+- and already carries my core terminal tooling (fish, tmux, nvim, Claude Code).
+
+Everything graphical and everything multi-host is deliberately left for later iterative passes, which are safe because a mistake then is "edit and rebuild," not "reimage." The MVI is the one step that must be right *before* reimaging; the rest is reversible.
+
+The install itself is done from the NixOS live ISO by cloning the repo from my Gitea and running a single `disko-install` against the `neogaia` `Host`, then setting a bootstrap password by hand.
+
+## User Stories
+
+1. As the operator, I want the `Skeleton` rewritten around my old scalable ideas (the `Auto-loader`, the `Enable convention`, per-`Host` layout), so that the config stays legible and shareable across all five future machines without me copying stale code.
+2. As the operator, I want the flake hand-rolled and cleaned up (no framework layer), so that the whole plumbing stays readable in one place for a config that only targets a handful of `x86_64-linux` machines.
+3. As the operator, I want every `Module` auto-discovered and imported but inert until a `Host` sets its `enable` flag, so that each `Host` reads as a checklist of features.
+4. As the operator, I want a `nixos-unstable` base with an `unstable overlay` and a `stable overlay`, so that I can run rolling by default but reach up to bleeding-edge or down to rock-solid on a per-package basis.
+5. As the operator, I want home-manager integrated as a NixOS module with global packages, so that one `nixos-rebuild switch` builds both the system and my user environment atomically.
+6. As the operator, I want my user modelled as an explicit option defaulting to `alexion` (no impure environment lookup), so that the config is reproducible and honest about who the user is.
+7. As the operator, I want the laptop's disk declared with `disko` as encrypted btrfs plus zram swap, so that the install is reproducible and the laptop is encrypted at rest.
+8. As the operator, I want the system to prompt for the LUKS passphrase at boot via systemd-boot and the initrd, so that the encrypted disk unlocks on a normal boot.
+9. As the operator, I want the CachyOS kernel from chaotic-nyx with the chaotic binary cache wired in from the first build, so that I get the performance/feel I'm used to without compiling the kernel from source.
+10. As the operator, I want Intel microcode and the redistributable firmware for the QCA6174 wifi included, so that the laptop's hardware works out of the box.
+11. As the operator, I want NetworkManager enabled, so that I can join wifi easily from the console.
+12. As the operator, I want an SSH daemon running, so that I can drive the rest of the setup remotely if the console is inconvenient.
+13. As the operator, I want my user in `wheel` with a manually-set bootstrap password, so that I can log in and use sudo on first boot without committing any secret to a public repo.
+14. As the operator, I want fish as my default login shell, configured natively via home-manager with my `cachyos-config.fish` translated (greeting, bat-manpager, `done` and bang-bang plugins, helper functions, eza/nav aliases) and all Arch/pacman-specific parts dropped or replaced with NixOS equivalents, so that my shell feels like home but is correct for NixOS.
+15. As the operator, I want tmux configured natively via home-manager using my exact existing `tmux.conf` text, so that my terminal multiplexer is identical to today with no plugin manager needed.
+16. As the operator, I want my nvim config brought in verbatim (lazy.nvim managing its own plugins) via a writable out-of-store symlink, with `git`/`gcc`/`ripgrep`/`fd` provided by Nix, so that my editor is identical to today and lazy.nvim can still update and write its lockfile.
+17. As the operator, I want Claude Code installed declaratively and authenticatable without a browser on the laptop, so that I can use it over the console/SSH via the paste-code flow or an API key.
+18. As the operator, I want timezone `America/New_York`, locale `en_GB.UTF-8`, and console keymap `us` set, so that the base system matches my locale preferences.
+19. As the operator, I want to install by cloning the repo from my Gitea onto the live ISO and running `disko-install` against `neogaia`, so that I avoid self-signed-TLS/auth problems with flake fetching during install.
+20. As the operator, I want the `Skeleton` designed so that per-`Host` disk layouts, per-`Host` kernels, and preserved ZFS pools are all expressible, so that the same foundation extends to the desktop and the three servers later without restructuring.
+
+## Implementation Decisions
+
+**Skeleton**
+- Hand-rolled flake, rewritten and trimmed; no flake-parts.
+- `Auto-loader` rewritten: recursively discovers and imports every `Module` under the modules tree without the old null-placeholder traversal hack; a single discovery helper feeds the `Host` imports. The old `nixosModules` flake output is dropped.
+- Helper lib trimmed to the `Auto-loader`, the host-builder, and the script-from-file helper. `with lib.my` replaced by explicit `inherit`s throughout. `enable` flags use the stdlib enable-option helper rather than bespoke sugar.
+- `nixos-unstable` as the base channel. An `unstable overlay` exposes `nixpkgs-unstable` packages; a `stable overlay` exposes the latest stable release (`nixos-26.05`). chaotic-nyx added as an input with its overlay and binary cache from the start.
+- home-manager sourced from `nix-community`, tracking master with nixpkgs followed, integrated as a NixOS module with global packages and user packages.
+- User modelled as an explicit option defaulting to `alexion`, in `wheel`, driving the system user and the home-manager user in lockstep.
+
+**neogaia Host**
+- Disk declared via `disko`: LUKS-encrypted btrfs with subvolumes plus zram swap. systemd-boot on an EFI system partition; initrd LUKS unlock.
+- CachyOS kernel selected via a small per-`Host` kernel mechanism; chaotic substituter and trusted key in the Nix settings.
+- Intel microcode; redistributable firmware enabled for the QCA6174 wifi. NetworkManager for networking. A zram toggle `Module` enabled here.
+- SSH daemon enabled. Baseline CLI (git, editor, flakes) present. Claude Code installed declaratively.
+- fish `Module`: native home-manager configuration; translated aliases/functions/plugins/init; set as the default login shell. tmux `Module`: native home-manager, exact existing config text inlined. nvim `Module`: verbatim config placed as a writable out-of-store symlink with runtime dependencies provided by Nix.
+- Locale, timezone, and keymap set to the detected values.
+
+**Install flow**
+- Repo pushed to Gitea first. From the NixOS live ISO: join wifi, clone the repo locally, run `disko-install` against the `neogaia` `Host` with the chaotic substituter passed to the install-time daemon, set bootstrap passwords via `nixos-enter`, reboot.
+
+**Secrets (design only in MVI)**
+- Per ADR 0001, secrets use `sops-nix` with age keys derived from each `Host`'s SSH host key. The MVI does not wire any secret, because a `Host`'s age key does not exist until its first install generates the SSH host key. The bootstrap password is set by hand and never committed; moving passwords to a `hashedPasswordFile` backed by a sops secret is the first post-boot task, out of scope here.
+
+## Testing Decisions
+
+- A good test here asserts externally-observable evaluation/build success of the whole `Host`, not the internals of any individual `Module`.
+- **Primary seam (required):** the `neogaia` `Host` evaluates and its system toplevel builds. Building the toplevel drives the entire `Skeleton` — the `Auto-loader` discovering every `Module`, all three overlays resolving, home-manager integration, and every enabled module's config merging without conflict — plus the `disko` layout, which builds from the same tree. Nearly all config-authoring errors surface at this seam short of booting real hardware.
+- No unit-level tests of individual modules; the config-merge model makes the whole-`Host` build the meaningful unit, and it is the highest available seam.
+- Prior art: none in this repo yet (it starts empty); this build-the-toplevel check is the pattern to reuse for every future `Host`.
+- The genuine end-to-end confirmation is the real reimage, which is manual and irreversible by nature and is not automated.
+
+## Out of Scope
+
+- Any graphical environment: Wayland-vs-i3 choice, greeter/display manager, theming (Nord via Stylix or otherwise), fonts, terminal emulator, browser, general desktop apps, gaming (Steam/Lutris/proton-cachyos), emulation.
+- Full `sops-nix` wiring and moving passwords off the bootstrap value (immediate post-boot follow-up, but not MVI).
+- Migrating nvim to a native home-manager configuration with Nix-managed plugins.
+- chaotic-nyx packages beyond the kernel (`mesa-git`, `proton-cachyos`, `scx` schedulers).
+- Flatpak strategy (`nix-flatpak` vs dropping the old imperative helper).
+- The desktop `Host` (`zeus`), including Nvidia.
+- The three servers: deployment model, service migration (plex/arr/kavita/nfs/torrent-through-protonvpn), ZFS wiring and pool import, backups/monitoring, and per-server kernel/channel pinning.
+- VM-based CI (`nixosTest` boot assertions) — explicitly a future addition, not part of this deliverable.
+
+## Further Notes
+
+- **Bootstrap ordering:** the flake must exist on Gitea before the install can consume it, and the manual password step keeps the public repo free of any secret while still yielding a login on first boot.
+- **Gitea is a bootstrap dependency:** every NixOS install pulls the config from self-hosted Gitea, so the Gitea host must stay reachable during any install — relevant when sequencing the servers so the migration never locks the operator out of their own configs.
+- **chaotic cache at install time:** the install-time Nix daemon on the live ISO must have the chaotic substituter configured, or it compiles the CachyOS kernel from source on the USB stick.
+- **Extends to future Hosts by construction:** disk layout, kernel, and channel are all per-`Host` concerns in the `Skeleton`, and existing ZFS pools are preserved by import rather than declared through `disko`. This is what lets the desktop and the three servers join later without reworking the foundation.
+- **Theme target is Nord** (the current CachyOS setup is Nord across terminal, tmux, and nvim), superseding the old repo's Dracula — relevant when the theming branch is grilled.

.claude/spec/pi-coding-agent.md

@@ -0,0 +1,76 @@
+## Problem Statement
+
+I run Claude Code as my coding agent on `neogaia`, wired deeply into this flake: skills, a sudo-guard hook, shared agent instructions, and the whole `.claude/` workflow.
+Pi is a young, fast-moving, self-modifying terminal coding agent that I want to evaluate as an alternative harness.
+I need to install it on the laptop in a way that lets me try it honestly — same model, same account — without unpicking any of the Claude Code setup and without committing myself to Pi before it has earned a permanent place.
+
+The evaluation only means something if the one variable under test is the harness itself, and if backing Pi out later is trivial.
+
+## Solution
+
+Add a new `pi` Module that installs Pi for the primary user on `neogaia`, enabled by the Enable convention like every other feature.
+It flips the home-manager `programs.pi-coding-agent` module on and freezes exactly one file — `settings.json` — pinning the provider and model so Pi runs the same brain as Claude Code (Anthropic, Opus) and disabling analytics so Pi never attempts a runtime write to that frozen file.
+
+Everything else is left to Pi's own writable state directory (`~/.pi/agent/`): no agent context, no skills, no extensions, no keybindings, no custom model providers.
+Pi authenticates by reusing my existing Claude subscription, and that credential is deliberately left unmanaged by the flake so no secret touches the repo and re-auth survives rebuilds — exactly as the `claude-code` Module already treats its login.
+
+The result is a minimal, non-disruptive, side-by-side experiment: Claude Code stays the daily driver, Pi sits alongside it, and removing Pi is a one-line `enable` flip.
+
+## User Stories
+
+1. As the operator, I want Pi installed as its own auto-discovered Module that stays inert until a Host enables it, so that Pi reads as one more `enable = true` line on `neogaia` and never rides silently onto future Hosts.
+2. As the operator, I want Pi enabled only on `neogaia`, so that the experiment is contained to the machine I actually drive.
+3. As the operator, I want Pi to run Anthropic's Opus by default, matching Claude Code's model, so that any difference I observe between the two is attributable to the harness and not the model.
+4. As the operator, I want Pi's provider and default model pinned reproducibly in the flake, so that the same Pi configuration would rebuild identically on any Host.
+5. As the operator, I want Pi's analytics disabled in that same pinned configuration, so that Pi never attempts the one runtime write it would otherwise make to the frozen settings file.
+6. As the operator, I want Pi to authenticate by reusing my existing Claude subscription rather than a separate API key, so that the comparison hits the same account at zero marginal cost.
+7. As the operator, I want Pi's credential left unmanaged by the flake, so that no secret is committed to a public repo and my authentication survives rebuilds.
+8. As the operator, I want Pi installed with no agent context, no skills, and no extensions, so that I see Pi's native behaviour rather than a port of the Claude Code setup.
+9. As the operator, I want Pi to keep full ownership of its writable state directory, so that its self-modifying behaviour — generated extensions, skills, prompt templates, installed packages, sessions — works unimpeded.
+10. As the operator, I want Pi sourced from the base package set and bumped with the normal flake update, so that it stays reasonably fresh without a second package set evaluated for one tool.
+11. As the operator, I want the Module laid out as a directory rather than a single file, so that promoting Pi later — adding rendered skills or extensions — is an additive change rather than a restructure.
+12. As the operator, I want backing Pi out to be a single `enable` flip, so that an experiment that does not pan out leaves no residue.
+
+## Implementation Decisions
+
+**pi Module**
+- A new Module under its own directory, following the shape of the existing `claude-code` Module, declaring a single `enable` option under the `modules` tree and guarding its body with the Enable convention.
+- The directory layout (rather than a single file) is chosen so that later rendering of a skills or extensions source is an additive edit, not a move.
+- On enable, the Module turns on the home-manager `programs.pi-coding-agent` module for the primary user. That upstream module ships the `pi-coding-agent` package (base package set) and manages the state directory's declared files.
+- The Module freezes exactly one file through that upstream module's `settings` option: the default provider set to Anthropic, the default model set to Opus (the exact model-id string confirmed against Pi's own model catalogue at build time), and analytics disabled.
+- No other upstream option is set: `context`, `models`, `keybindings`, `extraPackages`, and `configDir` are all left at their defaults, so home-manager renders nothing but `settings.json` into `~/.pi/agent/` and Pi owns every other path there.
+- Rationale for the single frozen file: among the files the upstream module can render, `settings.json` is the only one Pi writes at runtime, and only its analytics keys — disabling analytics removes even that, so freezing it is safe and never fights Pi's self-modification, which targets other paths entirely.
+- Credentials are out of the flake by design. Pi reuses the Claude subscription via its own login, and the resulting token lives under Pi's state directory, which home-manager does not overwrite — mirroring the `claude-code` Module's treatment of its login.
+- Security posture is inherited, not added: the `claude-code` Module already widens the sudo credential cache system-wide for the primary user, so Pi's `bash` tool can spend a warm credential. Pi does not pass through Claude Code's cold-cache sudo guard, and no equivalent guard is added for Pi in this deliverable. This is an accepted, bounded posture for a supervised single-user experiment.
+
+**neogaia Host**
+- The `neogaia` Host enables the new Module with a single `enable = true`, alongside its existing feature list.
+- No other Host is touched; the desktop and servers do not yet exist in the flake and would each opt in on their own terms.
+
+## Testing Decisions
+
+- A good test here asserts externally-observable evaluation and build success of the whole `neogaia` Host, not the internals of the Module. Installing a Module is config authoring, and the meaningful unit is the Host it composes into.
+- **Primary seam (required, reused):** the `neogaia` Host evaluates and its system toplevel builds via `nix flake check` (the `checks.x86_64-linux.neogaia` target). Building the toplevel drives the Auto-loader discovering the new Module, the `programs.pi-coding-agent` home-manager integration resolving, the frozen `settings.json` rendering, and every enabled Module's config merging without conflict.
+- No new seam is introduced. This is the single high seam that `laptop-mvi.md` established and that every Module in this repo is verified through; an install-a-Module feature does not justify a second one.
+- No unit-level test of the Module in isolation. The config-merge model makes the whole-Host build the highest and most meaningful seam.
+- Prior art: the existing `claude-code`, `gitea-axi`, `fish`, `tmux`, and `nvim` Modules are all verified this way — enabled on `neogaia`, exercised by the toplevel build.
+- The genuine end-to-end confirmation — launching `pi`, authenticating against the Claude subscription, and running the agent — is a manual post-build action on the real machine and is not automated, consistent with how interactive login is handled for Claude Code.
+
+## Out of Scope
+
+- Any harvest/promote pipeline for sharing Pi's self-modifications across machines — rendering a repo-held skills or extensions source into Pi's state directory. Deferred until Pi earns a permanent slot.
+- A shared skill source between Pi and Claude Code for a fairer comparison, exploiting their common `SKILL.md` skill format.
+- A Pi-specific sudo guard (or any tool-permission guard) built as a Pi extension.
+- An `AGENTS.md` context carrying the operator's cross-agent house rules (commit conventions, no attribution trailer, markdown and filename rules). Its absence means Pi's commits will not automatically follow those conventions during the experiment; this is accepted.
+- Custom model providers (`models.json`), custom keybindings, and any non-Anthropic provider.
+- Moving Pi to the `unstable` overlay for head-of-channel freshness.
+- Wiring the credential through a secret store; sops is not yet wired on this Host, and Pi follows the same unmanaged-credential path as Claude Code until it is.
+- Enabling Pi on any Host other than `neogaia`.
+- An ADR recording the "promote agent self-modifications into the flake rather than sync mutable agent state" stance. It is not enacted by this deliverable; if Pi is promoted and the harvest pipeline is built, that becomes a real, repo-wide decision — covering Claude Code too — worth recording then.
+
+## Further Notes
+
+- **Why the single frozen file matters:** Pi's real self-modification surface (generated extensions, skills, prompt templates, installed package code, sessions, trust decisions) lives in paths under `~/.pi/agent/` that the upstream home-manager module never manages, regardless of what the Module declares. Freezing `settings.json` therefore constrains none of it, and disabling analytics removes the only runtime write that file would otherwise receive.
+- **Promotion path is left open by construction:** the directory-shaped Module and the untouched `configDir` mean that, if Pi sticks, a repo-held skills or extensions source can be rendered into the state directory with a writable-directory / read-only-leaf layout — the same mechanism this repo already uses for Claude Code skills — without restructuring anything decided here.
+- **Fair-comparison intent:** matching the model (Opus) and the account (the Claude subscription) is deliberate, so the experiment isolates the harness. Choosing a lighter model or a separate key would introduce a second variable and blur the read.
+- **Reversibility:** because only `settings.json` is frozen and the credential and all self-modification state live outside the flake, disabling the Module removes Pi cleanly, leaving Pi's own state directory as the only residue on disk.

.claude/spec/sops-secrets.md

@@ -0,0 +1,148 @@
+## Problem Statement
+
+`neogaia` is up and running the NixOS it builds, but its login password was set by hand through `nixos-enter` during the install and lives only on that laptop's disk.
+It is the one piece of the machine that is not declared, not reproducible, and not recoverable — a reimage loses it, and no other `Host` can inherit it.
+
+The same gap blocks everything queued behind it.
+An Anthropic API key cannot be provisioned declaratively, a WireGuard key cannot be committed, and the three planned servers cannot carry service credentials.
+The repo is public and mirrored to GitHub, so none of that material can be committed in plaintext.
+
+There is a second, subtler cost.
+SSH host keys are currently generated fresh by `sshd` on each install, so reimaging any machine invalidates its host identity and breaks `known_hosts` for every client that ever connected to it.
+
+`ADR 0001` chose `sops-nix` for this, but its stated mechanism — age keys derived from each `Host`'s SSH host key — turns out to be the wrong topology, and its consequences no longer describe what should be built.
+
+## Solution
+
+Wire `sops-nix` into the `Skeleton` as unconditional plumbing, with a two-tier age identity model.
+
+An **admin identity** stored outside the repo entirely, in Proton Pass, is a recipient of every secrets file.
+It is the durable recovery path: it outlives every machine, is reachable from any device including a live ISO, and is the credential that authorizes adding a new `Host` as a recipient.
+
+A **host identity** — a dedicated age key on each machine's encrypted root — is a recipient of only that machine's own secrets plus the shared file.
+It is generated on the machine, never leaves it, and is deliberately not derived from the SSH host key, which is what frees the SSH host keys to become secrets in their own right.
+
+Secrets are `sops`-encrypted into this same public repo.
+The ciphertext is safe to publish, and the only artifact that would not be — the admin private identity — is never committed at all.
+No second repository is introduced.
+
+The first pass moves the login password off its hand-set value and makes `neogaia`'s SSH host keys stable across reimages.
+That exercises both decryption paths — the early one that runs before user creation, and the ordinary activation one — proving the machinery end to end on the two secrets that are actually needed today.
+
+## User Stories
+
+1. As the operator, I want my login password declared as an encrypted secret rather than typed into a running machine, so that it is reproducible and survives a reimage like everything else in the flake.
+2. As the operator, I want secrets encrypted into the existing public repo rather than a separate private one, so that there is one repository to clone and no bootstrap credential is needed to reach my own configuration during an install.
+3. As the operator, I want an admin identity held in my password manager and never committed, so that nothing brute-forceable is published and I can recover every machine from a device I have never used before.
+4. As the operator, I want each `Host` to hold its own age identity, so that a compromised server cannot decrypt my laptop's secrets.
+5. As the operator, I want a shared secrets file alongside per-`Host` ones, so that material common to every machine is stored once rather than duplicated five times.
+6. As the operator, I want my workstation to be a recipient of only its own secrets, so that the admin identity stays a break-glass credential rather than something sitting unlocked on a laptop.
+7. As the operator, I want `neogaia`'s SSH host keys stored as secrets and restored at activation, so that reimaging the laptop does not invalidate its host identity or break `known_hosts` for clients.
+8. As the operator, I want the secrets machinery to live in the `Skeleton` rather than behind an `enable` flag, so that it reads as plumbing every `Host` depends on rather than an optional feature.
+9. As the operator, I want individual secrets declared next to the configuration that consumes them, so that a reader finds the secret where they find its use.
+10. As the operator, I want a mistyped secret name or a missing secrets file to fail the build, so that errors surface at `nix flake check` rather than at boot.
+11. As the operator, I want the procedure for provisioning a new `Host`'s identity written down, so that installing the desktop and the servers does not require rederiving the key ceremony under pressure.
+12. As the operator, I want the recovery path documented for a machine whose identity was provisioned wrongly, so that a failed first boot is a known procedure rather than an improvised one.
+13. As the operator, I want the editing workflow documented, so that I know which secrets I can change from my laptop and which require unlocking the admin identity.
+
+## Implementation Decisions
+
+**Identity topology**
+
+- Two tiers of recipient: one admin identity, plus one identity per `Host`.
+  Every secrets file is encrypted to admin and to whichever `Host`s legitimately read it.
+- The admin identity is stored as a secure note in Proton Pass and is never committed in any form.
+  Only its public recipient appears in the repo.
+  No passphrase-encrypted copy is committed: the vault already provides passphrase protection with rate limiting, whereas a committed copy would be offline-brute-forceable by anyone who clones the repo, indefinitely.
+- Each `Host` identity is a dedicated age key on the LUKS-encrypted root, generated on that machine and never transmitted.
+  It is *not* derived from the SSH host key.
+  Decoupling them is what allows the SSH host keys to be secrets themselves; deriving one from the other would be circular.
+- An admin recipient on every file is structurally required, not a convenience.
+  A file readable only by its own `Host` becomes permanently unrecoverable the moment that machine is wiped, and adding any new recipient must be done by someone who can already decrypt.
+
+**Repository layout**
+
+- One repository, public, unchanged.
+  A private repository was considered and rejected: cloning it requires credentials that would themselves become bootstrap material at install time, reintroducing the hand-carried secret the design otherwise eliminates, in exchange for protecting content that is already safe to publish.
+- A `sops` configuration file and a secrets directory at the repo root.
+- One secrets file per `Host`, encrypted to admin plus that `Host`.
+- One shared secrets file encrypted to admin plus every `Host`.
+- `neogaia` is a recipient of its own file and the shared file only.
+  Editing another machine's secrets requires unlocking the admin identity for that session, which is the intended friction.
+
+**Secrets in this pass**
+
+- The primary user's password hash lives in the shared file, consumed through `hashedPasswordFile`.
+  It is marked as needed for users, which makes `sops-nix` decrypt it in an earlier activation stage than ordinary secrets, before accounts are created.
+  This is the one ordering subtlety in the design and is the reason the `Host` identity must sit on the root filesystem rather than anywhere later-mounted.
+- Storing the password hash in the shared file rather than per-`Host` is deliberate.
+  The same password will be used on every machine, so duplicating the identical hash across per-`Host` files would not reduce what an attacker learns — it would only make rotation a five-file edit.
+- `neogaia`'s SSH host **private** keys live in its own `Host` file, with `sshd`'s generated host keys disabled and pointed at the decrypted paths instead.
+- SSH host **public** keys are committed in plaintext.
+  They are not secret — publishing them is their function — and encrypting them would impose a re-key cycle every time one changes.
+
+**Placement in the flake**
+
+- The machinery goes in the `Skeleton` as unconditional configuration, not behind an `enable` flag.
+  This is a deliberate departure from the `Enable convention`, on the same grounds as the overlays and the flakes settings: every `Host` will carry secrets, so the flag would be permanently `true`, and the plumbing is not a feature a `Host` chooses.
+- The `Skeleton` carries only the machinery — the flake input, the identity file location, and the default secrets file.
+  Individual secrets are declared wherever they are consumed, so the password secret sits beside the user declaration it feeds and the SSH host keys beside the `sshd` configuration.
+- `sops-nix` is added as a flake input following the base `nixpkgs`.
+
+**Operational procedures**
+
+- For `neogaia`, which is already installed and running, provisioning happens live: generate the identity on the machine, add its recipient, re-key the affected files with the admin identity, rebuild.
+  No reimage and no live ISO are involved.
+- For a `Host` that does not yet exist, provisioning happens on the live ISO *before* the install: generate the identity, add its recipient, re-key, write the identity onto the target root, then install.
+  The first boot then has everything it needs and cannot fail for want of a key.
+  The install already builds from a local clone, so no push is required mid-procedure; the recipient change is committed afterward.
+- Both procedures, the editing workflow, and the live-ISO recovery path are documented in the existing install document rather than a new one.
+
+**Decision record**
+
+- A new ADR supersedes `ADR 0001`, which is marked superseded.
+  `ADR 0001`'s choice of `sops-nix` over `agenix` still holds and carries forward in a sentence, but its key-derivation mechanism is replaced and its stated consequence — that each new `Host` registers its SSH host public key as a recipient — is inverted, since SSH host keys are now secrets rather than the root of trust.
+
+## Testing Decisions
+
+- A good test here asserts externally-observable build and activation behaviour, not the internals of `sops-nix`.
+  Nothing in this feature is our own logic to unit-test; it is configuration wiring, and the meaningful assertions are that the whole `Host` still evaluates and that the secrets actually materialize on a real machine.
+- **Primary seam (required):** `nix flake check` building the `neogaia` system toplevel, the same seam the laptop MVI established.
+  It carries real weight for this feature rather than merely compiling: `sops-nix` validates secrets files at evaluation time by default, so a missing file, a file that is not valid `sops` output, or a declared secret whose key is absent from it all fail the build.
+  Mistyped secret names surface here rather than at boot.
+- **Confirmation (manual):** a real activation on `neogaia`.
+  This is what proves decryption itself — that the `Host` identity is readable at the right stage, that secrets appear with the declared ownership and mode, that `sshd` adopts the restored host keys, and that login works against `hashedPasswordFile`.
+  It cannot be automated without a machine that holds a real identity, and is treated like the reimage in the laptop MVI: manual by nature.
+- No new seams are introduced.
+  The existing whole-`Host` build remains the highest available point, and the config-merge model makes it the meaningful unit.
+- Prior art: the toplevel-build check established by the laptop MVI, already wired as the flake's `checks` output.
+
+## Out of Scope
+
+- The Anthropic API key.
+  It is the natural next secret, but it is consumed as an environment variable rather than a file path, and conflating that shape with the bootstrap work would obscure both.
+- The WireGuard/ProtonVPN key, which has no `Module` to consume it yet.
+- Declarative wifi credentials.
+  NetworkManager profile secrets are fiddly and joining from the console currently works.
+- Fleet-wide SSH host verification.
+  With one `Host` there is nothing to verify against, and the choice of whether to identify machines by name or address should be made when a second machine exists and the answer is known rather than guessed.
+- Provisioning any identity for a `Host` that does not exist yet.
+  The procedure is documented; no key is generated for `zeus` or the servers.
+- Rotating the LUKS passphrase or coupling it to secret decryption.
+- Hardware-token identities.
+  A YubiKey can be added later as an additional admin recipient without changing any decision here.
+- Any change to how the flake is fetched during an install.
+
+## Further Notes
+
+- **The lockout risk is confined to fresh installs.**
+  On `neogaia` the transition is safe: if activation fails, the rebuild fails and the running generation persists with the existing hand-set password intact.
+  A machine being installed for the first time has no such fallback, because the password now arrives only from a decrypted secret — which is exactly why its identity is provisioned before the first boot rather than after it.
+- **The admin identity is the single point of recovery**, and its durability is now a property of Proton Pass rather than of any machine or repository.
+  Losing the vault without a backup means losing the ability to add recipients or recover a wiped `Host`, even though every currently-running machine keeps working from its own identity.
+- **Stable SSH host keys were nearly given up** in favour of deriving identities from them, and were recovered by inverting the dependency.
+  The rule that made it work generalizes: exactly one secret per machine must arrive out of band, and making that one thing a purpose-built key rather than a repurposed one keeps everything else declarable.
+- **Adding a `Host` is a re-key, not a re-encrypt.**
+  A `sops` file holds a single data key encrypted once per recipient, so registering a new machine rewrites only that metadata, and the cost stays constant as the fleet grows to five.
+- **This is what `ADR 0001` chose `sops-nix` for.**
+  The shared-plus-per-`Host` file split with overlapping recipients is precisely the multi-recipient, grouped-file model that decided against `agenix`; the topology change replaces how identities are obtained, not why the tool was picked.

.claude/tasks/0001-skeleton-and-building-host.md

@@ -0,0 +1,37 @@
+---
+spec: laptop-mvi
+---
+
+## What to build
+
+Stand up the `Skeleton` and a minimal `neogaia` `Host` that evaluates and whose system toplevel builds — the walking skeleton every later slice extends and re-verifies against.
+
+The `Skeleton` is a hand-rolled flake (no flake-parts): `nixos-unstable` base channel, an `unstable overlay` exposing `nixpkgs-unstable` as `unstable.<name>`, a `stable overlay` exposing `nixos-26.05` as `stable.<name>`, and chaotic-nyx wired as an input with its overlay and binary cache.
+The helper lib is trimmed to three pieces: the `Auto-loader` (recursively discovers and imports every `Module` under `modules/` and every `Host` under `hosts/` with no null-placeholder traversal hack), the host-builder, and the script-from-file helper.
+`with lib.my` is not used — dependencies are `inherit`ed explicitly.
+The `Enable convention` uses the stdlib enable-option helper; every `Module` is imported unconditionally and guards its body with `mkIf config.modules.<path>.enable`.
+home-manager is sourced from `nix-community` (master, nixpkgs followed) and integrated as a NixOS module with global packages and user packages.
+The `user` is an explicit option defaulting to `alexion` (no impure environment lookup), placed in `wheel`, driving the system user and the home-manager user in lockstep.
+The `neogaia` `Host` carries only enough (placeholder `hardware-configuration.nix`, filesystems/bootloader stubs, `stateVersion`) to make `nixosConfigurations.neogaia.config.system.build.toplevel` evaluate and build; real disk/kernel/networking arrive in later slices.
+
+Design the per-`Host` layout so disk layout, kernel, and channel are all per-`Host` concerns from the start (story 20), so the desktop and servers extend this foundation without restructuring.
+
+## Acceptance criteria
+
+- [x] `nix flake check` succeeds and the flake exposes `nixosConfigurations.neogaia`.
+- [x] `nixosConfigurations.neogaia.config.system.build.toplevel` builds.
+- [x] Adding a new `.nix` file under `modules/` is auto-discovered and imported without editing any `imports` list, and stays inert until its `enable` flag is set.
+- [x] All three overlays resolve: `unstable.<pkg>`, `stable.<pkg>`, and a chaotic-nyx package are each reachable in a `Host`.
+- [x] home-manager builds as part of the same `nixos-rebuild switch` toplevel (system + user environment atomic).
+- [x] The `user` option defaults to `alexion`, has no impure environment lookup, places the user in `wheel`, and drives both the system and home-manager user.
+- [x] The old `nixosModules` flake output and the `with lib.my` idiom are absent.
+
+## Implementation Notes
+
+- **Verification.** `nix flake check` builds `checks.x86_64-linux.neogaia` = the Host toplevel (the spec's primary seam). Overlays confirmed via `nix eval` of `pkgs.unstable.hello` (2.12.3), `pkgs.stable.hello` (2.12.1), and `pkgs.linuxPackages_cachyos.kernel` (7.1.3, from chaotic). Auto-loader inertness confirmed both ways: the reference `modules/example.nix` is off by default, and `extendModules` with `modules.example.enable = true` activates its body.
+- **chaotic binary cache.** Wired via `inputs.chaotic.nixosModules.default`, which puts both the `nyx-cache.chaotic.cx` substituter and its trusted public key into the built config (verified by evaluating `config.nix.settings.substituters`/`trusted-public-keys`). chaotic deliberately does **not** follow our nixpkgs, so the cache stays usable. Making the substituter/key explicit is task 0003's concern; here it is inherited from the module.
+- **Shared base lives in `system/`.** The Skeleton's shared base config (overlays, `user`, flakes, home-manager wiring) is a `system/` module always imported by the host-builder, kept separate from the auto-loaded feature `Module`s under `modules/` so the base is never gated by an `enable` flag.
+- **`modules/example.nix` kept intentionally.** It is the Auto-loader / Enable-convention reference every real Module copies; remove it once a real Module supersedes its teaching value.
+- **`scriptFromFile` present but unused.** The task mandates the helper lib carry it ("the script-from-file helper"); its first caller lands with a later Module.
+- **Home-manager base user only.** The base sets `home.username`/`homeDirectory`/`stateVersion` for the `user`; `extraSpecialArgs` passes both `inputs` and `my` (the flake lib) so upcoming HM Modules (fish/tmux/nvim) can reach `scriptFromFile`.
+- **Deviations from plan.** Added an `options.user.description` (GECOS) alongside `user.name` — small and expected for a real account. Baseline `git` + global `allowUnfree` are set in the base (git is required for flakes; unfree is needed by chaotic/home-manager and later Claude Code). Placeholder `fileSystems`/bootloader and `hardware-configuration.nix` in `neogaia` are stubs that task 0002 (disko) replaces.

.claude/tasks/0002-neogaia-disk-and-boot.md

@@ -0,0 +1,31 @@
+---
+spec: laptop-mvi
+blocked-by: 0001-skeleton-and-building-host
+---
+
+## What to build
+
+Declare the `neogaia` laptop's disk with `disko` and make it unlock and boot on real hardware: a LUKS-encrypted btrfs volume with subvolumes plus zram swap, on an EFI system partition using systemd-boot, with the LUKS passphrase prompted at boot via the initrd.
+
+The layout must build from the same tree as the `Host` toplevel (so the whole-`Host` build exercises it), and must be expressed as a per-`Host` disk concern so other machines can declare their own layouts later.
+
+## Acceptance criteria
+
+- [x] `neogaia` declares a `disko` layout: LUKS-encrypted btrfs with subvolumes plus zram swap on an EFI system partition.
+- [x] systemd-boot is the bootloader; the initrd prompts for the LUKS passphrase so a normal boot unlocks the encrypted disk.
+- [x] The `disko` layout builds as part of the `neogaia` toplevel build (no separate invocation needed to catch layout errors).
+- [x] The disk layout is a per-`Host` concern, expressible differently for future `Host`s without restructuring the `Skeleton`.
+
+## Implementation Notes
+
+- **Layout.** One GPT disk at `/dev/nvme0n1`: a 512M EF00 ESP (vfat, `umask=0077`) mounted at `/boot`, and a 100%-fill LUKS partition (`cryptroot`, `allowDiscards`) holding a btrfs filesystem with three subvolumes — `@root` → `/`, `@home` → `/home`, `@nix` → `/nix` — each mounted `compress=zstd,noatime`.
+  There is deliberately no on-disk swap partition; swap is RAM-backed zram.
+- **Skeleton vs. per-Host split.** The disko *module* (`inputs.disko.nixosModules.disko`) is wired into the host-builder in `lib/default.nix`, so every `Host` can interpret a `disko.devices` declaration; the *layout itself* lives in `hosts/neogaia/disk.nix`.
+  A future `Host` declares a different layout, or none at all (an undeclared `disko.devices` is a no-op), so servers that preserve an existing pool by import need no `Skeleton` change.
+- **disko input follows nixpkgs.** Unlike chaotic (which must not), disko follows our `nixpkgs` so it builds against the same base.
+- **Boot unlock.** disko's `type = "luks"` (no key file) generates `boot.initrd.luks.devices.cryptroot`, so the classic initrd prompts for the passphrase on a normal boot; the `nvme` initrd module was already present in `hardware-configuration.nix`.
+- **zram enabled directly, not yet a Module.** Criterion 1 requires "plus zram swap," so `zramSwap.enable = true` is set on the `Host` now.
+  Task 0003 owns the reusable zram toggle `Module` and will lift this line into it; the placeholder `fileSystems`/bootloader stubs from task 0001 are removed here since disko now derives `fileSystems`.
+- **Verification.** `nix flake check` (the `checks.x86_64-linux.neogaia` toplevel) builds green.
+  Confirmed via `nix eval`: disko-derived `fileSystems` = `/`,`/home`,`/nix` on btrfs `/dev/mapper/cryptroot` + `/boot` on the ESP; `boot.initrd.luks.devices` = `["cryptroot"]`; `systemd-boot.enable` and `zramSwap.enable` both true; `swapDevices` empty.
+  The genuine end-to-end confirmation is the manual `disko-install` reimage, which is irreversible by nature and not automated.

.claude/tasks/0003-kernel-and-hardware.md

@@ -0,0 +1,26 @@
+---
+spec: laptop-mvi
+blocked-by: 0001-skeleton-and-building-host
+---
+
+## What to build
+
+Give `neogaia` the kernel and hardware enablement it needs to run well on the Dell XPS 13 9380: the CachyOS kernel pulled as a binary from chaotic-nyx (not compiled from source), Intel microcode, and the redistributable firmware for the QCA6174 wifi. Add a zram toggle `Module` and enable it here.
+
+The kernel is selected through a small per-`Host` kernel mechanism so other `Host`s can choose different kernels. The chaotic substituter and its trusted public key are added to the Nix settings so the kernel is fetched from the binary cache from the first build.
+
+## Acceptance criteria
+
+- [x] `neogaia` runs the CachyOS kernel selected via a per-`Host` kernel mechanism, sourced from chaotic-nyx.
+- [x] The chaotic substituter and trusted public key are in the Nix settings, so the kernel is fetched from cache rather than compiled.
+- [x] Intel microcode is enabled.
+- [x] Redistributable firmware is enabled so the QCA6174 wifi hardware is available.
+- [-] A zram toggle `Module` exists (following the `Enable convention`) and is enabled on `neogaia`. — Module dropped in PR review; zram is enabled inline on `neogaia` instead (see notes).
+- [x] The `neogaia` toplevel still builds with all of the above.
+
+## Implementation Notes
+
+- **Per-`Host` kernel mechanism = native `boot.kernelPackages`.** neogaia sets `boot.kernelPackages = pkgs.linuxPackages_cachyos` directly in its Host directory (`hosts/neogaia/default.nix`). No custom wrapper option was added: `boot.kernelPackages` is already a per-`Host` setting, so other `Host`s pick their own kernel the same way. A string→package wrapper would have been premature abstraction with one `Host` and one kernel, so it was deliberately left out; the "mechanism" is the per-`Host` placement of the native option.
+- **Substituter/key live in the shared base, via the `extra-` options.** They were added to `system/default.nix` (shared by every `Host`), not just neogaia, because the chaotic module is wired for all `Host`s and the cache is general plumbing. `nix.settings.extra-substituters` / `extra-trusted-public-keys` are used rather than the replacing `substituters` / `trusted-public-keys`, so `cache.nixos.org` (and any other substituter) is only appended to, never dropped. chaotic's own module also provides these entries; the explicit declaration is belt-and-suspenders and keeps the built system's cache config visible and independent of that module.
+- **Dev-host build needed a daemon-level cache.** Building the toplevel here first compiled the CachyOS kernel (and rustc bootstrap) from source, because the build daemon's `/etc/nix/nix.conf` had no `nyx-cache` substituter — the built system's `nix.settings` do not govern the daemon doing the build, and the dev user is a non-trusted client that cannot add substituters from the CLI. Adding `extra-substituters`/`extra-trusted-public-keys` for `nyx-cache` to `/etc/nix/nix.conf` (sudo) and restarting `nix-daemon` fixed it; the build then fetched the kernel (7.1.3) from the cache. Recorded as a gotcha in `CLAUDE.md`.
+- **zram is enabled inline, not as a `Module` (criterion 5 dropped).** The task asked for a zram toggle `Module`, and one was built first (`modules/zram.nix`), but PR review rejected it as a single-line abstraction that wraps the native `zramSwap.enable` toggle without adding anything. It was removed, and `neogaia` sets `zramSwap.enable = true` directly, as it did before task 0003. The `Enable convention` reference remains `modules/example.nix`; real feature `Module`s arrive with fish/tmux/nvim/Claude Code in later tasks.

.claude/tasks/0004-networking-and-base-system.md

@@ -0,0 +1,28 @@
+---
+spec: laptop-mvi
+blocked-by: 0001-skeleton-and-building-host
+---
+
+## What to build
+
+Make the booted laptop a usable console I can log into and reach remotely: NetworkManager for joining wifi, an SSH daemon for driving the rest of the setup over the network, and the base locale settings.
+
+Set timezone `America/New_York`, locale `en_GB.UTF-8`, and console keymap `us`.
+
+## Acceptance criteria
+
+- [x] NetworkManager is enabled so wifi can be joined from the console.
+- [x] An SSH daemon is enabled so the machine can be driven remotely.
+- [x] Timezone is `America/New_York`, locale is `en_GB.UTF-8`, console keymap is `us`.
+- [x] The `neogaia` toplevel still builds with all of the above.
+
+## Implementation Notes
+
+- **Placement in the Host, not a Module.** NetworkManager, the SSH daemon, and the locale/timezone/keymap settings all live directly in `hosts/neogaia/default.nix`, alongside the kernel/hardware/zram lines from task 0003.
+  This follows the precedent set in that task, where a speculative enable-gated Module was dropped in review in favour of inlining for the single-Host MVI.
+  A shared locale Module or a networking Module can be extracted later when a second Host actually needs the same settings; extracting now would be speculative generality.
+- **SSH left unhardened deliberately.** `services.openssh.enable = true` keeps NixOS's default password authentication on.
+  This is required by the install flow: first-boot access is over SSH with the hand-set bootstrap password, and no SSH keys or sops-derived age key exist until the install generates the Host's SSH host key.
+  Moving to key-only auth / `hashedPasswordFile` is the first post-boot follow-up per the spec's Secrets section, out of scope for the MVI.
+- **Locale/timezone mix is as specified.** `i18n.defaultLocale = "en_GB.UTF-8"` with `time.timeZone = "America/New_York"` and `console.keyMap = "us"` mixes region and locale; this matches the operator's stated preferences verbatim and is intentional.
+- **Verification.** Built the primary seam — `nix build .#checks.x86_64-linux.neogaia` (the Host toplevel) — to exit 0; the systemd units for `wpa_supplicant` (NetworkManager's backend) and openssh appear in the build. The five option values were also confirmed via `nix eval`.

.claude/tasks/0005-fish-shell-module.md

@@ -0,0 +1,44 @@
+---
+spec: laptop-mvi
+blocked-by: 0001-skeleton-and-building-host
+---
+
+## What to build
+
+A fish `Module`, configured natively via home-manager, that makes the shell feel like the current CachyOS setup but is correct for NixOS. Translate the existing `cachyos-config.fish` and the rest of the fish snapshot under `reference/home/.config/fish/`: the greeting, the bat-manpager, the `done` and bang-bang plugins, the helper functions, and the eza/nav aliases. Drop or replace every Arch/pacman-specific part with its NixOS equivalent. Set fish as the default login shell.
+
+Configure the plugins natively through home-manager rather than a fish plugin manager.
+
+## Acceptance criteria
+
+- [x] A fish `Module` (following the `Enable convention`) is enabled on `neogaia` and configured natively via home-manager.
+- [x] The greeting, bat-manpager, `done` and bang-bang plugins, helper functions, and eza/nav aliases from the reference config are reproduced.
+- [x] All Arch/pacman-specific parts are dropped or replaced with NixOS equivalents.
+- [x] fish is the user's default login shell.
+- [x] The `neogaia` toplevel still builds with the fish `Module` enabled.
+
+## Implementation Notes
+
+- **Plugins are native, not inlined.** `done` and `bang-bang` come from `pkgs.fishPlugins.*` via `programs.fish.plugins`; home-manager drops them into `~/.config/fish/conf.d/` where fish auto-sources them.
+  The reference config inlined the bang-bang `__history_previous_command` functions and binds by hand; the plugin supplies those, so they are not re-inlined.
+- **`done` tuning uses `set -g`, not `set -U`.** The reference set `__done_min_cmd_duration`/`__done_notification_urgency_level` as universal variables, which persist to the universal-variable file and then ignore config changes.
+  A declarative config must own these each session, so they are set global (`set -g`) in `interactiveShellInit`.
+- **Arch/pacman aliases dropped:** `grubup`, `fixpacman`, `mirror` (`cachyos-rate-mirrors`), `apt`/`apt-get` (`man pacman`), `big` (`expac`), `gitpkg`, `rip` (`expac`).
+  **Replaced with NixOS equivalents:** `update` → `sudo nixos-rebuild switch` (was `pacman -Syu`), `cleanup` → `sudo nix-collect-garbage -d` (was `pacman -Rns`).
+- **Machine-specific PATH hacks dropped, per spec story 6 ("no impure environment lookup").** The hardcoded `BUN_INSTALL`, the `node-v24...` tarball path, and `~/Applications/depot_tools` from `config.fish` are absolute/impure and are not reproduced; such tooling should be Nix-provided when its own Module arrives.
+  The portable bits are kept: `~/.local/bin` on PATH (guarded) and sourcing `~/.fish_profile`.
+- **`env.fish` and `rustup.fish` deliberately not carried over.** `ANDROID_HOME`/platform-tools (Android SDK) and `source ~/.cargo/env.fish` (rust) are dev-toolchain integrations outside the MVI's core tooling (fish/tmux/nvim/Claude Code); they belong to future per-toolchain Modules that provide those tools through Nix rather than sourcing an impure env file.
+- **`hw` (`hwinfo --short`) and `tb` (`nc termbin.com 9999`) dropped.** These are generic rather than pacman-specific, but each needs an extra package (`hwinfo`, a `netcat`) that the minimal install does not otherwise pull in; left out of the MVI and easy to add later.
+- **`copy` kept verbatim** (including the upstream `trim-right` call) to preserve exact parity with the current shell.
+- **Verification.** The `neogaia` system toplevel builds (the spec's primary seam).
+  The rendered `~/.config/fish/` was inspected in the build output: aliases, the three helper functions, the `fastfetch` greeting, the bat manpager, the `done` tuning vars, and the `conf.d/plugin-done.fish` + `conf.d/plugin-bang-bang.fish` plugin files are all present; `users.users.alexion.shell` resolves to `pkgs.fish`.
+
+### Post-review adjustments
+
+- **`defaultShell` option.** Setting fish as the login shell moved behind `modules.fish.defaultShell` (default `false`, gated with `mkIf`); `neogaia` opts in explicitly. Enabling the Module alone no longer changes the login shell.
+- **Abbreviation-first.** Every non-eza alias is now a `shellAbbr` (the eza `ls` family stays an alias), `preferAbbrs = true`, and `generateCompletions = true` is pinned rather than left to the upstream default.
+- **vi command-line editing.** `interactiveShellInit` sets `fish_key_bindings fish_vi_key_bindings`; the `bang-bang` plugin re-binds `!`/`$` in insert mode via its own `--on-variable fish_key_bindings` handler, so the switch keeps them working.
+- **Trimmed aliases.** Navigation capped at four dots (`.....`/`......` dropped); `psmem`, `psmem10`, `dir`, `vdir`, and `please` removed.
+- **Interactive init lives in a real fish file.** The Module lives at `modules/fish/fish.nix`; its `interactiveShellInit` is `builtins.readFile ./config.fish`, so the interactive init is written as one editable fish file (vi editing, `EDITOR`/`VISUAL`, the bat manpager, the done plugin tuning, and `~/.local/bin`/`~/.fish_profile`) that home-manager renders into `~/.config/fish/config.fish`. The file is small enough that splitting it into fragments was not worth the indirection; Nix inlines it at build time, so nothing of ours is autoloaded from a separate runtime file.
+- **`copy` stays a function file.** `functions/copy.fish` holds the non-trivial `copy` body, read into the `functions` option; fish autoloads function files lazily, so that is the idiomatic home for a function. Trivial one-liner functions stay inline in `fish.nix`.
+- The Auto-loader only collects `.nix`, so every `.fish` file under `modules/fish/` is inert to it.

.claude/tasks/0006-tmux-module.md

@@ -0,0 +1,43 @@
+---
+spec: laptop-mvi
+blocked-by: 0001-skeleton-and-building-host
+---
+
+## What to build
+
+A tmux `Module`, configured natively via home-manager, that reproduces the current terminal multiplexer exactly: the existing `tmux.conf` text (under `reference/home/.config/tmux/`) inlined verbatim, with no plugin manager needed.
+
+## Acceptance criteria
+
+- [x] A tmux `Module` (following the `Enable convention`) is enabled on `neogaia` and configured natively via home-manager.
+- [x] The existing `tmux.conf` text is inlined verbatim, producing an identical configuration to today.
+- [x] No tmux plugin manager is used.
+- [x] The `neogaia` toplevel still builds with the tmux `Module` enabled.
+
+## Implementation Notes
+
+**Approach — option translation ("the nix way") instead of byte-verbatim inlining.**
+On the operator's explicit call ("I would prefer to do things the nix way. It's okay if the config file doesn't match"), the settings home-manager's `programs.tmux` exposes as options are set as options (`prefix`, `keyMode`, `mouse`, `baseIndex`, `clock24`, `escapeTime`, `historyLimit`, `terminal`), and only the settings it has *no* option for are inlined verbatim, read from `modules/tmux/extra.conf` via `builtins.readFile`.
+The generated `~/.config/tmux/tmux.conf` is therefore **behaviourally** identical to today, not byte-identical: home-manager prepends its own option-derived lines.
+This was preferred over `xdg.configFile.source = ./tmux.conf` (which would have been byte-identical) after weighing both.
+Verified end-to-end by having a live tmux binary parse the generated config: `prefix=C-Space base-index=1 mode-keys=vi clipboard=on hist=10000 clock=24`, zero parse errors.
+
+**`clock24 = true` is required, not cosmetic.**
+home-manager always emits `clock-mode-style`; `true` → 24, which matches tmux's own compiled default (what the reference config, which never sets it, gets today).
+Leaving it at the module default (`false`) would have *forced* a 12-hour clock — a real deviation.
+
+**Pane navigation stays in `extra.conf`.**
+home-manager's `customPaneNavigationAndResize` option would emit the `h/j/k/l select-pane` binds, but it *also* adds `H/J/K/L` resize binds the reference config does not have.
+To stay faithful, the `h/j/k/l` binds are inlined in `extra.conf` and the option is left off.
+
+**`secureSocket` left at the home-manager default (`true`).**
+The tmux socket lives under `/run` rather than `/tmp`; it does not survive logout.
+This differs from stock tmux behaviour and was accepted deliberately.
+
+**Comments in `extra.conf` rewritten to the project convention.**
+The reference `tmux.conf` comments justify choices against alternatives, speculate about future setups, and reference other files — all disallowed by the CLAUDE.md comment convention.
+Since `extra.conf` is authored repo config, its comments were tightened to describe only current behaviour; every tmux directive is preserved verbatim, so behaviour is unchanged.
+
+**Version-sensitivity (not a defect today).**
+`programs.tmux.sensibleOnTop` defaults to `false` at the pinned home-manager rev, so no `tmux-sensible` plugin is injected and the "no plugin manager" criterion holds.
+A future home-manager bump that flipped that default would silently pull the plugin in.

.claude/tasks/0007-nvim-module.md

@@ -0,0 +1,24 @@
+---
+spec: laptop-mvi
+blocked-by: 0001-skeleton-and-building-host
+---
+
+## What to build
+
+An nvim `Module` that gives the primary user Neovim configured declaratively through **nixvim**, with **functional parity** to the operator's existing config.
+Parity is about the "what" — the same plugins, keymaps, options, colorscheme, and behaviour — not the "how".
+The mechanism is deliberately free to follow NixOS's declarative paradigm rather than transplanting the imperative lazy.nvim setup: plugins are managed by Nix (no plugin manager, no runtime cloning, no lockfile), and as much of the config as possible is expressed as typed Nix, with raw Lua kept only as an escape hatch.
+
+## Acceptance criteria
+
+- [x] An nvim `Module` (following the `Enable convention`) is enabled on `neogaia`.
+- [x] Neovim is configured via **nixvim**, wired as a flake input (`nixvim.inputs.nixpkgs.follows = "nixpkgs"`), consumed as its home-manager module under `home-manager.users.<user>.programs.nixvim`.
+- [x] Functional parity with the previous config: the same plugins (neogit, diffview, gitsigns, oil, snacks, gbprod-nord, render-markdown, which-key, treesitter), keymaps, `vim` options, the `nord` colorscheme, the Neogit blame-toggle autocmd, and markdown concealment — verified headless against the generated config.
+- [x] Runtime dependencies `git`, `ripgrep`, and `fd` are provided by Nix; `gcc` is not needed because Nix builds the treesitter grammars.
+- [x] The `neogaia` toplevel still builds with the nvim `Module` enabled.
+
+## Implementation Notes
+
+- **nixvim, typed Nix first.** `modules/nvim/nvim.nix` enables `programs.nixvim` with `opts`, `globals`, `keymaps`, and typed `plugins.*` settings. Treesitter uses `plugins.treesitter` (`highlight.enable`, `indent.enable`, `grammarPackages` from the module's own `builtGrammars`) covering nix, lua, bash, fish, markdown, rust, python, java, kotlin, c, cpp, html, css, javascript, typescript, go.
+- **The imperative remainder** — the `gbprod/nord.nvim` setup + colorscheme call, the markdown `conceallevel` autocmd, and the Neogit blame-toggle `BufUnload` autocmd — lives in `modules/nvim/config.lua`, pulled in via `extraConfigLua = builtins.readFile ./config.lua`. `gbprod-nord` comes in through `extraPlugins` because nixvim's `colorschemes.nord` is a different plugin.
+- **Verification.** `nix build .#…programs.nixvim.build.package` exits 0 and the whole toplevel evaluates. The generated config was exercised headless (launched with `-u` the generated init and a scratch `HOME`, since the wrapper otherwise loads the dev host's real `~/.config/nvim`): all options, keymaps, plugins, the `nord` colorscheme, treesitter highlight + indent, and markdown conceal load with no errors.

.claude/tasks/0008-claude-code-module.md

@@ -0,0 +1,23 @@
+---
+spec: laptop-mvi
+blocked-by: 0001-skeleton-and-building-host
+---
+
+## What to build
+
+Install Claude Code declaratively on `neogaia`, and make it authenticatable without a browser on the laptop so it can be used over the console/SSH via the paste-code flow or an API key.
+
+## Acceptance criteria
+
+- [x] Claude Code is installed declaratively (following the `Enable convention` if expressed as a `Module`) and enabled on `neogaia`.
+- [x] The browserless authentication path (paste-code flow or API key) is documented so it works over console/SSH.
+- [x] The `neogaia` toplevel still builds with Claude Code included.
+
+## Implementation Notes
+
+- **Native home-manager module, not a raw package.** Claude Code is enabled through home-manager's own `programs.claude-code` module (`home-manager.users.<user>.programs.claude-code.enable = true`), mirroring how `tmux`/`fish` use their native home-manager options rather than dropping a package into `home.packages`. The module ships within home-manager itself, so — unlike `nvim`/nixvim — no new flake input is needed. Per the invocation's steer to prefer the tmux/nvim conventions over the task wording, the feature `Module` at `modules/claude-code/claude-code.nix` is kept as thin as the `tmux` module: just the `enable` option and the delegation.
+- **No settings written.** The module manages no `~/.claude` contents and writes no `settings.json`, so login and first-run configuration stay interactive. This keeps auth material (subscription token or API key) out of the repo.
+- **Auth docs co-located with the module.** The browserless authentication guide lives at `modules/claude-code/authentication.md`, next to the module, following the repo pattern where each module directory holds its own supporting files. It covers both the paste-code OAuth flow (open the printed URL on another device, paste the code back — works unchanged over SSH) and the `ANTHROPIC_API_KEY` path. This is distinct from task 0009's OS-install docs, which cover `disko-install`, not the CLI login.
+- **Verification.** `nix build .#checks.x86_64-linux.neogaia` (the primary Host seam) builds the toplevel with `claude-code-2.1.209` included; `config.modules.claude-code.enable` and the home-manager `programs.claude-code.enable` both evaluate `true`.
+- **Note on flake evaluation.** The new module file had to be `git add`ed before the flake could see it — flakes evaluate the git tree, so an untracked Module is invisible to the Auto-loader and the host errors with "option does not exist".
+- **Personal config ported into the Module (beyond the acceptance criteria).** At the operator's request the declarative half of `~/.claude` now lives in the Module and is applied when it is enabled: the global agent instructions (`context = ./CLAUDE.md`), the skills tree (`skills = ./skills`, 15 skills), the attention-bell hook (`hooks."attention-bell.sh"`), and `settings.json` (`model = "opus"` plus the Stop/Notification/SessionStart hook wiring). Runtime state (`projects/`, `plugins/`, `cache/`, `history.jsonl`, sessions) and the `~/.claude/.credentials.json` secret are deliberately left out, so login survives rebuilds and no secret enters the repo. Stale `agents`/`commands` symlinks (into an outdated `~/wrk/claude`) were skipped. Verified against the built `home-files`: `~/.claude/{CLAUDE.md,settings.json,skills/,hooks/attention-bell.sh}` are all generated, with the hook executable. The `gitea-axi` SessionStart hook depends on that binary being on `PATH`; the flake does not yet provide it, so the hook is a no-op on a host until it is installed.

.claude/tasks/0009-install-flow-docs.md

@@ -0,0 +1,36 @@
+---
+spec: laptop-mvi
+blocked-by: [0002-neogaia-disk-and-boot, 0003-kernel-and-hardware, 0004-networking-and-base-system, 0005-fish-shell-module, 0006-tmux-module, 0007-nvim-module, 0008-claude-code-module]
+---
+
+## What to build
+
+Document the one-shot install procedure that turns the completed `neogaia` `Host` into a running encrypted laptop from the NixOS live ISO — the capstone, written once every functional slice is in place so it describes the actually-complete `Host`.
+
+The procedure: push the repo to Gitea first; from the live ISO, join wifi, clone the repo locally (avoiding self-signed-TLS/auth problems with flake fetching during install), and run `disko-install` against the `neogaia` `Host` with the chaotic substituter passed to the install-time Nix daemon (or it compiles the CachyOS kernel from source on the USB stick). Then set the bootstrap password by hand via `nixos-enter` — never committed to the public repo — and reboot.
+
+Note the bootstrap ordering (the flake must exist on Gitea before the install can consume it) and that moving the password to a `hashedPasswordFile` backed by a sops secret is the first post-boot task, out of scope here (per ADR 0001, an age key does not exist until the first install generates the SSH host key).
+
+## Acceptance criteria
+
+- [x] The install procedure is documented end to end: push to Gitea → join wifi on the live ISO → clone locally → `disko-install` against `neogaia` → set bootstrap password via `nixos-enter` → reboot.
+- [x] The docs state that the install-time Nix daemon must have the chaotic substituter configured, or the kernel compiles from source on the USB stick.
+- [x] The docs explain that the local clone avoids self-signed-TLS/auth problems with flake fetching during install.
+- [x] The bootstrap password is set by hand and never committed; the docs flag the sops-backed `hashedPasswordFile` migration as the first post-boot follow-up.
+
+## Implementation Notes
+
+The runbook lives at `docs/install.md`.
+
+Every documented command was checked against the actual pinned tooling rather than written from memory:
+
+- The `disko-install` and `disko` flags (`--flake`, `--disk NAME DEVICE`, `--write-efi-boot-entries`, `--option`, `--mode mount`) were read out of the pinned disko revision's wrapped scripts (the disko rev in `flake.lock`).
+- A consequence surfaced there and shaped the doc: `disko-install` traps `EXIT` and **unmounts** the target, so the "set the bootstrap password" step must first remount with `disko --mode mount` before `nixos-enter`.
+  A naive `nixos-enter --root /mnt` straight after the install would have found nothing mounted.
+- The chaotic substituter URL and trusted key are quoted verbatim from `system/default.nix`, and `--disk main /dev/nvme0n1` matches `hosts/neogaia/disk.nix`.
+
+Two secrets are set by hand at install time, not one: the doc distinguishes the **LUKS passphrase** (prompted by disko at format, typed at every boot) from the **bootstrap login password** (set via `nixos-enter passwd`).
+The task named only the login password; the LUKS passphrase is an unavoidable part of the same by-hand flow, so it is documented alongside for a complete runbook.
+
+Beyond the task's terse list, the doc adds: a minimal-vs-graphical ISO split for joining wifi, and — from review — an SSH-key caveat for the clone plus an HTTPS-with-`sslVerify=false` fallback (which also reinforces the "git can skip verification where the flake fetcher can't" point behind the local-clone requirement).
+No criteria were dropped.

.claude/tasks/0010-sops-skeleton-and-password.md

@@ -0,0 +1,62 @@
+---
+spec: sops-secrets
+---
+
+## What to build
+
+The tracer bullet for encrypted secrets: a working two-tier age identity model, with the primary user's login password arriving as a decrypted secret rather than a value typed into a running machine.
+
+Establish the two identities the model rests on.
+An admin identity is generated and stored as a secure note in the operator's password manager; only its public recipient ever appears in the repo, and no copy of the private half is committed in any form.
+A host identity is generated on `neogaia` itself, onto its encrypted root, never transmitted, and deliberately not derived from the machine's SSH host key.
+
+Commit a sops configuration naming both recipients and a shared secrets file encrypted to admin plus `neogaia`, holding the primary user's password hash.
+The hash lives in the shared file rather than a per-host one because the same password is used on every machine, so per-host copies would only make rotation a multi-file edit.
+
+Wire the tooling into the flake as unconditional plumbing in the shared base config — not behind an enable flag, on the same grounds as the overlays and the flakes settings.
+The base config carries only the machinery: the flake input, the identity file location, and the default secrets file.
+The password secret itself is declared beside the user declaration it feeds, so a reader finds the secret where they find its use.
+
+The password secret must be marked as needed for user creation, which decrypts it in an earlier activation stage than ordinary secrets.
+That ordering is why the host identity has to sit on the root filesystem rather than anywhere mounted later.
+
+The transition is safe on `neogaia`: if activation fails the rebuild fails and the running generation persists with its existing hand-set password intact.
+
+## Acceptance criteria
+
+- [x] An admin age identity exists in the operator's password manager; its private half is committed nowhere, in no form
+- [x] A host age identity exists on `neogaia`'s encrypted root and was generated on the machine
+- [x] The sops configuration in the repo names the admin recipient and the `neogaia` recipient
+- [x] A shared secrets file, encrypted to admin plus `neogaia`, holds the primary user's password hash
+- [x] The secrets flake input is added, following the base nixpkgs
+- [x] The shared base config carries the machinery unconditionally — identity file location and default secrets file — with no enable flag
+- [x] The password secret is declared beside the user declaration, consumed through `hashedPasswordFile`, and marked as needed for user creation
+- [x] `nix flake check` builds the `neogaia` toplevel; a mistyped secret name or missing secrets file fails it
+- [x] Manual confirmation: `neogaia` activates, and console login succeeds against the decrypted password hash
+
+## Implementation Notes
+
+**`users.mutableUsers = false` was required and is not in the plan.**
+NixOS applies a declared password hash to an account that already exists in `/etc/shadow` only when `mutableUsers` is false — `update-users-groups.pl` guards both assignments on it.
+At the default of true, `alexion` already existed, so `hashedPasswordFile` would have been ignored and the hand-set password kept, silently.
+The final acceptance criterion would then have passed while proving nothing, because the login being tested would still have been the old one.
+
+Two consequences follow, neither sanctioned by the spec.
+`passwd` no longer works, so rotating the password means re-running `mkpasswd`, re-encrypting the shared file, and rebuilding.
+Root has no declared password and is therefore locked (`!`), which blocks direct root login and the systemd emergency shell's `sulogin` prompt.
+`sudo` from the wheel group is unaffected, and generation rollback or `init=/bin/sh` remains available for recovery.
+Leaving root locked was chosen over declaring a root password, on the grounds that the recovery paths that survive a locked root do not depend on `/etc/shadow` at all.
+This is worth folding back into the parent spec before the servers exist, where a locked root and no SSH key would be a harder corner.
+
+**The negative half of the build criterion was exercised, not assumed.**
+A mistyped secret name fails with `the key 'alexion-passwrd' cannot be found`.
+A missing secrets file fails with `Path 'secrets/absent.yaml' does not exist in Git repository`.
+Both were tested by temporary edits that were reverted.
+
+**Identity handling.**
+The admin identity was generated by the operator in a terminal outside this session, so no copy of its private half ever reached the agent or the repo.
+The host identity was generated on `neogaia` into `/var/lib/sops-nix/key.txt` (mode 0400, root) on the `@root` subvolume of the LUKS-encrypted `cryptroot`, and never transmitted.
+
+**Follow-up worth flagging for 0011.**
+`services.openssh.enable` is true on `neogaia` with no declared `authorizedKeys`, so SSH is not a fallback route in if a future decryption failure locks the console.
+The task that makes the SSH host keys secrets is the natural place to settle that.

.claude/tasks/0011-neogaia-ssh-host-keys.md

@@ -0,0 +1,60 @@
+---
+spec: sops-secrets
+blocked-by: 0010-sops-skeleton-and-password
+---
+
+## What to build
+
+`neogaia`'s SSH host keys become secrets, so reimaging the laptop no longer invalidates its host identity or breaks `known_hosts` for every client that has ever connected to it.
+
+Introduce a per-host secrets file for `neogaia`, encrypted to the admin identity plus `neogaia` alone — the first file in the repo that is not readable by the whole fleet, and the thing that keeps a compromised machine from decrypting another's material.
+The host's SSH **private** keys go in it.
+
+The host **public** keys are committed in plaintext.
+Publishing them is their function, and encrypting them would impose a re-key cycle every time one changes.
+
+Stop the SSH daemon generating its own host keys and point it at the decrypted paths instead.
+These secrets decrypt in the ordinary activation stage rather than the early pre-user one, so this slice exercises the second of the two decryption paths.
+
+## Acceptance criteria
+
+- [x] A secrets file for `neogaia` exists, encrypted to the admin identity and `neogaia` only — not to any other recipient
+- [x] `neogaia`'s SSH host private keys are stored in it
+- [x] The corresponding host public keys are committed in plaintext
+- [x] The SSH daemon no longer generates its own host keys and reads the decrypted paths
+- [x] The host key secrets are declared beside the SSH daemon configuration that consumes them
+- [x] `nix flake check` builds the `neogaia` toplevel
+- [x] Manual confirmation: after activation the secrets materialize with the declared ownership and mode, the daemon adopts the restored keys, and the host fingerprint presented to a client is unchanged
+
+## Implementation Notes
+
+**Both key types were preserved, not just ed25519.**
+The running daemon served an ed25519 and an RSA host key, and a client that pinned either would break if only one were carried over.
+Both private halves are in `secrets/neogaia.yaml`.
+
+**The decrypted keys stay at their default `/run/secrets/` paths.**
+The first attempt set each secret's `path` to the conventional `/etc/ssh/ssh_host_*_key`, which has sops plant a symlink inside a directory NixOS otherwise manages through `setup-etc`.
+It worked, but it buys nothing: `sshd` reads whatever `HostKey` names, and the extra `/etc` interaction depends on activation ordering that nothing in the config pins.
+The `HostKey` lines now interpolate `config.sops.secrets.<name>.path`, so the daemon and the secret cannot disagree about where the key is.
+`/etc/ssh` ends up holding no key material at all.
+
+**`restartUnits = [ "sshd.service" ]` is not in the plan and is needed.**
+`sshd` reads its host keys once at startup.
+Without this, re-keying the host would rewrite the decrypted files while the daemon kept serving the old keys from memory until some unrelated restart — silently, and precisely the identity drift this task exists to prevent.
+The plan's manual criterion would not have caught it, since it was verified on a switch where the keys had not changed.
+
+**The committed public keys have no consumer yet.**
+An intermediate version deployed them to `/etc/ssh` via `environment.etc`.
+That was dropped as scope the task did not ask for: `sshd` derives the public half from the private key at load, so nothing read them.
+They are committed, per the criterion, and the task that distributes `known_hosts` to clients is where they acquire a use.
+
+**Verification was stronger than a before/after comparison.**
+After activation the leftover `/etc/ssh/ssh_host_*_key` symlinks from the first attempt were removed and `sshd` restarted with no key material anywhere in `/etc/ssh`.
+It came back active and presented `SHA256:2ysuBX0+Z6GbdCTujz5JHX6rqnJzIyWhYNrxdhhGwEM` (ed25519) and `SHA256:y6Tl3P/FvfufblfG059BfCsSkMYX8Zk2EpFQvWzCAew` (RSA) — identical to the pre-change fingerprints.
+The generated `sshd-keygen.service` has no `ExecStart` at all, which is what confirms generation is off rather than merely idle.
+Separately, the encrypted file was decrypted with the host identity and diffed against the live private keys before anything was changed.
+
+**Task 0010's handoff about `authorizedKeys` is deliberately left open.**
+That note proposed settling it here, on the grounds that SSH is not a recovery route while no key is authorized.
+It is not an acceptance criterion of this task, and choosing which public key to trust is the operator's call rather than one to infer.
+It wants its own task, and remains a real gap: a decryption failure that locks the console still has no network fallback.

.claude/tasks/0012-secrets-operations-docs.md

@@ -0,0 +1,68 @@
+---
+spec: sops-secrets
+blocked-by: [0010-sops-skeleton-and-password, 0011-neogaia-ssh-host-keys]
+---
+
+## What to build
+
+A thorough revision of the install document, not an appendix to it.
+
+The existing procedure is built around a login password set by hand through `nixos-enter` after the install and never committed.
+That step no longer exists, so the parts of the document that describe it are wrong rather than merely incomplete: the framing that names two hand-entered secrets, the step that sets the bootstrap password, the reboot step's instruction to log in with it, and the closing follow-up section — which additionally describes the superseded key-derivation mechanism as the reason sops wiring cannot happen during an install.
+The LUKS passphrase remains the one secret genuinely entered by hand, and the revised document should say so plainly.
+
+The install ordering inverts.
+A host's identity is now provisioned and registered *before* its first boot, because the login password arrives only from a decrypted secret and there is no fallback credential — a first boot without a registered identity has no way in.
+The document should carry that as the reason, since it is the whole point of the reordering.
+
+Cover four procedures:
+
+- Provisioning a host that is already installed and running, done live on the machine: generate the identity, add its recipient, re-key the affected files with the admin identity, rebuild. No reimage, no live ISO.
+- Provisioning a host that does not yet exist, done on the live ISO before the install: generate the identity, add its recipient, re-key, write the identity onto the target root, then install. The install builds from a local clone, so no push is required mid-procedure; the recipient change is committed afterward.
+- The editing workflow: which secrets the workstation can change on its own, and which require unlocking the admin identity for the session. That friction is intended, not an oversight.
+- Recovery from a live ISO for a machine whose identity was provisioned wrongly, so a failed first boot is a known procedure rather than an improvised one.
+
+Everything goes in the existing install document; no new document is introduced.
+
+## Acceptance criteria
+
+- [x] No step remains that sets a login password by hand, and nothing instructs the operator to log in with one
+- [x] The document's framing names the LUKS passphrase as the only hand-entered secret
+- [x] The install ordering places identity provisioning before first boot, and states why there is no fallback credential
+- [x] The closing section no longer describes deriving identities from SSH host keys or defers sops wiring to a post-boot follow-up
+- [x] Live provisioning for an already-running host is documented
+- [x] Pre-install provisioning on the live ISO for a not-yet-existing host is documented, including that the recipient change is committed after the install
+- [x] The editing workflow is documented, distinguishing what the workstation can re-key alone from what needs the admin identity
+- [x] The live-ISO recovery path for a wrongly-provisioned machine is documented
+- [x] The document reads end to end as one coherent procedure for a reader who has never seen the previous version
+
+## Implementation Notes
+
+**The document was retitled and given a table of contents.**
+Three of the four procedures are not installs, so "Installing `neogaia`" no longer described the contents.
+It is now "Installing and provisioning a host", and the install procedure is one section among four rather than the whole document.
+The install steps stay concrete about `neogaia` and its NVMe device, since that is the only machine the flake installs today and a generic example would be less useful than a real one.
+
+**Commands were verified against the running system rather than written from memory.**
+Neither `sops` nor `age` is packaged by this flake, so every invocation goes through `nix run nixpkgs#sops` or `nix shell nixpkgs#age -c age-keygen`, and the document says so up front.
+`sops updatekeys`, `age-keygen -y`, and `nixos-install --root/--flake/--no-root-password` were each confirmed to exist.
+The identity file's `0400 root:root` and `/var/lib/sops-nix/key.txt` were read off the live machine, and `/var` was confirmed to sit on the `@root` subvolume, which is what makes the path valid before user creation.
+
+**Review caught four factual errors, all corrected.**
+The most consequential: the post-provisioning check said `ls -l /run/secrets/`, but `neededForUsers` puts the password hash in `/run/secrets-for-users/` — confirmed by `nix eval`, which returns `/run/secrets-for-users/alexion-password`.
+The one secret whose failure causes the lockout the document exists to prevent was the one the reader was told not to look at.
+Also fixed: the `.sops.yaml` example added a new host to the shared rule but not a rule for its own file, which makes `sops` refuse it with `no matching creation rules found`; step 8's `updatekeys` omitted `SOPS_AGE_KEY_FILE`, so it would have looked in `~/.config/sops/age/keys.txt` rather than the root-owned identity; and "create its file now" did not say that a host enabling the SSH daemon needs `ssh-host-<type>-key` entries or the build fails at evaluation.
+
+**Deliberate redundancy in the recovery path.**
+Review flagged the disko remount block and the re-key sequence as duplicated between the install and recovery sections.
+They are left duplicated on purpose: an operator running the recovery procedure is locked out of the machine, and sending them to page back into the install steps mid-recovery is worse than the maintenance cost of two copies.
+The already-running-host procedure does cross-reference step 4, because that reader has a working machine and can follow a link.
+
+**The recovery procedure is documented but unexercised.**
+Both branches follow from verified facts — `nixos-install` is idempotent and reuses the formatted disk, and the secrets file is baked into the closure at build time, which is why one branch needs a rebuild and the other does not.
+Neither has been run, because doing so requires deliberately locking out the only machine.
+The claim that no fallback credential exists was checked rather than assumed: there is no `authorizedKeys`, no root password, and `mutableUsers = false`.
+
+**Follow-up.**
+Task 0019 adds user SSH keys, which will make "no authorized SSH key" in the no-fallback paragraph stale.
+That paragraph is the place to revisit when it lands, since an authorized key would become a genuine second way in.

.claude/tasks/0013-nixos-hardware-profile.md

@@ -0,0 +1,40 @@
+## What to build
+
+Hand ownership of `neogaia`'s hardware facts to the upstream `nixos-hardware` profile for the Dell XPS 13 9380, replacing settings this repo currently guesses or omits.
+
+The profile is adopted wholesale, including the Intel GPU support it pulls in. Those packages are inert on a machine with no display server, and trimming them would mean diverging from upstream for no present benefit.
+
+Adopting it makes four things true that are false on the running machine today: the laptop suspends into deep S3 rather than s2idle, the redundant PS/2 mouse driver stops loading over the i2c touchpad, thermal management runs, and firmware updates become possible.
+
+The microcode setting the `Host` currently declares is dropped, because the profile provides it as a default keyed off the redistributable firmware setting already enabled here.
+
+## Acceptance criteria
+
+- [x] `nixos-hardware` is a flake input
+- [x] The Dell XPS 13 9380 profile is imported by the `neogaia` `Host`
+- [x] The `Host`'s own Intel microcode setting is removed, now that the profile supplies it
+- [x] `nix flake check` builds the `neogaia` toplevel
+- [x] Manual confirmation after a rebuild: the default sleep mode is deep rather than s2idle
+- [x] Manual confirmation after a rebuild: the thermal and power management services are active, and the PS/2 mouse driver is no longer loaded
+
+## Implementation Notes
+
+Both manual criteria were confirmed on the rebooted machine. The selected sleep
+mode moved from s2idle to deep, with the kernel parameter visible on the boot
+command line; the thermal and power management services came up active; and the
+PS/2 mouse module is no longer loaded. The booted system, the running system and
+the freshly built toplevel are all the same store path, so these readings come
+from this configuration rather than a surviving older generation.
+
+The firmware update service reads as inactive, which is correct rather than a
+failure: it is activated on demand over D-Bus. Its unit is present, its refresh
+timer is enabled, and its command-line tool is on the path.
+
+The input follows the base nixpkgs. Locking it without that pulled a second
+nixpkgs into the lock file, which nothing evaluates — only the NixOS modules are
+consumed — and which would drift silently. Following matches every other input
+here except chaotic, whose separate pin is deliberate.
+
+Intel microcode updates now rest on the profile's default rather than an explicit
+setting here. The default is overridable, so a `Host` that disables redistributable
+firmware would silently lose microcode updates too.

.claude/tasks/0014-nix-store-housekeeping.md

@@ -0,0 +1,30 @@
+## What to build
+
+Bound the three things on this machine that currently grow without any limit: the Nix store, the set of retained system generations, and the boot menu.
+
+Garbage collection runs weekly, deleting generations older than 30 days. That window is the point of the setting — on a rolling channel with a third-party kernel, the value of an old generation is having a known-good system to boot when an update breaks something, and disk space is not scarce here: the store is under 5 GiB against 473 GiB free.
+
+Store optimisation runs weekly on its own schedule rather than at build time, so deduplication never adds latency to a rebuild.
+
+Retained boot configurations are capped at 15. Each generation stores a kernel and an initrd on the EFI system partition at roughly 70 MiB apiece, and that partition is small and fixed. An exhausted one fails at bootloader installation — after the build has already succeeded, which is a confusing place to get stuck. The cap assumes the enlarged partition; on the current 512 MiB one only about seven fit.
+
+## Acceptance criteria
+
+- [x] Automatic garbage collection is enabled weekly, deleting generations older than 30 days
+- [x] Store optimisation is scheduled weekly, rather than performed at build time
+- [x] Retained boot configurations are capped at 15
+- [x] These are declared as plumbing in the shared base config, so every future `Host` inherits them
+- [x] `nix flake check` builds the `neogaia` toplevel
+- [x] Manual confirmation after a rebuild: the collection and optimisation timers exist and are scheduled
+
+## Implementation Notes
+
+The two schedules are named days rather than the bare `weekly` keyword.
+systemd expands `weekly` to `Mon *-*-* 00:00:00`, which would have started collection and deduplication at the same instant every week, leaving `nix-optimise` hard-linking paths `nix-gc` was concurrently deleting.
+Collection now runs `Mon 03:15` and optimisation `Thu 03:45`, which keeps both weekly and keeps them apart.
+
+The boot configuration cap sits in the shared base as the task asks, and is inert rather than an error on a host that does not use systemd-boot.
+A future host on another bootloader therefore inherits no cap, which is the one place the "every future host inherits them" promise does not reach.
+
+Confirmed on `neogaia` after a switch: `systemctl list-timers 'nix-*'` lists both units, `nix-optimise` next on Thursday and `nix-gc` next on Monday, each `Persistent=true` so a suspended laptop catches up on a missed firing.
+`/boot` reports 2 GiB with 113 MiB used, so the cap of 15 sits against the enlarged partition it assumes.

.claude/tasks/0015-git-module.md

@@ -0,0 +1,42 @@
+## What to build
+
+A git `Module`, following the `Enable convention` and configured natively through home-manager, that carries the operator's commit identity — enabled on `neogaia`.
+
+Today that identity exists only in one repository's local configuration on one machine. It is therefore invisible to every other checkout, absent from any future `Host`, and lost on a reimage. Declaring it makes committing work anywhere, reproducibly, like everything else in the flake.
+
+The identity matches the one already present throughout this repository's history, so existing commits and future ones agree. Committing it is not a disclosure: it appears in every commit this repository has ever published.
+
+It is a `Module` rather than base plumbing because a `Host` that should not carry a personal commit identity is easy to imagine once the servers exist.
+
+## Acceptance criteria
+
+- [x] A git `Module` following the `Enable convention` exists and is enabled on `neogaia`
+- [x] The commit identity is configured through home-manager and matches the one used in existing history
+- [x] `nix flake check` builds the `neogaia` toplevel
+- [x] Manual confirmation: committing in a repository outside this checkout succeeds with no per-command identity override
+- [x] The stale note in the project's agent instructions claiming git identity is unconfigured is corrected, since commits already work here through repository-local configuration
+
+## Implementation Notes
+
+`programs.git.userName`/`userEmail` are renamed in this home-manager pin and emit an obsolete-option trace.
+The module uses `settings.user.name`/`settings.user.email`.
+Do not "fix" it back.
+
+Review on the pull request asked for the module on every host, which was first built by defaulting `enable` to true and dropping the per-host line.
+The operator then chose the opposite: `enable` defaults to false and each host enables it explicitly, so a host keeps reading as a full checklist of what it carries rather than hiding a default-on module.
+Enabling it is therefore a step when adding a host.
+
+The commit name is the literal `"alexion"` rather than `config.user.name`, which review raised as duplication.
+A Unix login and a commit display name are separate concepts that merely coincide here, so binding them would let a host overriding its login silently rewrite the operator's commit identity.
+
+The manual confirmation is met on the running machine.
+The operator rebuilt `neogaia`, `~/.config/git/config` is now a home-manager symlink, and a commit in a repository outside this checkout was authored `alexion <contact@alexion.dev>` in the real environment with no per-command override and no identity in the test repository's own config.
+
+Review surfaced an unanticipated hazard that proved harmless.
+Home-manager writes `~/.config/git/config`, while an undeclared `~/.gitconfig` also exists and outranks it on any key set in both.
+It holds only a `tea` credential helper and no `user.*`, so it does not shadow the identity, confirmed against the deployed configuration.
+Declaring that credential helper is a reasonable follow-up, since it will not survive a reimage.
+
+This checkout's `.git/config` still sets the same identity, now redundant.
+Removing it would let the module govern here too, so a future breakage surfaces instead of being masked.
+It is local, untracked state, so it is left alone rather than changed as part of this task.

.claude/tasks/0016-esp-resize-and-reimage.md

@@ -0,0 +1,59 @@
+---
+blocked-by: 0013-nixos-hardware-profile
+---
+
+## What to build
+
+Grow `neogaia`'s EFI system partition and reimage the laptop from the finished configuration.
+
+The partition is 512 MiB today, holding about seven generations at roughly 70 MiB of kernel and initrd apiece, and this `Host` runs a large third-party kernel. It grows to 2 GiB, which holds around 28 — comfortably past the 15 that are retained, at a cost of 0.3% of a 512 GB disk.
+
+It cannot be grown in place: it sits first on the disk, starting at sector 2048 with the encrypted container immediately behind it, so enlarging it means moving that container's start offset. An encrypted volume's start cannot be relocated without rewriting its entire payload, which here is over 500 GiB. A reimage is the only practical route, and it is cheapest now — the machine is days old and holds around 3 GiB, of which 136 MiB is user data.
+
+The hardware profile blocks this because it is the one boot-affecting change queued: it adds a kernel parameter and blacklists a module. Proving it boots while a known-good generation still exists to roll back to means the reimage installs a configuration already known to work on this hardware. A freshly imaged machine has one generation and no rollback target, which is the wrong place to discover a bad kernel parameter.
+
+Nothing else blocks it. The housekeeping and commit-identity changes carry no boot risk and apply in seconds on either side of the wipe, so they must not be allowed to delay it — the case for reimaging now rests on the machine still holding almost nothing, and that erodes with every day of use.
+
+This reimage is also the reproducibility test of the install documentation. The first install was performed while writing it; performing it a second time against the current configuration is what proves it is a procedure rather than a record of one improvised session.
+
+One thing must be true before the disk is erased: every branch worth keeping has to exist on the remote, because work that lives only on this disk dies with it.
+
+## Acceptance criteria
+
+- [x] The `Host`'s disk layout declares a 2 GiB EFI system partition
+- [x] Every local branch worth keeping exists on the remote before the disk is erased
+- [x] The reimage is performed from a configuration carrying the hardware profile, following the existing install documentation
+- [x] The install documentation is corrected wherever the procedure diverged from what it describes
+- [x] Manual confirmation: the machine boots, the encrypted root unlocks, and console login succeeds
+- [x] Manual confirmation: reported free space on the boot partition is consistent with its 2 GiB size, resolving the discrepancy observed before the reimage — where a 512 MiB partition reported 1022 MiB
+- [x] The project's agent instructions record that a flake only sees git-tracked files, so an untracked file is invisible to evaluation
+
+## Implementation Notes
+
+Done. The reimage was performed by the operator and the machine now runs the
+configuration this repository declares.
+
+The install ran clean: the operator reports no step diverged from
+`docs/install.md`, so criterion 4 is satisfied with no further corrections. The
+four corrections that landed earlier came from reading the procedure; the run
+itself found nothing to add. That is the reproducibility evidence the task was
+after — the document is a procedure, not a record of one improvised session.
+
+Verified on the running machine rather than assumed:
+
+- `/dev/nvme0n1p1` is 2.0 GiB and `df` reports 2.0 GiB. The pre-reimage
+  discrepancy, where a 512 MiB partition reported 1022 MiB, is gone.
+- The hardware profile is live — `mem_sleep_default=deep` is on the kernel
+  command line and `psmouse` is blacklisted and not loaded.
+- `cryptroot` is open on `nvme0n1p2` with btrfs mounted, reached through a
+  console login, so the boot-unlock-login path is exercised end to end.
+- One generation exists (`system-1-link`), confirming a fresh install rather
+  than a rebuild of the prior system.
+
+The ordering hazard closed favourably: the declaration and the install landed
+close enough together that the repository never asserted a layout the disk
+lacked for long.
+
+Two items outside the repo did not survive the wipe, as anticipated, and neither
+is covered by a criterion: the wifi credentials, and the agent memory directory
+— confirmed empty after the reimage.

.claude/tasks/0017-hardware-detection-refresh.md

@@ -0,0 +1,40 @@
+---
+blocked-by: 0016-esp-resize-and-reimage
+---
+
+## What to build
+
+Replace `neogaia`'s hand-written hardware detection file with a real scan of the machine it describes.
+
+The file was written before the laptop ran NixOS, as an educated guess at what a Dell XPS 13 9380 needs, and still says so. The guess turned out to be adequate — the module required to reach the encrypted root is present and working — so this is honesty maintenance rather than a fix. It matters because the next person to read the file, including a future reader of this repo, should be able to trust that it describes measured hardware.
+
+Only the detection results are kept: the modules the initrd needs, the modules the kernel loads, and the platform. The generated output also contains filesystem and swap declarations, which are dropped — the declarative disk layout owns those, produces them on every evaluation, and a second stale definition would either conflict outright or silently disagree.
+
+Generating the scan requires root on the target machine.
+
+## Acceptance criteria
+
+- [x] The detection file's contents come from a scan of the running machine rather than a guess
+- [x] Filesystem and swap declarations are absent from it, leaving the disk layout as the sole source of those
+- [x] The file no longer describes itself as a placeholder, and says plainly what it holds
+- [x] `nix flake check` builds the `neogaia` toplevel
+
+## Implementation Notes
+
+**The guess was wider than the measurement, not narrower.**
+It named `thunderbolt`, `usb_storage`, and `sd_mod`, none of which the scan reports; the scan adds `rtsx_pci_sdmmc` for the card reader.
+Nothing needed to reach the root device was missing, so the guess was adequate as the task assumed, but it was not accurate.
+`sd_mod` survives in the resolved list regardless, supplied by nixpkgs' own defaults; `thunderbolt` and `usb_storage` now genuinely go, and they matter only for booting from external media, which this machine does not do.
+
+**Two further lines from the scan were dropped beyond the filesystem and swap declarations the task named.**
+`boot.initrd.luks.devices."cryptroot".device` is derived by the disk layout, which the layout file already states, so keeping it would have created the same duplicate definition the task drops the filesystems to avoid.
+`hardware.cpu.intel.updateMicrocode` falls outside the three things the task keeps, and the hardware profile supplies it anyway.
+Both were checked rather than assumed: after the change the LUKS device, all four filesystems, and microcode all still resolve.
+
+**The header was rewritten twice.**
+Its first form enumerated the file's three attributes, which the repo's comment convention names as a feature inventory and forbids in a file-top header.
+It now carries provenance and the absence pointer only.
+
+**Verified by a boot.**
+`nix flake check` proves only that the configuration evaluates and builds, so the reduced initrd was exercised on the machine: it unlocked LUKS and mounted the btrfs root unaided.
+The running system's store path matches this configuration's build exactly, confirming the boot used it rather than an earlier generation.

.claude/tasks/0018-agent-sudo-credential-caching.md

@@ -0,0 +1,64 @@
+## What to build
+
+Make root-requiring work reachable from an agent session without waiving the password, by sharing sudo's credential cache across sessions and failing loudly when it is cold.
+
+Sudo caches an authentication for a timeout window, but keys that cache by terminal under its default `timestamp_type=tty`.
+An agent's commands run in subprocesses on a different terminal, so a `sudo -v` typed in the operator's shell is invisible to them and every privileged command fails.
+Setting `timestamp_type=global` keys the cache per user instead, so one authentication covers the whole machine for the window.
+The timeout is raised to 60 minutes so a session needing root authenticates once rather than every five.
+
+No `NOPASSWD` rule is introduced, and this is the point of the design.
+The password remains genuinely required; only its cache is shared.
+A `NOPASSWD` entry for `nixos-rebuild` would be indistinguishable from blanket root on this machine, since anything able to edit the flake and then rebuild it owns the system.
+
+The tradeoff is real and bounded: during the window, any process running as the operator can use the cached credential, not only the agent.
+That is acceptable on a single-user personal laptop where the agent already runs as that user, and it is the reason this belongs to a laptop rather than to any future server `Host`.
+
+The second half is failure behaviour.
+A cold cache today surfaces as a bare non-zero exit with no output, which reads as an unexplained stall: the operator has to notice the agent is stuck and then work out what it wanted.
+A `PreToolUse` hook probing `sudo -n true` turns that into an immediate, actionable refusal naming the command to run.
+
+## Acceptance criteria
+
+- [-] `timestamp_type=global` and a 60-minute timeout are declared as plumbing in the shared base config
+- [x] No `NOPASSWD` rule is introduced, and the wheel group still requires a password
+- [x] Confirmed that NixOS does not already set `timestamp_type` elsewhere, so the declaration is not silently overridden
+- [x] A `PreToolUse` hook in the claude-code `Module` denies a privileged command when the cache is cold, naming `sudo -v` in its message
+- [x] The hook's behaviour is correct when the harness sandbox, rather than a cold cache, is what blocks the command
+- [x] `nix flake check` builds the `neogaia` toplevel
+- [x] Manual confirmation after a rebuild: `sudo -v` in one terminal lets a privileged command succeed from an agent session, and that command fails with the hook's message once the window lapses
+
+## Implementation Notes
+
+**The sudo settings are declared in the claude-code module, not in the shared base config.**
+The criterion asking for the shared base contradicted this task's own rationale, which argues the widened cache suits a single-user machine and should not reach a future server.
+Neither placement was right, though: the setting and the hook that depends on it belong together.
+The hook reads the credential cache from a process of its own, which only works under `timestamp_type=global`, so a host enabling the module without the sudo half would get a hook that never sees a cached credential and refuses every privileged command permanently.
+Declaring both under the module's `enable` makes that impossible to get wrong, and carries the setting to any future host that runs the agent.
+
+The cost is that enabling a developer tool now changes the machine's sudo posture, which a reader auditing sudo policy would not expect to find there.
+The enable option's description carries the warning so it surfaces in generated documentation.
+Should a host ever need the agent without the widened cache, that is when a separate sub-option earns its place; adding one now would be speculative.
+
+**Verified against the running system, in both cache states.**
+Cold, the hook refuses with its message; warm, it permits and the command uses a credential authenticated in a different terminal.
+The hook process is not itself sandboxed, so it reads the real cache rather than refusing unconditionally — the failure mode that would have required it to fail open instead.
+
+One residual is worth knowing.
+The hook governs whether a privileged command is attempted, not whether it can run: the agent's own sandbox blocks `sudo` separately, and swallows it into a bare exit with no output.
+A permitted command can therefore still fail for that unrelated reason, and needs the sandbox disabled.
+The two are distinguishable in practice, since only one of them produces the hook's message.
+
+**The operator must authenticate from a real terminal.**
+Warming the cache from inside an agent session does not work: that shell has no controlling terminal, so sudo cannot prompt and reports `a terminal is required to read the password`.
+Feeding the password by another route was rejected rather than unexplored.
+Reading it from the agent's stdin would route it through the agent, and an askpass helper on this console-only machine could only prompt on the pane the agent already draws to, which trains the operator to type a password into an agent-controlled surface.
+A separate terminal is the only safe channel, which is precisely what the global cache keying exists to make useful.
+
+**`jq` is now a home package.**
+The hook parses the tool input handed to it on stdin, and nothing on the profile provided a JSON parser.
+Matching on the raw JSON text with `grep` was rejected: a command containing quotes or newlines would break it, and this hook fails closed, so a parsing mistake blocks real work.
+
+**The sudo detection is anchored to command position.**
+`grep sudo /etc/passwd` and `echo "run sudo -v"` are allowed; `sudo x`, `cd /tmp && sudo x`, and `true; sudo x` are blocked.
+A `sudo` inside a quoted string that happens to sit in command position will still trip the guard, which errs toward asking rather than stalling.

.claude/tasks/0019-user-ssh-keys-and-access-policy.md

@@ -0,0 +1,87 @@
+---
+blocked-by: 0011-neogaia-ssh-host-keys
+---
+
+## What to build
+
+The operator's SSH client key becomes a secret, and which machines may reach which becomes a declared policy rather than a hand-edited list.
+
+Today the key that authenticates pushes to the remote exists only as a file created by hand on one laptop.
+It is in no secrets file and no module, so a reimage destroys it.
+That is worse than losing a host key: a lost host key makes clients complain about `known_hosts`, whereas a lost client key locks the operator out of the remote until a new one is generated and registered through the forge's web interface.
+
+Each machine gets its **own** client identity rather than one shared across the fleet.
+The private half lives in that machine's own secrets file, so it is readable by that machine and the admin identity alone.
+A compromised machine therefore surrenders only its own key, and withdrawing a machine's access means removing one public key rather than re-keying every other machine.
+The public halves are committed in plaintext, as the host public keys are, since publishing them is their function.
+
+The private half decrypts at activation and is readable only by the primary user.
+Following the host keys, the client is pointed at the decrypted path rather than having a copy written into the user's home, so there is one authoritative location for the key and no copy to drift.
+
+Access is expressed as a policy over machine roles, not as a per-host list of authorized keys.
+A **workstation** may reach every machine in the fleet.
+A **server** may reach other servers only.
+Consequently every machine authorizes the workstation keys, and servers additionally authorize the server keys, while a workstation never authorizes a server's key — so a compromised server cannot reach the operator's own machines.
+
+This wants a single declaration of the fleet, naming each machine's role and its client public key, from which every host derives the set it authorizes.
+Registering a new machine is then declaring its role in one place, rather than an edit to every other host's configuration.
+
+Only `neogaia` exists today, so the server half of the policy has nothing to act on and cannot be exercised.
+It is built and recorded now so that the desktop and the three planned servers are a role declaration rather than a redesign.
+
+Adopt the key already present on `neogaia` rather than generating a fresh one.
+It is already registered with the remote, so adopting it keeps pushes working, whereas replacing it would require registering the new key through the web interface before the old one stops being used — an ordering that locks the operator out if it goes wrong.
+Machines that do not exist yet generate their own key during provisioning, alongside the age identity.
+
+This also settles the gap left open by task 0010, where the daemon accepts connections but authorizes no key, so a failed decryption that locks the console has no network fallback.
+Note that the fallback only becomes real once a second machine exists to connect from.
+
+## Acceptance criteria
+
+- [x] `neogaia` has its own client SSH identity, distinct from its host keys, adopted from the key already on the machine
+- [x] Its private half is stored in `neogaia`'s own secrets file, encrypted to the admin identity and `neogaia` alone
+- [x] Its public half is committed in plaintext
+- [x] The private half decrypts at activation, readable only by the primary user and not by other accounts
+- [x] The SSH client uses the decrypted key with no hand-placed copy in the user's home directory
+- [x] Each machine declares a role, and the keys it authorizes follow from that role rather than from a per-host list
+- [x] Workstation keys are authorized on every machine
+- [x] Server keys are authorized on servers only, and on no workstation
+- [x] Registering a new machine is a role declaration in one place, requiring no edit to any other host
+- [x] `nix flake check` builds the `neogaia` toplevel
+- [x] Manual confirmation: the key materializes with the declared ownership and mode, an authenticated push to the remote still succeeds, and `neogaia` accepts an SSH connection offering the adopted key
+
+## Implementation Notes
+
+The whole policy is three options on the ssh module.
+Two are the lists of client public keys, one for the machines the operator works from and one for the machines that serve.
+The third is the set a machine admits, which a host declares in its own file by naming the lists it draws from.
+
+Two earlier designs were discarded as more machinery than the problem has.
+The first was a separate fleet declaration mapping each machine to a role and a key, which the module looked up by hostname.
+The second kept the two lists but derived the admitted set from a role enum.
+Authorizing a key needs the key text and nothing else, so the per-machine names, the hostname lookup and the role all existed to reconstruct a grouping that the two lists simply are.
+A host now states what it admits rather than stating a category that something else maps to keys.
+
+`authorizedKeys` defaults to the workstation keys.
+An option of a list type is not required in the way a scalar one is: leaving it undeclared yields the empty list rather than an evaluation error, and a machine admitting no key is unreachable over SSH.
+The default makes the safe case the silent one.
+
+Only `neogaia` exists, so the server half has nothing to act on.
+It was verified by temporarily adding a synthetic server key and declaring both lists on the host, then reverting.
+A host drawing on the workstation keys alone excluded the server key, and one drawing on both admitted it.
+Omitting the declaration entirely was confirmed to fall back to the workstation keys rather than to none.
+
+Home-manager's `matchBlocks` is deprecated in favour of `settings`, so the client uses the latter.
+`enableDefaultConfig = false` drops home-manager's own default directives, leaving the generated `~/.ssh/config` at two lines and every other directive at the value OpenSSH itself ships.
+
+The committed public key carries the comment `alexion@neogaia` rather than the adopted key's own `contact@alexion.dev`, so the list says which machine each key belongs to.
+An authorized-keys comment is free text and independent of the private key.
+
+Manual confirmation was performed after a `nixos-rebuild switch`.
+The secret materialized as `-r--------` owned by the primary user, and the public half derived from it matches the committed fleet entry.
+The hand-placed `~/.ssh/id_ed25519` was moved aside for the test, so both directions were exercised against the decrypted secret alone: `ssh -v` to the remote reported `Server accepts key: /run/secrets/ssh-user-ed25519-key`, and an inbound connection to `neogaia` authenticated and returned a shell.
+
+One follow-up is outstanding.
+Deleting the now-redundant `~/.ssh/id_ed25519` and its public half was refused by the agent's permission layer, so both files remain on the machine.
+They are superseded rather than needed: the same key is in `secrets/neogaia.yaml`, and the client is pointed at the decrypted path.
+Removing them is a one-line manual step, and the key is recoverable from the secrets file if it is ever wanted back.

.claude/tasks/0020-pi-coding-agent-module.md

@@ -0,0 +1,27 @@
+---
+spec: pi-coding-agent
+---
+
+## What to build
+
+Add a `pi` module, auto-discovered like every other feature and inert until a host enables it, that installs Pi for the primary user through the home-manager `programs.pi-coding-agent` module.
+On enable it freezes exactly one file — `settings.json` — pinning the default provider to Anthropic and the default model to Opus (the exact model-id string confirmed against Pi's own model catalogue), and disabling analytics.
+Everything else — agent context, skills, extensions, keybindings, custom providers — is left at its default, so home-manager renders nothing but `settings.json` and Pi owns the rest of `~/.pi/agent/`.
+Pi authenticates by reusing the existing Claude subscription, and that credential is left unmanaged by the flake so no secret enters the repo and re-auth survives rebuilds, mirroring how the `claude-code` module treats its login.
+Lay the module out as a directory (not a single file), and enable it on `neogaia` alone with a single `enable = true`.
+
+## Acceptance criteria
+
+- [x] A `pi` module exists as its own directory, declares a single `enable` option under the `modules` tree, guards its body with the Enable convention, and stays inert until a host enables it.
+- [x] On enable, the module turns on `programs.pi-coding-agent` for the primary user from the base package set, with no other host affected.
+- [x] The frozen `settings.json` sets the default provider to Anthropic, the default model to Opus (exact model-id verified against Pi's catalogue), and disables analytics — and no other upstream option (`context`, `models`, `keybindings`, `extraPackages`, `configDir`) is set.
+- [x] Pi's credential and all of its writable state (`~/.pi/agent/` beyond `settings.json`) are left unmanaged by the flake.
+- [x] `neogaia` enables the module with a single `enable = true` and its system toplevel still builds via `nix flake check` (the `checks.x86_64-linux.neogaia` target).
+- [x] Disabling the module is a one-line `enable` flip that leaves no flake-managed residue.
+
+## Implementation Notes
+
+- **Model-id and analytics key confirmed against Pi 0.80.7 at build time.** The `pi-coding-agent` package pins `0.80.7`; its `dist/core/model-resolver.js` defaults the `anthropic` provider to `claude-opus-4-8`, which is the Opus id used. The analytics key is `enableAnalytics` (boolean, default `false`), per the package's own `docs/settings.md`. Both were read from the built store path, not guessed.
+- **Verified through the primary seam.** `config.modules.pi.enable` and `programs.pi-coding-agent.enable` both evaluate `true` on `neogaia`; the rendered `settings.json` is exactly `{"defaultModel":"claude-opus-4-8","defaultProvider":"anthropic","enableAnalytics":false}`; only one file (`settings.json`) is rendered under `~/.pi/agent`; and `checks.x86_64-linux.neogaia` builds green with `pi-coding-agent-0.80.7` included.
+- **No deviations from the spec.** The diff is the module plus one `enable = true` line — every "Out of Scope" item (agent context/`AGENTS.md`, skills, extensions, keybindings, custom providers, Pi-specific sudo guard) is left out.
+- **Review follow-through.** `/review-uncommitted` rated Risk **Low** and Spec **clean**. Standards flagged four comment-convention issues on the new module (a semicolon in a comment, an overloaded file-top header duplicating the inline rationale, and a cross-file clause on the model-id comment); all were fixed in the diff, so the header is now a two-sentence purpose line mirroring the sibling `claude-code` module and the frozen-settings rationale lives only at its inline site. No findings left unaddressed.

.envrc

@@ -1 +0,0 @@
-use flake

.gitignore

@@ -1,8 +1 @@
 /reference/
-/.direnv/
-
-# BEGIN mkSkillsShellHook
-# Generated by mkSkillsShellHook. Nix-delivered skill symlinks, kept out of git.
-.claude/skills
-.agents/skills/gitea-axi
-# END mkSkillsShellHook

.sops.yaml

@@ -7,7 +7,6 @@ keys:
   - &admin age1m0pk94ysjlw3lmf6pyuv5l5pepvdjss8w0vxjv90dq6ndp02tdgsdwdvue
   # Generated on the machine it names.
   - &neogaia age14a04vphzjq74epfrz9a09wjw8lzchtru84awzuq2n45d8f42ychqjs89qe
-  - &pikachu age1wf5s0n0tgt6ld2ysgu9dc67mj8ylwecgl4utzg7hqwy3kut9zyms7aglmh
 
 creation_rules:
   # Material belonging to one machine.
@@ -19,16 +18,9 @@ creation_rules:
           - *admin
           - *neogaia
 
-  - path_regex: secrets/pikachu\.yaml$
-    key_groups:
-      - age:
-          - *admin
-          - *pikachu
-
   # Material common to every machine, so it is stored once rather than per host.
   - path_regex: secrets/shared\.yaml$
     key_groups:
       - age:
           - *admin
           - *neogaia
-          - *pikachu

AGENTS.md

@@ -1,110 +0,0 @@
-# dotfiles-nixos
-
-One flake builds every machine I own.
-
-## Repository Conventions
-
-- Use `docs/technical-writing.md` and `docs/dictionary.md` while authoring any file.
-  Apply them to comments, user-facing descriptions, commit prose, pull-request prose, and Markdown documentation.
-- Comments posted to the forge under the operator's account must end with `— Pi`.
-  The sign-off identifies the agent as the author instead of the operator.
-- Commit messages follow Conventional Commits, defined in `docs/conventional-commits.md`.
-  Use a scope for the changed module or host, such as `fish`, `nvim`, or `neogaia`.
-- Keep commit messages about the Git history, not the forge workflow.
-  Do not reference issue or pull-request numbers unless the commit itself requires a stable external reference.
-- During pull-request development, add follow-up commits instead of amending existing commits.
-  Preserve review history until the pull request is ready to merge.
-- Use `gitea-axi` for Gitea issues, pull requests, labels, reviews, comments, and milestones.
-  It resolves this repository from the `origin` remote inside the checkout.
-
-## Dotfiles Conventions
-
-### Desktop
-
-- When adding a graphical application, add a `window-rewrite` icon mapping in `modules/desktop/session/waybar.nix`.
-  The workspace indicator uses this mapping to show an application icon instead of the generic default glyph.
-  Match the mapping on the window class.
-  Run `hyprctl clients -j | jq -r '.[].class' | sort -u` to list classes in the running session.
-- Set Hyprland session environment variables in `modules/desktop/session/hyprland/default.nix` with `env = KEY,VALUE`.
-  `home.sessionVariables` do **not** reach the Hyprland session because UWSM does not source `hm-session-vars.sh`.
-  Source cursor values from `config.stylix.cursor`.
-  Set `XCURSOR_*` and `HYPRCURSOR_*` to the same theme for Bibata.
-- Configure the Steam desktop client as an XWayland application.
-  SDL Wayland selectors do not make the visible client native Wayland.
-  Keep fractional scaling sharp with Hyprland's `xwayland.force_zero_scaling` and Steam's `STEAM_FORCE_DESKTOPUI_SCALING`.
-
-### Firefox
-
-- Manage Firefox search engines through `programs.firefox.search` with `force = true`.
-  Hide built-in engines with `<engine>.metaData.hidden = true` because omission does not remove them.
-  Use current engine ids, such as `default = "ddg"` instead of `"DuckDuckGo"`.
-  Decode the built `search.json.mozlz4` with `mozlz4a -d <search.json.mozlz4>` to check the result.
-- Avoid Home Manager Firefox extension settings unless the whole profile can use the legacy extension-storage backend.
-  Any non-empty `profiles.<name>.extensions.settings.<id>.settings` sets `extensions.webextensions.ExtensionStorageIDB.enabled = false` for the whole profile.
-
-### Neovim
-
-- Nixvim's flake input follows the root nixpkgs source, but its Home Manager module does not reuse the host's `pkgs` instance.
-  Keep `programs.nixvim.nixpkgs.useGlobalPackages = true`.
-  That setting makes Nixvim use the shared package set without warning that its source default changed.
-
-### AI Tooling
-
-- Use produced literals for Herdr key names that include shifted punctuation.
-  For example, use `prefix+<` instead of `prefix+shift+comma`.
-- Treat `~/.pi/agent/skills` as generated output from Home Manager.
-  Do not edit skills in that directory.
-  A new file created there stays outside the repo.
-  Shared global skills come from the `skills` flake through `modules/agents/skills.nix`.
-  Update the `skills` flake input, then rebuild.
-- Keep generated `.agents/skills/.gitignore` files from ignoring symlinked skills.
-  Pi skill discovery honors `.gitignore`, `.ignore`, and `.fdignore` inside scanned skill directories.
-  An ignored symlinked skill does not load even when `.agents/skills/<name>/SKILL.md` exists.
-- Write directly to flake-managed Pi extension, prompt, and skill directories only for throwaway development or local experiments.
-  Home Manager activation can overwrite or hide unmanaged files in those directories.
-  Promote finished work into the dotfiles module before treating it as deployed.
-
-## Gotchas
-
-- Guest modules are host-agnostic wiring, while host files own deployment-specific service configuration such as served volumes and host paths.
-  For example, `guests/copyparty.nix` should expose options and translate them into guest mounts/service settings, while `hosts/pikachu/default.nix` chooses `/inbox`, `/media`, and their backing paths.
-  Guest addresses and routes are host-level configuration because a guest module can be used on multiple hosts.
-- The registry collector reads only top-level host `config.registry` declarations.
-  Registry declarations inside guest interiors live under `config.containers.<guest>.config.registry`.
-  The collected registry does not include those guest-interior declarations.
-  Publish guest values from host-side code, or extend the collector to recurse into guests.
-  See http://git.alexion.dev/alexion/dotfiles/issues/65.
-- A NixOS module function argument default such as `registry ? config.registry` does not safely handle an unprovided module argument.
-  The module system still queries `_module.args.registry`.
-  Evaluation fails when that argument is absent.
-  For an optional special-argument fallback, bind module arguments through `@args`.
-  Test `args ? <name>` inside the module body.
-
-- `chaotic-nyx` must **not** follow this flake's `nixpkgs`.
-  Chaotic builds its packages against its own pinned `nixpkgs`.
-  Its overlay defaults to `onTopOf = "flake-nixpkgs"`, the cache-friendly path.
-  That setup lets `nyx-cache.chaotic.cx` serve the CachyOS kernel instead of building it from source.
-  Chaotic packages do not see this flake's `unstable` or `stable` overlays.
-
-- Remote deploy helpers that run target-side `sudo` over SSH need a TTY.
-  Use `ssh -t` unless the target command cannot prompt for sudo credentials.
-
-- This host has no `python` or `python3` command on its ordinary `PATH`.
-  For one-off Python commands, use Nix explicitly, such as `nix shell nixpkgs#python3 -c python3 <script>`.
-- `nixos-generate-config --show-hardware-config` needs root on this machine, even when it only prints.
-  Without root, it fails with `Failed to retrieve subvolume info for /`.
-  The root filesystem uses btrfs.
-- Nix flake evaluation ignores untracked files in this checkout.
-  Stage or commit new auto-loaded modules before evaluating the flake.
-  Otherwise, `nix flake check` and `nixos-rebuild --flake` cannot see those modules.
-  They can then report missing options that exist only in the working tree.
-
-- `sops.secrets.<name>.owner` must name a user known on the decrypting host.
-  Do not set the owner to a guest-only service user unless the host also declares that user.
-  Use a host-visible owner plus a shared group mode when the guest service can read the decrypted secret file through its group.
-
-- Actual Budget's NixOS service runs `actual-server` with `WorkingDirectory = services.actual.settings.dataDir`.
-  The `actual-server` CLI wrapper sets `ACTUAL_CONFIG_PATH=./config.json` when the working directory contains `config.json`.
-  That environment variable overrides the config path generated by the NixOS module.
-  During migration from old community-script state, move or rewrite a copied `/data/config.json`.
-  Otherwise, the copied file shadows the declarative module settings.

CLAUDE.md

@@ -1,5 +1,96 @@
-# Claude Code compatibility
+# dotfiles-nixos
 
-You MUST read and follow [`AGENTS.md`](AGENTS.md) before doing any work in this repository.
-`AGENTS.md` is the canonical project instruction file.
-This file exists only so Claude Code discovers that canonical instruction file.
+One flake that builds every machine the user owns.
+The domain model (Host, Module, Skeleton, Auto-loader, Enable convention, overlays) lives in `.claude/CONTEXT.md`; the current deliverable's spec is `.claude/spec/laptop-mvi.md`.
+
+## Conventions
+
+- Write comments only where they earn their place, and keep them concise.
+  Assume the reader can read code: comment the "why", not the "what", and explain "what" only when it is genuinely non-obvious.
+  A comment must be self-contained to its file — accurate to a reader looking at that file alone.
+  Do not write about history ("used to be X", "now moved here") or future state, about how a value is consumed elsewhere, or to justify the choice against alternatives; state the positive reason a thing exists, keeping any real stakes as a present-tense consequence.
+  The only permitted cross-file mention is a bare pointer explaining why something is *absent* here (e.g. "disko derives `fileSystems`; none declared here"), never narrating what the other file or tool does.
+  Do not use the domain model's capitalized terms (Host, Module, Skeleton, Auto-loader, Enable convention) as glossary references; describe things in plain language, using "host"/"module" only as ordinary lowercase nouns.
+  Never reference agent-facing state (anything under `.claude/` or `CLAUDE.md`).
+  A file-top header is one concise purpose line, added only where the filename or path does not already say it — never a feature inventory of the code below.
+  For a placeholder, say so plainly plus any actionable present-tense directive ("Placeholder: regenerate with nixos-generate-config on the target machine"), never "placeholder for <missing feature>".
+  Option `description`/`mkEnableOption` strings are user-facing documentation rather than comments, so they may describe behaviour more fully — but the self-contained rule and the bans on glossary terms and agent-state references still apply.
+- Start each sentence of a comment on its own line, as with Markdown prose.
+  A sentence needing more than one line is first a prompt to ask whether it should be two sentences.
+  Only when it genuinely cannot be split does it wrap, and then it wraps normally at the right margin.
+  Never break a line early at a comma or clause boundary to make it read as a unit.
+  Never use a semicolon, in a comment or in authored prose.
+  Recast as two sentences instead.
+  Only reformat comments you are actually writing or changing.
+- Comments posted to Gitea (pull requests, issues, reviews) go out under the operator's account, so sign every one to make clear the author is the agent, not the operator.
+  End the comment with a `— Claude` sign-off.
+  (A dedicated bot account may replace this later; until then, the sign-off is the only marker.)
+- Commit messages follow Conventional Commits, specified in `docs/conventional-commits.md`.
+  Scope is the module or host the change belongs to (`fish`, `nvim`, `neogaia`), omitted for repo-wide changes.
+  Keep messages free of Gitea-specific references: this repository is mirrored to GitHub, where issue and pull-request numbers resolve to unrelated things.
+
+## Gotchas
+
+- This repo is developed on `neogaia`, which now runs the NixOS it builds.
+  Flakes and the chaotic substituter come from this flake's own `nix.settings`, so no `NIX_CONFIG` export or per-command `--extra-experimental-features` is needed, and building a toplevel with `boot.kernelPackages = linuxPackages_cachyos` fetches the kernel from `nyx-cache` rather than compiling it.
+  Both were true only while the machine still ran CachyOS against a distro Nix daemon.
+- The substituters a `nix build` fetches from are the **daemon's** (`/etc/nix/nix.conf`), *not* the `nix.settings` of the config being built — those only govern the built system.
+  The two coincide here because the dev host runs this flake; they diverge on any machine that does not.
+- Git identity is declared in the flake by `modules/git.nix`, which writes `alexion <contact@alexion.dev>` — the identity all history uses — on any host enabling `modules.git`.
+  Every new host has to enable it, so that a host reads as a full checklist of what it carries.
+  It is deployed on `neogaia` and verified: a commit in a repository outside this checkout is authored `alexion <contact@alexion.dev>` with no override.
+  Verify it that way rather than from this checkout, whose `.git/config` carries the same identity and would mask a broken module.
+  Home-manager writes `~/.config/git/config`, and `~/.gitconfig` is a second global file that git also reads, outranking it on any key set in both.
+  `~/.gitconfig` currently holds only a `tea` credential helper and no `user.*`, so it does not shadow the identity, but it is undeclared and will not survive a reimage.
+- `git config --global` is a listing and writing filter over `~/.gitconfig` alone, **not** a view of what git resolves.
+  With both global files present it prints only `~/.gitconfig`, which reads as proof that `~/.config/git/config` is being ignored entirely.
+  It is not: drop `--global` and both files appear, each key resolving to the last file that sets it.
+  A `git config --global <key> <value>` write also lands in `~/.gitconfig`, the file that outranks the flake-managed one.
+- The primary build/verify seam for any Host is `nix flake check`, which builds `checks.x86_64-linux.<host>` (the system toplevel); cheap targeted checks use `nix eval .#nixosConfigurations.<host>.config...`.
+- A flake only sees **git-tracked** files, so a new file that has not been `git add`ed is invisible to evaluation even though it exists on disk.
+  The failure names the path and reads as if the file were missing: `error: Path 'secrets/shared.yaml' does not exist in Git repository`.
+  Staging is enough; the file need not be committed.
+- chaotic-nyx must **not** follow our `nixpkgs`, and its packages are built against chaotic's own pinned nixpkgs (its overlay defaults to `onTopOf = "flake-nixpkgs"`, the cache-friendly path).
+  That is what lets the `nyx-cache.chaotic.cx` binary cache hit instead of compiling the CachyOS kernel from source; the tradeoff is that chaotic packages do not see our `unstable`/`stable` overlays.
+- The remote is self-hosted Gitea (`git.alexion.dev`), and the forge CLI is `gitea-axi` rather than `tea`.
+  `gitea-axi` resolves the repository from the `origin` remote and discovers credentials from a `tea` login whose host matches the remote, so both are implicit inside a checkout.
+  It is installed on `neogaia` by `modules.gitea-axi`, and verified: `gitea-axi` run from this checkout renders the `alexion/dotfiles` dashboard authenticated, so the claude-code `SessionStart` hook that runs it now resolves to a real binary rather than a missing one.
+  The package wraps the binary so `git` and `tea` are reachable without being on `PATH`, while still preferring the operator's own where present.
+  Credentials: `~/.config/tea/config.yml` holds a token-bearing login named `alexion`, which `gitea-axi` uses and which also opens pull requests directly with `nix run nixpkgs#tea -- pr create --login alexion --repo alexion/dotfiles --base main --head <branch> ...`.
+  The `--repo` flag is required on that path, since `tea` resolves `origin` only for a login whose SSH host matches.
+  The same token reads PR discussion, which `tea` itself does poorly: `tea pr <n> --comments` prints only the body, and `-f comments` returns no comments field at all.
+  Use the API instead, taking the token from `.logins[] | select(.name=="alexion") | .token`.
+  Review comments are **not** at `/issues/<n>/comments` — that endpoint holds only top-level discussion and is usually empty.
+  Inline comments need two calls: `/pulls/<n>/reviews` for the review ids, then `/pulls/<n>/reviews/<id>/comments` for the bodies, whose `path` and `diff_hunk` fields say what each one is attached to.
+  A review row with an empty `body` is the normal shape when the operator left only inline comments.
+- SSH **host** keys (`ssh_host_<type>_key`, served by the daemon from `/etc/ssh` or a secret) are not user authentication keys (`~/.ssh/id_ed25519`, offered to a remote server).
+  The `ssh_host_` prefix is OpenSSH's own name for the former, and the `root@<host>` trailing field in a `.pub` is a free-text comment stamped by `ssh-keygen` at generation time, not a claim about which account uses the key.
+  On this machine the two are provably distinct: the daemon presents `SHA256:2ysuBX0+Z6GbdCTujz5JHX6rqnJzIyWhYNrxdhhGwEM`, while pushes to `git.alexion.dev` authenticate with `SHA256:nEhHwtHDnLlsuFxyfp+cETgHUZ8xDMxaPVmYM5vuCkA`.
+  Renaming host keys after user keys, or vice versa, is therefore always wrong.
+- `~/.claude/skills` is generated by home-manager with `recursive = true`, so the directories are real and writable but every leaf file is a read-only symlink into the store.
+  Editing a skill in place fails; its source is `modules/claude-code/skills/<name>/` here, applied by a rebuild.
+  Creating a new file under `~/.claude/skills/` succeeds silently and is the trap — it stays outside the repo and reaches no other machine.
+  Copying out of that tree needs `cp -rL` plus `chmod -R u+w`: a plain `cp -r` copies the symlinks, putting store paths into the destination, and dereferenced files keep the store's read-only mode.
+- `home-manager.users.<user>.home.file` is keyed by **absolute** path, not by a path relative to the home directory.
+  Evaluating `home.file.".claude/CLAUDE.md"` fails with "does not provide attribute"; the working key is `home.file."/home/alexion/.claude/CLAUDE.md"`.
+  List the real keys with `nix eval --json .#nixosConfigurations.<host>.config.home-manager.users.<user>.home.file --apply builtins.attrNames` rather than guessing one.
+  A key's `.source` is the input file, whose store path differs from the deployed symlink's target (home-manager copies it to a `hm_`-prefixed path) even though the contents match.
+- nixpkgs `vimPlugins.nord-nvim` is `shaunsingh/nord.nvim` (no `require("nord").setup()`); the config wants `gbprod/nord.nvim`, which is packaged as `vimPlugins.gbprod-nord`.
+- nixpkgs `vimPlugins.nvim-treesitter` tracks the rewritten `main` branch: there is no `require("nvim-treesitter.configs").setup{ensure_installed,highlight,indent}`. Under nixvim, use `plugins.treesitter` with `highlight.enable`/`indent.enable` and `grammarPackages = with config.programs.nixvim.plugins.treesitter.package.builtGrammars; [ ... ]` — the module's own `package.builtGrammars`, **not** `pkgs.vimPlugins.nvim-treesitter.*` (whose query files can mismatch). The module targets the main branch and enables features via neovim-native APIs (`vim.treesitter.start()`, `require'nvim-treesitter'.indentexpr()`).
+- Neovim is configured via **nixvim** (flake input `nixvim`, consumed as `inputs.nixvim.homeModules.nixvim` added to `home-manager.sharedModules`, config under `home-manager.users.<user>.programs.nixvim`). `nixvim.inputs.nixpkgs.follows = "nixpkgs"` is set; nixvim then emits a benign eval warning that its pinned nixpkgs differs from the followed one — builds and runs fine, do not "fix" it by dropping the follows.
+- To reference the nixvim-built package's own attrs (e.g. treesitter `builtGrammars`) inside our NixOS module, give `home-manager.users.<user>` the module-function form (`hm: { programs.nixvim = { ... hm.config.programs.nixvim... }; }`), since the outer `config` is the NixOS config, not the home-manager one.
+- The agent's Bash sandbox blocks `sudo` and swallows it into a bare exit 1 with **no stderr**, which looks identical to the command itself failing.
+  Re-run with the sandbox disabled to see the real error (`sudo: a password is required`) before diagnosing anything else.
+  Separately, `nixos-generate-config --show-hardware-config` needs root on this machine even just to print: unprivileged it dies at `Failed to retrieve subvolume info for /`, because the root filesystem is btrfs.
+- Sudo's credential cache is keyed per user rather than per terminal (`timestamp_type=global`, 60-minute window, declared by the claude-code module), so an authentication made in one terminal counts for commands the agent runs.
+  Warming it with `sudo -v` through the agent's own shell — including the `!` prefix — never works: that shell has no controlling terminal, and sudo reports `a terminal is required to read the password`.
+  It has to be a separate terminal.
+  A `PreToolUse` hook refuses privileged commands while the cache is cold, so a cold cache announces itself instead of stalling; a failure *without* that message is the sandbox, not the cache.
+- An `mkOption` of a list or attribute-set type is **not** mandatory the way a scalar one is.
+  Those types carry an `emptyValue`, so an option declared with no `default` and never set evaluates to `[ ]` or `{ }` instead of failing with "option used but not defined".
+  A declaration that is genuinely required cannot be expressed by omitting the default — it needs an assertion, or a default chosen so that the silent case is the safe one.
+  This bites hardest where the empty value is itself dangerous, such as a list of authorized SSH keys, where it means a machine nobody can reach.
+- `home-manager.users.<user>` cannot be assigned twice at the same level in one module: `home-manager.users.${user}.home.packages` alongside `home-manager.users.${user}.programs.x` fails with `error: dynamic attribute 'alexion' already defined`.
+  The interpolated key makes it a dynamic attribute, which nix will not merge the way it merges static paths.
+  Nest both under a single `home-manager.users.${user} = { ... }`.
+- **Verifying a nixvim change headless:** `programs.nixvim.build.package`'s wrapper has **no `-u`**, so running `$OUT/bin/nvim` loads the caller's `~/.config/nvim` (the dev host's real config), *not* the built config — silently. To exercise the built config, launch with `-u "$(nix build --no-link --print-out-paths .#…programs.nixvim.build.initFile)"` and a scratch `HOME`/`XDG_CONFIG_HOME`. `conceallevel` is window-local: set it with `opt_local`/`vim.wo`, never `vim.bo[buf]` (which errors).

docs/dictionary.md

@@ -1,59 +0,0 @@
-# Technical Writing and Domain Dictionary
-
-This dictionary defines project-specific controlled vocabulary, prohibited terms, and domain allowlists.
-It applies to comments, user-facing descriptions, commit prose, pull-request prose, and Markdown documentation in this repository.
-
-ASD-STE100 Simplified Technical English partly informs these rules.
-This repository uses those ideas as a local style discipline.
-It does not claim formal ASD-STE100 compliance.
-
-## Strictly Banned Fluff and Latin Terms
-
-Do not use these Latin abbreviations, conversational filler words, and subjective qualifiers.
-Remove them or use the approved replacements.
-
-| Disapproved Term | Approved Replacement | Notes |
-| :--- | :--- | :--- |
-| `i.e.` | `that is` | Latin abbreviation. Unclear to non-native speakers. |
-| `e.g.` | `for example` | Latin abbreviation. |
-| `etc.` | `and so forth`, `and others` | Latin abbreviation. Vague and non-exhaustive. |
-| `vs.` / `versus` | `compared to`, `against` | Latin abbreviation. |
-| `via` | `by using`, `through`, `with` | Latin term. Prefer direct prepositions. |
-| `ad hoc` | `one-off`, `for this case` | Latin term. Prefer direct wording. |
-| `simply` | omit | Subjective filler. Code and concepts are not inherently simple. |
-| `just` | omit | Minimizing filler word. |
-| `obviously` | omit | Subjective qualifier. |
-| `clearly` | omit | Subjective qualifier. |
-| `easily` | omit | Subjective qualifier. |
-| `properly` | `correctly`, or specify exact behavior | Vague and subjective. State the exact condition. |
-| `as necessary` | specify exact condition | Ambiguous. Define the condition explicitly. |
-| `very` / `quite` | omit | Empty intensifiers. |
-| `basically` | omit | Conversational filler. |
-| `actually` | omit | Conversational filler. |
-| `really` | omit | Empty intensifier. |
-| `furthermore` / `moreover` | `also`, `and` | Overly formal transitional filler. |
-
-## Technical and Domain Allowed Language
-
-Use only approved project-specific terms as controlled vocabulary in documentation and comments.
-Add a term here when repeated project prose needs it.
-Use the simplest accurate word when a term is not listed.
-
-| Approved Domain Term | Category | Description and Permitted Context |
-| :--- | :--- | :--- |
-| agent | Agent tooling | An AI coding assistant acting in the operator's environment. |
-| operator | Agent tooling | The human driving the development process. Use when distinguishing the human from the agent acting on their behalf. |
-| guest | dotfiles | A systemd-nspawn container managed by this flake. Use for configured containers under `guests/`. |
-| host | dotfiles | A machine with a NixOS configuration built by this flake. |
-| module | dotfiles | In this repository, a self-contained configuration under `modules/`. Use for one program, service, or subsystem. |
-| registry | dotfiles | A typed configuration namespace whose entries can be collected across hosts and reused by other configuration. |
-| Conventional Commits | Git | A commit-message format defined in `docs/conventional-commits.md`. |
-| forge | Git | A web service that hosts Git repositories, pull requests, issues, and code review comments. Use when the exact provider does not matter. |
-| flake | Nix | A Nix project with pinned inputs and declared outputs. Use for the repository-level build unit defined by `flake.nix`. |
-| assembly file | Nix | A Nix file under `flake/` that constructs flake outputs or arguments passed to NixOS modules. |
-| assembly function | Nix | A project function in `flake/` that creates modules, systems, or output values. |
-| library file | Nix | A Nix file that defines reusable project functions instead of a NixOS module or flake output. |
-| library function | Nix | A pure project function exposed under `util`. |
-| NixOS module | Nix | A Nix file evaluated by `nixosSystem` for a NixOS configuration. |
-| overlay | Nix | A function that modifies a Nix package set by adding or replacing packages. |
-| workspace | Window management | A named or numbered group of windows in a graphical session. Some desktop environments call this a virtual desktop. |

docs/install.md

@@ -103,8 +103,7 @@ $ cd dotfiles
 Do **not** point `disko-install` straight at the Gitea flake URL.
 Gitea serves HTTPS with a self-signed certificate and expects authentication, and Nix's flake fetcher has no easy way to skip certificate verification or supply those credentials mid-install.
 A plain `git clone` sidesteps that entirely — over SSH there is no TLS, and over HTTPS git takes the `sslVerify=false` above that the flake fetcher won't — and then `disko-install` consumes the flake from a local path, where no fetch of our repo happens during the build.
-(Every other flake input is public and still fetched from GitHub over ordinary, valid TLS.
-Only our own repo is the problem the local clone solves.)
+(Every other flake input is public and still fetched from GitHub over ordinary, valid TLS; only our own repo is the problem the local clone solves.)
 
 ### 3. Generate the host identity
 
@@ -171,7 +170,7 @@ Then populate that file, which needs no existing identity because encrypting onl
 $ nix run nixpkgs#sops -- secrets/newhost.yaml
 ```
 
-A host with `modules.network.ssh.enable` expects one entry per key type, named `ssh-host-<type>-key`, each holding a private key generated with `ssh-keygen -t <type> -N "" -f /tmp/<type>`.
+A host with `modules.ssh.enable` expects one entry per key type, named `ssh-host-<type>-key`, each holding a private key generated with `ssh-keygen -t <type> -N "" -f /tmp/<type>`.
 The build fails at evaluation if a declared secret is absent from the file, so a host that enables the daemon without these will not install.
 Commit the matching public halves beside the host's configuration in plaintext, since publishing them is their purpose.
 
@@ -202,20 +201,17 @@ $ sudo nix --extra-experimental-features 'nix-command flakes' run \
 What each part does:
 
 - `--flake .#neogaia` installs the `neogaia` `Host` from the local clone.
-- `--disk main /dev/nvme0n1` maps disko's `main` disk to the NVMe device.
-  It matches the device declared in `hosts/neogaia/disk.nix` and is stated explicitly so there is no doubt about the target.
+- `--disk main /dev/nvme0n1` maps disko's `main` disk to the NVMe device; it matches the device declared in `hosts/neogaia/disk.nix` and is stated explicitly so there is no doubt about the target.
 - `--write-efi-boot-entries` writes the systemd-boot entry into this machine's NVRAM, because the disk stays in the machine it was installed from.
 - The two `--option` lines are the important part: they hand the **chaotic binary cache** to the install-time Nix daemon on the live ISO.
 
 The chaotic substituter must be passed here explicitly.
-The `nix.settings` in the flake configure the substituters of the *installed* system, not the live ISO's daemon that runs this build.
-The ISO's daemon has no `substituters` beyond `cache.nixos.org`.
+The `nix.settings` in the flake configure the substituters of the *installed* system, not the live ISO's daemon that runs this build; the ISO's daemon has no `substituters` beyond `cache.nixos.org`.
 Without these two `--option` flags, the build cannot fetch the prebuilt CachyOS kernel and **compiles `linuxPackages_cachyos` (and its toolchain) from source on the USB stick** — a very long detour that the cache avoids.
 Because the install runs as root, and root is a trusted Nix user, the daemon honours these client-supplied substituter settings.
 
 Partway through, disko formats the LUKS container and **prompts for a disk-encryption passphrase**.
-This is the passphrase you will type at every boot to unlock the disk.
-Choose it deliberately.
+This is the passphrase you will type at every boot to unlock the disk; choose it deliberately.
 
 When it finishes it prints `disko-install succeeded`.
 `disko-install` unmounts the target filesystem on exit, so nothing is mounted at this point — step 6 remounts it.

docs/nix.md

@@ -1,270 +0,0 @@
-# Nix Conventions
-
-This document records local Nix style and design conventions.
-Use these conventions when changing this flake.
-Read this document with `docs/dictionary.md`.
-
-## Names
-
-### Reserve `lib` for `nixpkgs.lib`
-
-Use `lib` only for the base `nixpkgs.lib` value.
-Do not use `lib` for project functions.
-Use `util` for library functions passed through module arguments.
-Use `flake.mk<Name>` for assembly functions used by flake outputs.
-
-Avoid:
-
-```nix
-specialArgs = {
-  lib = util;
-};
-```
-
-Use:
-
-```nix
-specialArgs = {
-  inherit util;
-};
-```
-
-Then call library functions through `util` inside modules:
-
-```nix
-{
-  lib,
-  util,
-  ...
-}:
-{
-  networking.networkmanager.unmanaged = [ "interface-name:${util.bridgeName 10}" ];
-}
-```
-
-### Name project function namespaces by role
-
-Put pure project functions under `util`.
-Put functions that create systems or output values under `flake`.
-This keeps data-only functions separate from functions that carry flake context.
-
-Avoid:
-
-```nix
-util.mkHosts { root = self + "/hosts"; }
-```
-
-Use:
-
-```nix
-flake.mkHosts { root = self + "/hosts"; }
-```
-
-## File Placement
-
-### Put files in the directory that owns their role
-
-Choose the file location before writing a Nix file.
-Put assembly files under `flake/`.
-Put library files under `lib/`.
-Put modules under `modules/`.
-Put host configurations under `hosts/<name>/`.
-Put host-side guest wiring under `guests/`.
-Put registry definitions under `registry/`.
-Keep `flake.nix` focused on inputs and output wiring.
-Do not add root-level Nix files other than `flake.nix`.
-
-A module is self-contained configuration under `modules/`.
-A module configures one program, service, or subsystem.
-Files under `hosts/`, `guests/`, and `modules/` return NixOS modules.
-
-### Use `default.nix` for module directories with support files
-
-Use `default.nix` as the primary module when a module directory owns support files.
-Keep sibling files for data or code read by that primary module.
-
-Avoid:
-
-```text
-modules/shell/fish/fish.nix
-modules/shell/fish/config.fish
-```
-
-Use:
-
-```text
-modules/shell/fish/default.nix
-modules/shell/fish/config.fish
-```
-
-### Use non-module `default.nix` files only for directory assembly
-
-Outside `modules/`, use `default.nix` to connect files in its directory.
-Do not define primary assembly functions in `default.nix`.
-Put primary assembly functions in named files.
-
-Avoid:
-
-```text
-flake/default.nix  # defines mkHost
-```
-
-Use:
-
-```text
-flake/default.nix  # imports ./host.nix
-flake/host.nix     # defines mkHosts
-```
-
-### Keep assembly files focused on one concept
-
-Give each assembly file under `flake/` one top-level concept.
-Keep helper functions private to that file when no other file needs them.
-Export the constructor for the concept when another assembly file needs it.
-Name that constructor `mk<Concept>`.
-
-Avoid:
-
-```nix
-{
-  inherit collectNixFiles mkHost mkHosts;
-}
-```
-
-Use:
-
-```nix
-{
-  inherit mkHosts;
-}
-```
-
-## Function Arguments
-
-### Use closed interfaces for assembly files and library files
-
-Use exact function argument patterns for assembly files and library files.
-The caller owns the argument set for these files.
-The imported file names each accepted attribute.
-The imported file rejects stale or accidental extra attributes.
-
-Avoid:
-
-```nix
-{
-  inputs,
-  lib,
-  self,
-  ...
-}:
-```
-
-Use:
-
-```nix
-{
-  inputs,
-  lib,
-  self,
-}:
-```
-
-### Pass function arguments explicitly
-
-Pass only the values an assembly file or library file needs.
-Bind `lib` to the base `nixpkgs.lib` value at the call site.
-Use `inherit` only for values that keep the same name.
-
-Avoid:
-
-```nix
-import ./flake inputs
-```
-
-Use:
-
-```nix
-let
-  inherit (nixpkgs) lib;
-in
-import ./flake { inherit lib inputs self; }
-```
-
-### Keep NixOS module interfaces open
-
-Files under `hosts/`, `guests/`, and `modules/` return NixOS modules.
-`nixosSystem` owns their argument shape.
-Name each argument the module uses.
-Keep `...` so the module accepts standard arguments and special arguments.
-
-Avoid:
-
-```nix
-{
-  config,
-  lib,
-  pkgs,
-  registry,
-}:
-```
-
-Use:
-
-```nix
-{
-  config,
-  lib,
-  pkgs,
-  registry,
-  ...
-}:
-```
-
-## `let` Bindings
-
-### Use role-specific binding names
-
-A `let` binding name must explain the value's role in the expression.
-Avoid names that describe only the value's type.
-
-Avoid:
-
-```nix
-let
-  names = lib.attrNames hosts;
-in
-lib.genAttrs names mkHost
-```
-
-Use:
-
-```nix
-let
-  hostNames = lib.attrNames hosts;
-in
-lib.genAttrs hostNames mkHost
-```
-
-## Standard Library Calls
-
-### Qualify standard library calls in flake assembly
-
-Use qualified standard library calls inside assembly files.
-Use `lib.mapAttrs` instead of inheriting `mapAttrs` from `lib`.
-This keeps the source of each function visible.
-
-Avoid:
-
-```nix
-let
-  inherit (lib) mapAttrs;
-in
-mapAttrs f attrs
-```
-
-Use:
-
-```nix
-lib.mapAttrs f attrs
-```
-

docs/technical-writing.md

@@ -1,109 +0,0 @@
-# Technical Writing
-
-This guide defines writing rules for comments, user-facing descriptions, commit prose, pull-request prose, and Markdown documentation.
-These rules apply throughout this repository.
-
-ASD-STE100 Simplified Technical English partly informs these rules.
-This repository uses those ideas as a local style discipline.
-It does not claim formal ASD-STE100 compliance.
-
-Read the local dictionary with this guide.
-In this guide, “the dictionary” means `docs/dictionary.md`.
-The dictionary defines banned terms and the strict domain allowlist.
-
-## Structural Conciseness and Grammar Rules
-
-- **Clear and concise style:** Use direct, concise writing.
-  Use simple present tense for factual descriptions.
-  Do not use uncertainty words such as `could`, `might`, and `should` unless uncertainty is the subject.
-  Use each domain word with the meaning assigned in the dictionary.
-  Avoid: `The tool should usually handle the input correctly.`
-  Use: `The tool validates the input.`
-- **Avoid jargon and inflated language:** Use common technical words.
-  Avoid unnecessary jargon in three categories:
-  1. Linguistic and grammatical meta-jargon.
-     Avoid: `modal auxiliaries`
-     Use: `uncertain words`
-  2. Inflated corporate phrasing.
-     Avoid: `utilize`
-     Use: `use`
-     Avoid: `commence`
-     Use: `start`
-  3. Unapproved domain inventions.
-     Do not use project-specific terms unless the dictionary defines them.
-     General technical words do not need dictionary entries.
-     Add a common word to the dictionary when it has a project-specific meaning.
-     If a term is vague or overloaded, choose one precise term.
-     List avoided alternatives in the dictionary.
-  Choose the simplest word that accurately communicates the meaning.
-- **Sentence length limits:** Code comments, user-facing descriptions, and procedural instructions have a 20-word limit.
-  Descriptive Markdown paragraphs have a 25-word limit.
-  Do not put multiple sentences on one physical line.
-  Wrap a sentence across multiple physical lines when readability requires it.
-  Split long sentences into multiple concise sentences.
-  Avoid: `The command configures the service with the generated settings and restarts it after the file changes.`
-  Use: `The command configures the service with the generated settings.`
-  Use: `It restarts the service after the file changes.`
-- **Active voice:** Always use active voice.
-  The subject must perform the action.
-  Do not use passive voice.
-  Avoid: `Stale entries are invalidated by the cache.`
-  Use: `The cache invalidates stale entries.`
-- **Imperative mood:** Procedural instructions and task steps must start with an imperative verb.
-  Summary fragments for declarations use third-person singular.
-  Avoid: `The token should be validated before use.`
-  Use for a task step: `Validate the token before use.`
-  Use for a declaration summary: `Validates the token before use.`
-- **Noun clusters:** Do not write more than three consecutive nouns without a preposition or hyphen.
-  Avoid: `session cache entry lookup`
-  Use: `lookup of session cache entries`
-- **One idea per sentence:** Express only one instruction or core concept per sentence.
-  Do not combine multiple operations in one compound sentence.
-  Avoid: `Validate the input and restart the service when validation succeeds.`
-  Use: `Validate the input.`
-  Use: `Restart the service when validation succeeds.`
-- **Code token exemption:** Text in Markdown backticks, URLs, and code blocks counts as one word.
-  Sentence-length limits and noun-cluster limits do not apply to these tokens.
-  Example: `curl --fail --silent https://example.com/health` counts as one word.
-- **Cause and time precision:** Use `because` for causality.
-  Use `since` only for passage of time.
-  Use `as` only for simultaneous action.
-  Avoid: `Since the token is expired, validation fails.`
-  Use: `Because the token is expired, validation fails.`
-
-## In-Code Documentation Conventions
-
-- **Declaration coverage and exemptions:** Document public interfaces, configuration options, fields, and non-trivial public methods.
-  Omit comments on obvious declarations when the name and context are self-explanatory.
-  Avoid: `Enable this option.`
-  Use: `Enables automatic cleanup after a successful run.`
-- **Declaration non-redundancy:** Comments must explain purpose, preconditions, invariants, or non-obvious consequences.
-  Do not repeat information that the name, type, path, or parameter list already conveys.
-  Avoid: `The timeout option sets the timeout.`
-  Use: `Controls how long the command waits before it reports failure.`
-- **Multi-line declaration comments:** Start multi-line declaration comments with one summary sentence.
-  Put a blank line between the summary and detail paragraphs.
-  Use detail paragraphs for preconditions, invariants, examples, and non-obvious consequences.
-  Avoid:
-
-  ```text
-  The caller must load the signing key before calling this method.
-  Validates the token and returns false for expired tokens.
-  ```
-
-  Use:
-
-  ```text
-  Validates the token.
-
-  The caller must load the signing key before calling this method.
-  Expired tokens return false instead of an error.
-  ```
-- **Code symbol references:** Enclose identifiers, paths, commands, option names, and file names in Markdown backticks.
-  Avoid: Run npm test before editing package.json.
-  Use: Run `npm test` before editing `package.json`.
-- **Boolean descriptions:** Start boolean descriptions with the behavior verb.
-  Use `True if` only when the value reports state instead of enabling behavior.
-  Avoid: `Flag that specifies whether retries are enabled.`
-  Use: `Enables retry behavior.`
-  Use for state: `True if the token is expired.`

flake.lock

@@ -1,73 +1,5 @@
 {
   "nodes": {
-    "base16": {
-      "inputs": {
-        "fromYaml": "fromYaml"
-      },
-      "locked": {
-        "lastModified": 1755819240,
-        "narHash": "sha256-qcMhnL7aGAuFuutH4rq9fvAhCpJWVHLcHVZLtPctPlo=",
-        "owner": "SenchoPens",
-        "repo": "base16.nix",
-        "rev": "75ed5e5e3fce37df22e49125181fa37899c3ccd6",
-        "type": "github"
-      },
-      "original": {
-        "owner": "SenchoPens",
-        "repo": "base16.nix",
-        "type": "github"
-      }
-    },
-    "base16-fish": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1765809053,
-        "narHash": "sha256-XCUQLoLfBJ8saWms2HCIj4NEN+xNsWBlU1NrEPcQG4s=",
-        "owner": "tomyun",
-        "repo": "base16-fish",
-        "rev": "86cbea4dca62e08fb7fd83a70e96472f92574782",
-        "type": "github"
-      },
-      "original": {
-        "owner": "tomyun",
-        "repo": "base16-fish",
-        "rev": "86cbea4dca62e08fb7fd83a70e96472f92574782",
-        "type": "github"
-      }
-    },
-    "base16-helix": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1776754714,
-        "narHash": "sha256-E3OAK27smtATTmX45uoTSRsVD+Y+ZiVVfgM/tjpbtYg=",
-        "owner": "tinted-theming",
-        "repo": "base16-helix",
-        "rev": "4d508123037e7851ad36ebf7d9c48b0e9e1eb581",
-        "type": "github"
-      },
-      "original": {
-        "owner": "tinted-theming",
-        "repo": "base16-helix",
-        "type": "github"
-      }
-    },
-    "base16-vim": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1732806396,
-        "narHash": "sha256-e0bpPySdJf0F68Ndanwm+KWHgQiZ0s7liLhvJSWDNsA=",
-        "owner": "tinted-theming",
-        "repo": "base16-vim",
-        "rev": "577fe8125d74ff456cf942c733a85d769afe58b7",
-        "type": "github"
-      },
-      "original": {
-        "owner": "tinted-theming",
-        "repo": "base16-vim",
-        "rev": "577fe8125d74ff456cf942c733a85d769afe58b7",
-        "type": "github"
-      }
-    },
     "chaotic": {
       "inputs": {
         "flake-schemas": "flake-schemas",
@@ -75,11 +7,11 @@
         "nixpkgs": "nixpkgs"
       },
       "locked": {
-        "lastModified": 1785327209,
-        "narHash": "sha256-heXGjUBU1UsTHFzedDzYct9Cblr6FGzQcYyjCykywh8=",
+        "lastModified": 1784318604,
+        "narHash": "sha256-P/N5ZbGWITiTfmiWpE/1uyXdOCagpgw/YAZLZJSzx/I=",
         "owner": "chaotic-cx",
         "repo": "nyx",
-        "rev": "90cfa9864fa08c923dddeca965103ad44663dd64",
+        "rev": "21a8ef816f34558a438d778057a8809322ea2415",
         "type": "github"
       },
       "original": {
@@ -109,44 +41,6 @@
         "type": "github"
       }
     },
-    "firefox-addons": {
-      "inputs": {
-        "nixpkgs": [
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "dir": "pkgs/firefox-addons",
-        "lastModified": 1785384175,
-        "narHash": "sha256-sWSJPXpQwKJstL4rdhpAQYCYlHK5wOkEHR8/lNHBVb4=",
-        "owner": "rycee",
-        "repo": "nur-expressions",
-        "rev": "db607f3d0afe811bcb3b16266f28b2fc5af4e74f",
-        "type": "gitlab"
-      },
-      "original": {
-        "dir": "pkgs/firefox-addons",
-        "owner": "rycee",
-        "repo": "nur-expressions",
-        "type": "gitlab"
-      }
-    },
-    "firefox-gnome-theme": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1782007937,
-        "narHash": "sha256-PbnJr+eB+9Czol3ReI83dUgEhcn0sDK6TSy6ODTQm88=",
-        "owner": "rafaelmardojai",
-        "repo": "firefox-gnome-theme",
-        "rev": "981bd332015397fb1ca033fa982bd61635160c78",
-        "type": "github"
-      },
-      "original": {
-        "owner": "rafaelmardojai",
-        "repo": "firefox-gnome-theme",
-        "type": "github"
-      }
-    },
     "flake-parts": {
       "inputs": {
         "nixpkgs-lib": [
@@ -168,27 +62,6 @@
         "type": "github"
       }
     },
-    "flake-parts_2": {
-      "inputs": {
-        "nixpkgs-lib": [
-          "stylix",
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1782949081,
-        "narHash": "sha256-vp6Y/Grm98ESt6ceOkWiHWyZRDV3J1RID4w+6NWK9yA=",
-        "owner": "hercules-ci",
-        "repo": "flake-parts",
-        "rev": "17c9d6cdfc60c64f4ee8d306f9bc0b4ccb51481e",
-        "type": "github"
-      },
-      "original": {
-        "owner": "hercules-ci",
-        "repo": "flake-parts",
-        "type": "github"
-      }
-    },
     "flake-schemas": {
       "locked": {
         "lastModified": 1780327564,
@@ -203,40 +76,6 @@
         "url": "https://flakehub.com/f/DeterminateSystems/flake-schemas/%3D0.5.0.tar.gz"
       }
     },
-    "flake-utils": {
-      "inputs": {
-        "systems": "systems_2"
-      },
-      "locked": {
-        "lastModified": 1731533236,
-        "narHash": "sha256-l0KFg5HjrsfsO/JpG+r7fRrqm12kzFHyUHqHCVpMMbI=",
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "rev": "11707dc2f618dd54ca8739b309ec4fc024de578b",
-        "type": "github"
-      },
-      "original": {
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "type": "github"
-      }
-    },
-    "fromYaml": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1731966426,
-        "narHash": "sha256-lq95WydhbUTWig/JpqiB7oViTcHFP8Lv41IGtayokA8=",
-        "owner": "SenchoPens",
-        "repo": "fromYaml",
-        "rev": "106af9e2f715e2d828df706c386a685698f3223b",
-        "type": "github"
-      },
-      "original": {
-        "owner": "SenchoPens",
-        "repo": "fromYaml",
-        "type": "github"
-      }
-    },
     "gitea-axi": {
       "inputs": {
         "home-manager": "home-manager_2",
@@ -245,11 +84,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1785340481,
-        "narHash": "sha256-GSxdQ7w8yYfZnfkXUuZ2fYIKibe9ZU8xDGyqpeTb2tE=",
+        "lastModified": 1784592615,
+        "narHash": "sha256-AH96vm0yYyS9sk35GnagZoWww8s8NHWYuyZJpSStlMM=",
         "ref": "refs/heads/main",
-        "rev": "627fc9a32bb80d97923540fc0d3e9661961462ba",
-        "revCount": 83,
+        "rev": "1468003f5b63f49fcd3cd456c25a8ad4f25716cc",
+        "revCount": 82,
         "type": "git",
         "url": "https://git.alexion.dev/alexion/gitea-axi"
       },
@@ -258,47 +97,6 @@
         "url": "https://git.alexion.dev/alexion/gitea-axi"
       }
     },
-    "gitea-axi_2": {
-      "inputs": {
-        "home-manager": "home-manager_4",
-        "nixpkgs": [
-          "skills",
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1785340481,
-        "narHash": "sha256-GSxdQ7w8yYfZnfkXUuZ2fYIKibe9ZU8xDGyqpeTb2tE=",
-        "ref": "refs/heads/main",
-        "rev": "627fc9a32bb80d97923540fc0d3e9661961462ba",
-        "revCount": 83,
-        "type": "git",
-        "url": "https://git.alexion.dev/alexion/gitea-axi"
-      },
-      "original": {
-        "type": "git",
-        "url": "https://git.alexion.dev/alexion/gitea-axi"
-      }
-    },
-    "gnome-shell": {
-      "flake": false,
-      "locked": {
-        "host": "gitlab.gnome.org",
-        "lastModified": 1776175984,
-        "narHash": "sha256-RJFlFW8GiMei6oqUGrMkGEvVqOH8U7Q8abc1yK4VKD8=",
-        "owner": "GNOME",
-        "repo": "gnome-shell",
-        "rev": "e0fdc4c13250e9a9b8ea9594c83925274f4a5dca",
-        "type": "gitlab"
-      },
-      "original": {
-        "host": "gitlab.gnome.org",
-        "owner": "GNOME",
-        "ref": "50.1",
-        "repo": "gnome-shell",
-        "type": "gitlab"
-      }
-    },
     "home-manager": {
       "inputs": {
         "nixpkgs": [
@@ -307,11 +105,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1785288465,
-        "narHash": "sha256-nCkxaGRtyNheNTxoc527gjOG0BN2zovsWDQVBeKDMW8=",
+        "lastModified": 1784129366,
+        "narHash": "sha256-N5JiyICSeQF14x+OQebNyPpYowOT9Rs1iKyeCylSzOA=",
         "owner": "nix-community",
         "repo": "home-manager",
-        "rev": "36662afed2fa1c9b69bdd03edb92ad572202ca20",
+        "rev": "165228b0efefc3e635e5174020c40ea64271dc25",
         "type": "github"
       },
       "original": {
@@ -348,11 +146,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1785306346,
-        "narHash": "sha256-DScBkW0fOgpGPK2trNoX3ryLTlaC14+gglFo/BhGJ4g=",
+        "lastModified": 1784351324,
+        "narHash": "sha256-By+kuRJZRqs2TuXgtR8vJ8cTKWXw33YG/Yollu5cO1U=",
         "owner": "nix-community",
         "repo": "home-manager",
-        "rev": "e705714e918c3b11affcdd15db2cbe3a070420a0",
+        "rev": "460108009ca1ff69ca2ff19079ca2c838d6e3080",
         "type": "github"
       },
       "original": {
@@ -361,64 +159,6 @@
         "type": "github"
       }
     },
-    "home-manager_4": {
-      "inputs": {
-        "nixpkgs": [
-          "skills",
-          "gitea-axi",
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1784588016,
-        "narHash": "sha256-ouZe80aWEhMLVMkqICFDN+JUw+0FJtCr/bh+hHtRtMg=",
-        "owner": "nix-community",
-        "repo": "home-manager",
-        "rev": "deeb6b7eb7e0c44ae1819c051ce175bd92a85100",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nix-community",
-        "repo": "home-manager",
-        "type": "github"
-      }
-    },
-    "home-manager_5": {
-      "inputs": {
-        "nixpkgs": [
-          "skills",
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1784725727,
-        "narHash": "sha256-J5+C9wsO0lhDyUalQzfplDbRjyHDYeEH5+9sdyXtwa8=",
-        "owner": "nix-community",
-        "repo": "home-manager",
-        "rev": "041a999e8c1c5b731913855909e68d30ca69b8e0",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nix-community",
-        "repo": "home-manager",
-        "type": "github"
-      }
-    },
-    "monorepo": {
-      "inputs": {
-        "nixpkgs": "nixpkgs_2"
-      },
-      "locked": {
-        "lastModified": 1788059616,
-        "narHash": "sha256-HBYT3h0vXRsvmgPOhUW3kgPTkgdl73PEwRTJQ5X48aM=",
-        "path": "/home/alexion/dev",
-        "type": "path"
-      },
-      "original": {
-        "path": "/home/alexion/dev",
-        "type": "path"
-      }
-    },
     "nixos-hardware": {
       "inputs": {
         "nixpkgs": [
@@ -426,11 +166,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1785232496,
-        "narHash": "sha256-65EQYIRRpTdpH8lUiB6Mvo5uBkG60aBIzAJuALfx+O0=",
+        "lastModified": 1784310968,
+        "narHash": "sha256-rkSPTePrKqs4dg+i7ZFCq93+HrClac6oSwXX927SVjA=",
         "owner": "NixOS",
         "repo": "nixos-hardware",
-        "rev": "2e790b0a6be8ec2b76174ac0931b8ff11919ec98",
+        "rev": "779c32a00155994c86cde8213a8dd4df139d4355",
         "type": "github"
       },
       "original": {
@@ -441,11 +181,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1785090369,
-        "narHash": "sha256-m0pDuRJG7EDo9ri+4Ksu83VsI+PlxNC9lNBfydejce4=",
+        "lastModified": 1784120854,
+        "narHash": "sha256-KesHgItiZPgGX740axSiQLcIQ8D24MDqNpkKYWIek8k=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "624af665418d3c65d544145b4d34ad696439570e",
+        "rev": "753cc8a3a87467296ddd1fa93f0cc3e81120ee46",
         "type": "github"
       },
       "original": {
@@ -457,11 +197,11 @@
     },
     "nixpkgs-stable": {
       "locked": {
-        "lastModified": 1785133411,
-        "narHash": "sha256-Yjv0WEg39KRYS0rBdTbu6Fc/or/ihAKk13W9sQ6VWd0=",
+        "lastModified": 1784280462,
+        "narHash": "sha256-DtoqIqM7VkR6NxAkcLpMwmi02USwWb3JdmNGLyhthc0=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "2f5a153c270b70cb0f8c11f46d96d6d3bc39f4e3",
+        "rev": "293d6abedf0478e681a4dfcfcb35b30fc796a32f",
         "type": "github"
       },
       "original": {
@@ -473,11 +213,11 @@
     },
     "nixpkgs-unstable": {
       "locked": {
-        "lastModified": 1785301185,
-        "narHash": "sha256-eoS3KQTO0aPWXZvIaRbRAzSSHW3l5wdMFXtT1ISfoKA=",
+        "lastModified": 1784347607,
+        "narHash": "sha256-VI5cdo27nEZ3m1SlgB8RvBbrqFUO2/dUgrrLWe407oA=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "9bc02893134c733dd85de46ee4fb2fac696b5529",
+        "rev": "31cd72fdba8fa052e437ce7e6879c4fe62def10f",
         "type": "github"
       },
       "original": {
@@ -489,11 +229,11 @@
     },
     "nixpkgs_2": {
       "locked": {
-        "lastModified": 1785318670,
-        "narHash": "sha256-dN6Ou5x/+23FZLEpYP3IffO+NyJFzUlGumt1uu3MMaY=",
+        "lastModified": 1784120854,
+        "narHash": "sha256-KesHgItiZPgGX740axSiQLcIQ8D24MDqNpkKYWIek8k=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "0954f7ee2f6bb3dc7d4e3d0d8bcb8fd4bde4cfc5",
+        "rev": "753cc8a3a87467296ddd1fa93f0cc3e81120ee46",
         "type": "github"
       },
       "original": {
@@ -512,11 +252,11 @@
         "systems": "systems"
       },
       "locked": {
-        "lastModified": 1785364321,
-        "narHash": "sha256-BLuHl+nZKb+FDq3GAM6L+UBEiyVepXANA31fT1F56pw=",
+        "lastModified": 1784057377,
+        "narHash": "sha256-yycNej5//EsRbV10moBoh+/63vXEwZD1ZFEiRm6C9rQ=",
         "owner": "nix-community",
         "repo": "nixvim",
-        "rev": "acd69cc15d57004e8cb4495034320263a3d362ea",
+        "rev": "07180a087e4a00720dc0731cbcd8dec796974381",
         "type": "github"
       },
       "original": {
@@ -525,73 +265,18 @@
         "type": "github"
       }
     },
-    "nur": {
-      "inputs": {
-        "flake-parts": [
-          "stylix",
-          "flake-parts"
-        ],
-        "nixpkgs": [
-          "stylix",
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1783439237,
-        "narHash": "sha256-WUr8JF2v3n4Y30E5dxv4sAgNJXpVDBoCQNoQ/V4+n4o=",
-        "owner": "nix-community",
-        "repo": "NUR",
-        "rev": "b70bb66c7bcd162642f3a609bc16843c7059f503",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nix-community",
-        "repo": "NUR",
-        "type": "github"
-      }
-    },
     "root": {
       "inputs": {
         "chaotic": "chaotic",
         "disko": "disko",
-        "firefox-addons": "firefox-addons",
         "gitea-axi": "gitea-axi",
         "home-manager": "home-manager_3",
-        "monorepo": "monorepo",
         "nixos-hardware": "nixos-hardware",
-        "nixpkgs": [
-          "monorepo",
-          "nixpkgs"
-        ],
+        "nixpkgs": "nixpkgs_2",
         "nixpkgs-stable": "nixpkgs-stable",
         "nixpkgs-unstable": "nixpkgs-unstable",
         "nixvim": "nixvim",
-        "skills": "skills",
-        "sops-nix": "sops-nix",
-        "stylix": "stylix"
-      }
-    },
-    "skills": {
-      "inputs": {
-        "flake-utils": "flake-utils",
-        "gitea-axi": "gitea-axi_2",
-        "home-manager": "home-manager_5",
-        "nixpkgs": [
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1787455371,
-        "narHash": "sha256-MJ0bX4/cksSbGl7v9o0l+Wy1xAEa3BgzG7Hs8EEGde0=",
-        "ref": "refs/heads/main",
-        "rev": "9a1d21da4d3e70165ff772967d639df244dcc2ea",
-        "revCount": 55,
-        "type": "git",
-        "url": "https://git.alexion.dev/alexion/skills"
-      },
-      "original": {
-        "type": "git",
-        "url": "https://git.alexion.dev/alexion/skills"
+        "sops-nix": "sops-nix"
       }
     },
     "sops-nix": {
@@ -614,39 +299,6 @@
         "type": "github"
       }
     },
-    "stylix": {
-      "inputs": {
-        "base16": "base16",
-        "base16-fish": "base16-fish",
-        "base16-helix": "base16-helix",
-        "base16-vim": "base16-vim",
-        "firefox-gnome-theme": "firefox-gnome-theme",
-        "flake-parts": "flake-parts_2",
-        "gnome-shell": "gnome-shell",
-        "nixpkgs": [
-          "nixpkgs"
-        ],
-        "nur": "nur",
-        "systems": "systems_3",
-        "tinted-kitty": "tinted-kitty",
-        "tinted-schemes": "tinted-schemes",
-        "tinted-tmux": "tinted-tmux",
-        "tinted-zed": "tinted-zed"
-      },
-      "locked": {
-        "lastModified": 1784676123,
-        "narHash": "sha256-ndyanKzw90yX2nUVFmTuYqXidUNymtMfgmIHyNdhht0=",
-        "owner": "danth",
-        "repo": "stylix",
-        "rev": "66714e5ce44269ecc58c20d9196da8dbe1b27a31",
-        "type": "github"
-      },
-      "original": {
-        "owner": "danth",
-        "repo": "stylix",
-        "type": "github"
-      }
-    },
     "systems": {
       "locked": {
         "lastModified": 1774449309,
@@ -662,100 +314,6 @@
         "repo": "default",
         "type": "github"
       }
-    },
-    "systems_2": {
-      "locked": {
-        "lastModified": 1681028828,
-        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
-        "owner": "nix-systems",
-        "repo": "default",
-        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nix-systems",
-        "repo": "default",
-        "type": "github"
-      }
-    },
-    "systems_3": {
-      "locked": {
-        "lastModified": 1681028828,
-        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
-        "owner": "nix-systems",
-        "repo": "default",
-        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nix-systems",
-        "repo": "default",
-        "type": "github"
-      }
-    },
-    "tinted-kitty": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1735730497,
-        "narHash": "sha256-4KtB+FiUzIeK/4aHCKce3V9HwRvYaxX+F1edUrfgzb8=",
-        "owner": "tinted-theming",
-        "repo": "tinted-kitty",
-        "rev": "de6f888497f2c6b2279361bfc790f164bfd0f3fa",
-        "type": "github"
-      },
-      "original": {
-        "owner": "tinted-theming",
-        "repo": "tinted-kitty",
-        "type": "github"
-      }
-    },
-    "tinted-schemes": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1781968807,
-        "narHash": "sha256-yYO3Vw2M0y3TAUqt+9+Mj0zwP3XDTF5/PXcPhhFQ1ZM=",
-        "owner": "tinted-theming",
-        "repo": "schemes",
-        "rev": "2ccef2f4b22e3cab5a9292811f7133a07eeba4a7",
-        "type": "github"
-      },
-      "original": {
-        "owner": "tinted-theming",
-        "repo": "schemes",
-        "type": "github"
-      }
-    },
-    "tinted-tmux": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1782012462,
-        "narHash": "sha256-2iDiD8DQLwS1lGuD9TS8WlvNyDoTs6krWntJbtB2zGo=",
-        "owner": "tinted-theming",
-        "repo": "tinted-tmux",
-        "rev": "8c4e750f738a742bd73377ee41d3dadedebedef4",
-        "type": "github"
-      },
-      "original": {
-        "owner": "tinted-theming",
-        "repo": "tinted-tmux",
-        "type": "github"
-      }
-    },
-    "tinted-zed": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1782009766,
-        "narHash": "sha256-VUhBjpGvWqHI7rWeyMYb/u87YJSXHKfVV6S+IelWeO8=",
-        "owner": "tinted-theming",
-        "repo": "base16-zed",
-        "rev": "5e8350bcd354e3241ab681a265fa6ef060c40be1",
-        "type": "github"
-      },
-      "original": {
-        "owner": "tinted-theming",
-        "repo": "base16-zed",
-        "type": "github"
-      }
     }
   },
   "root": "root",

flake.nix

@@ -2,10 +2,8 @@
   description = "Alexion's NixOS configuration — one flake for every host";
 
   inputs = {
-    monorepo.url = "path:/home/alexion/dev";
-
-    # Base package set shared with the monorepo.
-    nixpkgs.follows = "monorepo/nixpkgs";
+    # Base channel.
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
 
     # Fresher packages, reachable per-package as `unstable.<name>`.
     nixpkgs-unstable.url = "github:nixos/nixpkgs/nixpkgs-unstable";
@@ -18,27 +16,19 @@
       inputs.nixpkgs.follows = "nixpkgs";
     };
 
-    # Signed AMO extensions, pinned by version and hash.
-    firefox-addons = {
-      url = "gitlab:rycee/nur-expressions?dir=pkgs/firefox-addons";
-      inputs.nixpkgs.follows = "nixpkgs";
-    };
-
     # Follows our nixpkgs so its plugins build against the same package set.
     nixvim = {
       url = "github:nix-community/nixvim";
       inputs.nixpkgs.follows = "nixpkgs";
     };
 
-    # Declarative disk partitioning.
-    # Each host declares its own layout.
+    # Declarative disk partitioning; each host declares its own layout.
     disko = {
       url = "github:nix-community/disko";
       inputs.nixpkgs.follows = "nixpkgs";
     };
 
-    # Upstream per-machine hardware profiles.
-    # Each host imports its own.
+    # Upstream per-machine hardware profiles; each host imports its own.
     nixos-hardware = {
       url = "github:NixOS/nixos-hardware";
       inputs.nixpkgs.follows = "nixpkgs";
@@ -50,27 +40,15 @@
       inputs.nixpkgs.follows = "nixpkgs";
     };
 
-    # Themes the graphical layer from one base16 scheme.
-    # Follows our nixpkgs so it themes the same package set the host builds.
-    stylix = {
-      url = "github:danth/stylix";
-      inputs.nixpkgs.follows = "nixpkgs";
-    };
-
-    # Agent-ergonomic CLI for Gitea, with a home-manager module for the agent context.
+    # Agent-ergonomic CLI for Gitea, with its home-manager module wiring in the
+    # Claude Code context where that harness is present.
     gitea-axi = {
       url = "git+https://git.alexion.dev/alexion/gitea-axi";
       inputs.nixpkgs.follows = "nixpkgs";
     };
 
-    # Personal agent skills, packaged as per-skill derivations with a home-manager module.
-    skills = {
-      url = "git+https://git.alexion.dev/alexion/skills";
-      inputs.nixpkgs.follows = "nixpkgs";
-    };
-
-    # CachyOS kernel and binary cache.
-    # Pins its own nixpkgs so its cache stays usable and the kernel is fetched from it.
+    # CachyOS kernel and binary cache. Pins its own nixpkgs so its cache stays
+    # usable and the kernel is fetched from it.
     chaotic.url = "github:chaotic-cx/nyx/nyxpkgs-unstable";
   };
 
@@ -78,30 +56,18 @@
     { self, nixpkgs, ... }@inputs:
     let
       inherit (nixpkgs) lib;
+      my = import ./lib.nix { inherit lib inputs self; };
     in
     {
-      inherit (import ./flake { inherit lib inputs self; }) nixosConfigurations;
+      # Helper functions for discovering and building hosts.
+      lib = my;
 
-      # A project shell for agent-local resources that should travel with this
-      # checkout rather than the operator's global profile.
-      devShells.x86_64-linux.default =
-        let
-          pkgs = nixpkgs.legacyPackages.x86_64-linux;
-        in
-        pkgs.mkShell {
-          packages = [ inputs.gitea-axi.packages.x86_64-linux.gitea-axi ];
-          shellHook = inputs.skills.lib.mkSkillsShellHook [
-            inputs.gitea-axi.packages.x86_64-linux.gitea-axi-skill
-          ];
-        };
+      # Every host under hosts/ is discovered and built.
+      nixosConfigurations = my.mkHosts (self + "/hosts");
 
-      # `nix flake check` builds every discovered host toplevel.
+      # `nix flake check` builds each host's toplevel.
       checks.x86_64-linux = lib.mapAttrs (
-        name: host:
-        if host.config.warnings == [ ] then
-          host.config.system.build.toplevel
-        else
-          throw "Host ${name} has evaluation warnings:\n${lib.concatStringsSep "\n" host.config.warnings}"
+        _name: host: host.config.system.build.toplevel
       ) self.nixosConfigurations;
     };
 }

flake/default.nix

@@ -1,53 +0,0 @@
-{
-  lib,
-  inputs,
-  self,
-}:
-let
-  util = import ../lib { inherit lib; };
-
-  registry = import ./registry.nix {
-    inherit lib;
-    hosts = self.nixosConfigurations;
-    root = self + "/registry";
-  };
-
-  modules = import ./module.nix {
-    inherit util;
-    root = self + "/modules";
-  };
-
-  guestModules = import ./guest.nix {
-    inherit
-      inputs
-      lib
-      registry
-      specialArgs
-      util
-      ;
-    repositoryModules = modules;
-    root = self + "/guests";
-  };
-
-  specialArgs = {
-    inherit
-      inputs
-      self
-      util
-      ;
-    registry = registry.collected;
-  };
-in
-{
-  nixosConfigurations = import ./host.nix {
-    inherit
-      inputs
-      lib
-      specialArgs
-      guestModules
-      ;
-    registryModule = registry.module;
-    repositoryModules = modules;
-    root = self + "/hosts";
-  };
-}

flake/guest.nix

@@ -1,279 +0,0 @@
-{
-  inputs,
-  lib,
-  root,
-  specialArgs,
-  repositoryModules,
-  registry,
-  util,
-}:
-let
-  mkGuest =
-    name:
-    { config, lib, ... }:
-    let
-      cfg = config.guests.${name};
-
-      directoryMounts = lib.filterAttrs (_: mount: mount.directory != null) cfg.mounts;
-
-      directoryScript = lib.concatStringsSep "\n" (
-        lib.mapAttrsToList (
-          _: mount:
-          ''
-            ${config.system.path}/bin/install -d \
-              ${lib.optionalString (mount.owner != null) "-o ${lib.escapeShellArg (toString mount.owner)}"} \
-              ${lib.optionalString (mount.group != null) "-g ${lib.escapeShellArg mount.group}"} \
-              ${lib.optionalString (mount.mode != null) "-m ${lib.escapeShellArg mount.mode}"} \
-              ${lib.escapeShellArg mount.directory}
-          ''
-        ) directoryMounts
-      );
-    in
-    {
-      options.guests.${name} = {
-        enable = lib.mkEnableOption "the ${name} guest, run in its own nested container";
-        vlan = lib.mkOption {
-          type = lib.types.ints.between 1 4094;
-          example = 10;
-          description = ''
-            The tagged VLAN this guest lives on. The guest attaches to its host's
-            `br-vlan<id>` bridge for that VLAN. The id must be one of the host's
-            `modules.network.vlans.ids`.
-          '';
-        };
-        mac = lib.mkOption {
-          type = lib.types.str;
-          default = util.deriveMac "${config.networking.hostName}.${name}";
-          defaultText = lib.literalMD "a stable address derived from the host name and guest option path";
-          example = "bc:24:11:00:00:01";
-          description = ''
-            The guest's MAC address on its VLAN, pinned inside the guest by its
-            own networkd. Set it to reuse an existing address so a router's DHCP
-            reservation keeps working. Left unset, a stable address is derived
-            from the host name and guest option path in the locally-administered range.
-          '';
-        };
-        address = lib.mkOption {
-          type = lib.types.nullOr lib.types.str;
-          default = null;
-          example = "10.23.20.126";
-          description = ''
-            Expected IP address assigned outside NixOS for this guest.
-            Left null, this guest contributes no address to the address registry.
-          '';
-        };
-        reverseProxy = {
-          enable = lib.mkEnableOption "a reverse-proxy route for this guest";
-
-          route = lib.mkOption {
-            type = registry.types.route;
-            description = "Route registry entry published for this guest.";
-          };
-        };
-        mounts = lib.mkOption {
-          type = lib.types.attrsOf (
-            lib.types.submodule {
-              options = {
-                directory = lib.mkOption {
-                  type = lib.types.nullOr lib.types.str;
-                  default = null;
-                  example = "/srv/media";
-                  description = "Host directory bind-mounted into the guest.";
-                };
-                file = lib.mkOption {
-                  type = lib.types.nullOr lib.types.str;
-                  default = null;
-                  example = "/run/secrets/service-password";
-                  description = "Host file bind-mounted into the guest.";
-                };
-                readOnly = lib.mkOption {
-                  type = lib.types.bool;
-                  default = false;
-                  description = "Mount the host path read-only inside the guest.";
-                };
-                owner = lib.mkOption {
-                  type = lib.types.nullOr (
-                    lib.types.oneOf [
-                      lib.types.str
-                      lib.types.ints.positive
-                    ]
-                  );
-                  default = null;
-                  description = "Owner assigned to the host directory before the guest starts.";
-                };
-                group = lib.mkOption {
-                  type = lib.types.nullOr lib.types.str;
-                  default = null;
-                  description = "Group assigned to the host directory before the guest starts.";
-                };
-                mode = lib.mkOption {
-                  type = lib.types.nullOr lib.types.str;
-                  default = null;
-                  example = "0770";
-                  description = "Mode assigned to the host directory before the guest starts.";
-                };
-              };
-            }
-          );
-          default = { };
-          example = lib.literalExpression ''
-            {
-              "/data/media" = { directory = "/srv/media"; };
-              "/data/config" = { directory = "/srv/config/jellyfin"; };
-            }
-          '';
-          description = ''
-            Host paths bind-mounted into the guest, keyed by the path they appear
-            at inside the guest, so a guest sees exactly the data it should at any
-            granularity — a single folder, a whole pool, or a decrypted secret.
-            Mounts are read-write unless `readOnly` is set.
-          '';
-        };
-        interior = lib.mkOption {
-          type = lib.types.deferredModule;
-          default = { };
-          description = "NixOS module imported into the guest interior.";
-        };
-        limits = {
-          memory = lib.mkOption {
-            type = lib.types.nullOr lib.types.str;
-            default = null;
-            example = "2G";
-            description = ''
-              Cap on the guest's memory, applied to its unit as `MemoryMax`.
-              Accepts systemd size suffixes such as `512M` or `2G`. Left null,
-              the guest's memory is uncapped.
-            '';
-          };
-          cpu = lib.mkOption {
-            type = lib.types.nullOr lib.types.str;
-            default = null;
-            example = "150%";
-            description = ''
-              Cap on the guest's CPU, applied to its unit as `CPUQuota`, where
-              `100%` is one full core. Left null, the guest's CPU is uncapped.
-            '';
-          };
-          tasksMax = lib.mkOption {
-            type = lib.types.nullOr lib.types.ints.positive;
-            default = null;
-            example = 512;
-            description = ''
-              Cap on the number of processes and threads the guest may spawn,
-              applied to its unit as `TasksMax`. Left null, the task count is
-              uncapped.
-            '';
-          };
-        };
-      };
-
-      config = lib.mkIf cfg.enable {
-        assertions =
-          let
-            hasDirectorySettings = mount: mount.owner != null || mount.group != null || mount.mode != null;
-            hasCompleteDirectorySettings = mount: mount.owner != null && mount.group != null && mount.mode != null;
-            hasOneSource = mount: (mount.directory != null) != (mount.file != null);
-            mountsWithInvalidSource = lib.attrNames (lib.filterAttrs (_: mount: !hasOneSource mount) cfg.mounts);
-            fileMountsWithHostSettings = lib.attrNames (
-              lib.filterAttrs (_: mount: mount.file != null && hasDirectorySettings mount) cfg.mounts
-            );
-            directoryMountsWithPartialHostSettings = lib.attrNames (
-              lib.filterAttrs (_: mount: mount.directory != null && hasDirectorySettings mount && !hasCompleteDirectorySettings mount) cfg.mounts
-            );
-          in
-          [
-            {
-              assertion = mountsWithInvalidSource == [ ];
-              message = ''
-                guests.${name} mounts ${lib.concatStringsSep ", " mountsWithInvalidSource} must set exactly one of `directory` or `file`.
-              '';
-            }
-            {
-              assertion = fileMountsWithHostSettings == [ ];
-              message = ''
-                guests.${name} file mounts ${lib.concatStringsSep ", " fileMountsWithHostSettings} must not set `owner`, `group`, or `mode`.
-              '';
-            }
-            {
-              assertion = directoryMountsWithPartialHostSettings == [ ];
-              message = ''
-                guests.${name} directory mounts ${lib.concatStringsSep ", " directoryMountsWithPartialHostSettings} must set `owner`, `group`, and `mode` together.
-              '';
-            }
-            {
-              assertion = lib.elem cfg.vlan config.modules.network.vlans.ids;
-              message = ''
-                guests.${name}.vlan = ${toString cfg.vlan} is not among its host's modules.network.vlans.ids (${lib.concatMapStringsSep ", " toString config.modules.network.vlans.ids}). Declare the VLAN on the host or correct the guest's placement.
-              '';
-            }
-          ];
-
-        registry.address.${config.networking.hostName}.${name} =
-          lib.mkIf (cfg.address != null) cfg.address;
-
-        registry.route.${config.networking.hostName}.${name} =
-          lib.mkIf cfg.reverseProxy.enable cfg.reverseProxy.route;
-
-        systemd.services."container@${name}" =
-          let
-            bridgeDevice = "sys-subsystem-net-devices-${lib.replaceStrings [ "-" ] [ "\\x2d" ] (util.bridgeName cfg.vlan)}.device";
-          in
-          {
-            after = [ bridgeDevice ];
-            wants = [ bridgeDevice ];
-
-            serviceConfig = lib.filterAttrs (_: v: v != null) {
-              MemoryMax = cfg.limits.memory;
-              CPUQuota = cfg.limits.cpu;
-              TasksMax = cfg.limits.tasksMax;
-            };
-            preStart = lib.mkIf (directoryMounts != { }) directoryScript;
-          };
-
-        containers.${name} = {
-          autoStart = true;
-          privateNetwork = lib.mkDefault true;
-          hostBridge = util.bridgeName cfg.vlan;
-          privateUsers = lib.mkDefault "no";
-          bindMounts = lib.mapAttrs (_: mount: {
-            hostPath = if mount.directory != null then mount.directory else mount.file;
-            isReadOnly = mount.readOnly;
-          }) cfg.mounts;
-
-          inherit specialArgs;
-
-          config = {
-            imports = [
-              inputs.sops-nix.nixosModules.sops
-              inputs.stylix.nixosModules.stylix
-
-              repositoryModules
-              registry.module
-              cfg.interior
-
-              {
-                modules.guest.enable = true;
-
-                networking.useNetworkd = true;
-                networking.useHostResolvConf = false;
-
-                systemd.network.networks."20-eth0" = {
-                  matchConfig.Name = "eth0";
-                  linkConfig.MACAddress = cfg.mac;
-                  networkConfig.DHCP = "yes";
-                };
-              }
-            ];
-          };
-        };
-      };
-    };
-in
-let
-  files = util.collectNixFiles root;
-  guestFiles = lib.filterAttrs (file: type: type == "regular" && lib.hasSuffix ".nix" file) (builtins.readDir root);
-  names = map (file: lib.removeSuffix ".nix" file) (lib.attrNames guestFiles);
-in
-{
-  imports = files ++ map mkGuest names;
-}

flake/host.nix

@@ -1,45 +0,0 @@
-{
-  inputs,
-  lib,
-  root,
-  specialArgs,
-  repositoryModules,
-
-  guestModules,
-  registryModule,
-}:
-let
-  mkHost =
-    {
-      root,
-      name,
-    }:
-    lib.nixosSystem {
-      inherit specialArgs;
-      modules = [
-        inputs.chaotic.nixosModules.default
-        inputs.disko.nixosModules.disko
-        inputs.sops-nix.nixosModules.sops
-        inputs.stylix.nixosModules.stylix
-
-        repositoryModules
-        guestModules
-
-        # TODO: refactor
-        registryModule (root + "/${name}")
-
-        {
-          networking.hostName = name;
-          modules.host.enable = true;
-        }
-      ];
-    };
-in
-let
-  directories = lib.filterAttrs (_name: type: type == "directory") (builtins.readDir root);
-  names = lib.attrNames directories;
-in
-lib.genAttrs names (
-  name:
-  mkHost { inherit root name; }
-)

flake/module.nix

@@ -1,7 +0,0 @@
-{
-  root,
-  util,
-}:
-{
-  imports = util.collectNixFiles root;
-}

flake/registry.nix

@@ -1,197 +0,0 @@
-{ hosts, lib, root }:
-let
-  checkType = lib.types.submodule {
-    options = {
-      assertion = lib.mkOption {
-        type = lib.types.functionTo lib.types.bool;
-        description = ''
-          Predicate run against this registry's flattened collected entries.
-        '';
-      };
-
-      message = lib.mkOption {
-        type = lib.types.str;
-        description = ''
-          Error message shown when this registry validation check fails.
-        '';
-      };
-    };
-  };
-
-  predicates = {
-    uniqueValue = value: entries: builtins.length (lib.unique (map value entries)) == builtins.length entries;
-  };
-
-  registryLib = lib // {
-    registry = (lib.registry or { }) // {
-      inherit predicates;
-    };
-  };
-
-  registryDefinitionModule = {
-    options = {
-      type = lib.mkOption {
-        type = lib.types.raw;
-        description = ''
-          NixOS option type for one registry entry.
-        '';
-      };
-
-      replicate = lib.mkOption {
-        type = lib.types.bool;
-        default = false;
-        description = ''
-          Whether collected entries are merged and published under every host key.
-        '';
-      };
-
-      checks = lib.mkOption {
-        type = lib.types.listOf checkType;
-        default = [ ];
-        description = ''
-          Validation checks for this registry's flattened collected entries.
-        '';
-      };
-    };
-  };
-
-  registryName = fileName: lib.removeSuffix ".nix" fileName;
-
-  registryOption = registry: lib.mkOption {
-    type = lib.types.attrsOf (lib.types.attrsOf registry.type);
-    default = { };
-    description = ''
-      Lazily collected fleet-visible registry entries, nested by host and entry name.
-    '';
-  };
-
-  mkRegistry = path:
-    let
-      evaluated = lib.evalModules {
-        specialArgs.lib = registryLib;
-        modules = [
-          registryDefinitionModule
-          path
-        ];
-      };
-    in
-    {
-      inherit (evaluated.config) type replicate checks;
-    };
-
-  definitions = lib.mapAttrs' (
-    name: type:
-    let
-      path = root + "/${name}";
-    in
-    lib.nameValuePair (registryName name) (mkRegistry path)
-  ) (lib.filterAttrs (name: type: type == "regular" && lib.hasSuffix ".nix" name) (builtins.readDir root));
-
-  flattenRegistryEntries = registryName: data:
-    lib.concatLists (
-      lib.mapAttrsToList (
-        host: entries:
-        lib.mapAttrsToList (entry: value: {
-          path = "registry.${registryName}.${host}.${entry}";
-          inherit host entry value;
-        }) entries
-      ) data
-    );
-
-  rawDeclarations = registryName: hosts:
-    lib.mapAttrs (_hostName: host: host.config.registry.${registryName} or { }) hosts;
-
-  replicatedEntries = registryName: raw:
-    let
-      entries = lib.concatLists (
-        lib.concatLists (
-          lib.mapAttrsToList (
-            _evalHost: hostDeclarations:
-            lib.mapAttrsToList (
-              hostName: declarations:
-              lib.mapAttrsToList (entryName: value: {
-                path = "registry.${registryName}.${hostName}.${entryName}";
-                inherit entryName value;
-              }) declarations
-            ) hostDeclarations
-          ) raw
-        )
-      );
-    in
-    lib.foldl' (
-      acc: entry:
-      if lib.hasAttr entry.entryName acc then
-        if acc.${entry.entryName}.value == entry.value then
-          acc
-        else
-          throw "conflicting replicated registry entry ${entry.path} does not match ${acc.${entry.entryName}.path}"
-      else
-        acc // {
-          ${entry.entryName} = entry;
-        }
-    ) { } entries;
-
-  replicatedData = registryName: hosts: raw:
-    let
-      entries = lib.mapAttrs (_entryName: entry: entry.value) (replicatedEntries registryName raw);
-    in
-    lib.mapAttrs (_hostName: _host: entries) hosts;
-
-  validationAssertions = data:
-    lib.concatLists (
-      lib.mapAttrsToList (
-        registryName: registry:
-        let
-          entries = flattenRegistryEntries registryName data.${registryName};
-        in
-        map (check: {
-          assertion = check.assertion entries;
-          inherit (check) message;
-        }) registry.checks
-      ) definitions
-    );
-
-  assertValid = data:
-    let
-      assertions = validationAssertions data;
-      failures = lib.filter (assertion: !assertion.assertion) assertions;
-    in
-    assert lib.assertMsg (lib.all (assertion: assertion.assertion) assertions) (
-      lib.concatMapStringsSep "\n" (assertion: assertion.message) failures
-    );
-    data;
-
-  join = registry: host: entry:
-    lib.filterAttrs (_name: value: value != null) (
-      lib.mapAttrs (registryName: _registry: (registry.${registryName}.${host} or { }).${entry} or null) definitions
-    );
-
-  collectData =
-    { hosts }:
-    let
-      raw = lib.mapAttrs (registryName: _registry: rawDeclarations registryName hosts) definitions;
-      data = lib.mapAttrs (
-        registryName: registry:
-        if registry.replicate or false then
-          replicatedData registryName hosts raw.${registryName}
-        else
-          lib.mapAttrs (hostName: host: host.config.registry.${registryName}.${hostName} or { }) hosts
-      ) definitions;
-    in
-    assertValid data;
-
-  withOperations = registry:
-    registry
-    // {
-      join = host: entry: join registry host entry;
-    };
-in
-{
-  types = lib.mapAttrs (_name: definition: definition.type) definitions;
-
-  module = {
-    options.registry = lib.mapAttrs (_name: registry: registryOption registry) definitions;
-  };
-
-  collected = withOperations (collectData { inherit hosts; });
-}

guests/actualbudget.nix

@@ -1,43 +0,0 @@
-{
-  config,
-  lib,
-  ...
-}:
-let
-  cfg = config.guests.actualbudget;
-  dataDir = "/data";
-in
-{
-  options.guests.actualbudget = {
-    dataPath = lib.mkOption {
-      type = lib.types.nullOr lib.types.str;
-      default = null;
-      example = "/srv/actualbudget";
-      description = "Host path bind-mounted as Actual Budget's data directory.";
-    };
-  };
-
-  config = lib.mkIf cfg.enable {
-    assertions = [
-      {
-        assertion = cfg.dataPath != null;
-        message = "guests.actualbudget.dataPath must point at the host directory that stores Actual Budget data.";
-      }
-    ];
-
-    guests.actualbudget = {
-      interior = {
-        modules.services.actualbudget = {
-          enable = true;
-          inherit dataDir;
-        };
-      };
-      mounts.${dataDir}.directory = cfg.dataPath;
-      limits = {
-        memory = lib.mkDefault "2G";
-        cpu = lib.mkDefault "200%";
-        tasksMax = lib.mkDefault 512;
-      };
-    };
-  };
-}

guests/copyparty.nix

@@ -1,128 +0,0 @@
-{
-  config,
-  lib,
-  ...
-}:
-let
-  cfg = config.guests.copyparty;
-
-  volumeType = lib.types.submodule {
-    options = {
-      hostPath = lib.mkOption {
-        type = lib.types.str;
-        description = "Host path bind-mounted into the Copyparty guest for this volume.";
-      };
-
-      path = lib.mkOption {
-        type = lib.types.str;
-        description = "Guest path served by this Copyparty volume.";
-      };
-
-      access = lib.mkOption {
-        type = lib.types.attrsOf (lib.types.listOf lib.types.str);
-        default = { };
-        description = "Copyparty access map from permission string to account names.";
-      };
-
-      flags = lib.mkOption {
-        type = lib.types.listOf lib.types.str;
-        default = [ ];
-        description = "Copyparty volume flags.";
-      };
-    };
-  };
-in
-{
-  options.guests.copyparty = {
-    accountName = lib.mkOption {
-      type = lib.types.str;
-      default = "alexion";
-      description = "Copyparty account name configured for password authentication.";
-    };
-
-    passwordSecret = lib.mkOption {
-      type = lib.types.str;
-      default = "services/copyparty/users/alexion/password";
-      description = "SOPS secret name containing the Copyparty account password.";
-    };
-
-    stateDir = lib.mkOption {
-      type = lib.types.str;
-      default = "/var/lib/copyparty";
-      description = "Guest path where Copyparty stores service state.";
-    };
-
-    statePath = lib.mkOption {
-      type = lib.types.nullOr lib.types.str;
-      default = null;
-      example = "/srv/copyparty";
-      description = "Host path bind-mounted as Copyparty's state directory.";
-    };
-
-    reverseProxy.trustedSources = lib.mkOption {
-      type = lib.types.listOf lib.types.str;
-      default = [ ];
-      description = "IP ranges that may supply Copyparty's forwarded client IP header.";
-    };
-
-    volumes = lib.mkOption {
-      type = lib.types.attrsOf volumeType;
-      default = { };
-      description = "Copyparty volumes keyed by their URL path.";
-    };
-  };
-
-  config = lib.mkIf cfg.enable {
-    assertions = [
-      {
-        assertion = cfg.statePath != null;
-        message = "guests.copyparty.statePath must point at the host directory that stores Copyparty state.";
-      }
-      {
-        assertion = cfg.volumes != { };
-        message = "guests.copyparty.volumes must declare the host's served Copyparty volumes.";
-      }
-    ];
-
-    guests.copyparty = {
-      interior.modules.services.copyparty = {
-        enable = true;
-        inherit (cfg) accountName stateDir;
-        passwordFile = "/run/secrets/${cfg.passwordSecret}";
-        reverseProxy = {
-          enable = cfg.reverseProxy.enable;
-          inherit (cfg.reverseProxy) trustedSources;
-        };
-        volumes = lib.mapAttrs (_urlPath: volume: {
-          inherit (volume) path access flags;
-        }) cfg.volumes;
-      };
-
-      mounts =
-        {
-          ${cfg.stateDir} = {
-            directory = cfg.statePath;
-            owner = config.registry."stable-uid".${config.networking.hostName}.copyparty;
-            group = "storage";
-            mode = "0770";
-          };
-          ${"/run/secrets/${cfg.passwordSecret}"} = {
-            file = config.sops.secrets.${cfg.passwordSecret}.path;
-            readOnly = true;
-          };
-        }
-        // lib.mapAttrs' (_urlPath: volume: lib.nameValuePair volume.path { directory = volume.hostPath; }) cfg.volumes;
-      limits = {
-        memory = lib.mkDefault "2G";
-        cpu = lib.mkDefault "200%";
-        tasksMax = lib.mkDefault 512;
-      };
-    };
-
-    sops.secrets.${cfg.passwordSecret} = {
-      owner = "root";
-      group = "storage";
-      mode = "0440";
-    };
-  };
-}

guests/reverse-proxy.nix

@@ -1,75 +0,0 @@
-{
-  config,
-  lib,
-  ...
-}:
-let
-  giteaSshBackend = "10.23.20.45:2022";
-in
-{
-  config = lib.mkIf config.guests.reverse-proxy.enable {
-    guests.reverse-proxy = {
-      interior = {
-        modules.services.reverse-proxy.enable = true;
-
-        services.nginx.virtualHosts = {
-          "games.alexion.dev" = {
-            forceSSL = true;
-            enableACME = true;
-            locations."/".proxyPass = "http://10.23.20.32";
-          };
-          "git.alexion.dev" = {
-            forceSSL = true;
-            enableACME = true;
-            locations."/".proxyPass = "http://10.23.20.32";
-          };
-          "music.alexion.dev" = {
-            forceSSL = true;
-            enableACME = true;
-            locations."/".proxyPass = "http://10.23.20.32";
-          };
-          "photos.alexion.dev" = {
-            forceSSL = true;
-            enableACME = true;
-            locations."/".proxyPass = "http://10.23.20.32";
-          };
-          "plex.alexion.dev" = {
-            forceSSL = true;
-            enableACME = true;
-            locations."/".proxyPass = "http://10.23.20.32";
-          };
-          "servers.alexion.dev" = {
-            forceSSL = true;
-            enableACME = true;
-            locations."/".proxyPass = "http://10.23.20.32";
-          };
-          "todo.alexion.dev" = {
-            forceSSL = true;
-            enableACME = true;
-            locations."/".proxyPass = "http://10.23.20.32";
-          };
-          "wings.alexion.dev" = {
-            forceSSL = true;
-            enableACME = true;
-            locations."/".proxyPass = "http://10.23.20.32";
-          };
-        };
-
-        networking.firewall.allowedTCPPorts = [ 2022 ];
-
-        services.nginx.streamConfig = ''
-          server {
-            listen 2022;
-            proxy_pass ${giteaSshBackend};
-          }
-        '';
-      };
-
-      limits = {
-        memory = lib.mkDefault "1G";
-        cpu = lib.mkDefault "100%";
-        tasksMax = lib.mkDefault 256;
-      };
-    };
-  };
-}

hosts/neogaia/default.nix

@@ -1,11 +1,11 @@
 {
+  config,
   inputs,
   pkgs,
   ...
 }:
 # neogaia — Dell XPS 13 9380 laptop.
-# Disk layout is in ./disk.nix.
-# `fileSystems` are derived from it, none declared here.
+# Disk layout is in ./disk.nix; `fileSystems` are derived from it, none declared here.
 {
   imports = [
     inputs.nixos-hardware.nixosModules.dell-xps-13-9380
@@ -22,31 +22,35 @@
   boot.kernelPackages = pkgs.linuxPackages_cachyos;
 
   # Redistributable firmware for the QCA6174 wifi (ath10k blobs).
-  # Intel microcode updates follow from this, so none is declared here.
+  # Intel microcode updates follow from this; none declared here.
   hardware.enableRedistributableFirmware = true;
 
-  # RAM-backed swap, no on-disk swap partition.
+  # RAM-backed swap; no on-disk swap partition.
   zramSwap.enable = true;
 
   # So wifi can be joined from the console.
   networking.networkmanager.enable = true;
 
-  registry.address.neogaia.self = "10.23.50.146";
-
   # So setup can be driven over the network.
   # The matching host public keys sit beside this file in plaintext, since
   # publishing them is their purpose.
-  modules.network.ssh.enable = true;
-  modules.network.ssh.hostKeys.sopsFile = ../../secrets/neogaia.yaml;
-  modules.network.ssh.userKey.sopsFile = ../../secrets/neogaia.yaml;
+  modules.ssh.enable = true;
+  modules.ssh.hostKeys.sopsFile = ../../secrets/neogaia.yaml;
+  modules.ssh.userKey.sopsFile = ../../secrets/neogaia.yaml;
 
-  modules.shell.herdr.enable = true;
-  modules.agents.tools.gitea-axi.enable = true;
-  modules.agents.pi.enable = true;
+  # A machine the operator works from, so it admits the workstation keys alone.
+  modules.ssh.authorizedKeys = config.modules.ssh.workstationKeys;
 
-  modules.desktop.enable = true;
-  modules.desktop.apps.obsidian.enable = true;
-  modules.desktop.apps.steam.enable = true;
+  # fish as the login shell.
+  modules.fish.enable = true;
+  modules.fish.defaultShell = true;
+
+  modules.git.enable = true;
+  modules.tmux.enable = true;
+  modules.nvim.enable = true;
+  modules.claude-code.enable = true;
+  modules.gitea-axi.enable = true;
+  modules.pi.enable = true;
 
   time.timeZone = "America/New_York";
   i18n.defaultLocale = "en_GB.UTF-8";

hosts/neogaia/disk.nix

@@ -1,8 +1,7 @@
 { ... }:
 # neogaia's disk layout for disko: one NVMe disk, GPT, with an EFI system
-# partition and a LUKS container holding btrfs subvolumes.
-# No swap partition, since swap is zram.
-# disko derives `fileSystems` and `boot.initrd.luks.devices` from this.
+# partition and a LUKS container holding btrfs subvolumes. No swap partition;
+# swap is zram. disko derives `fileSystems` and `boot.initrd.luks.devices` from this.
 {
   disko.devices.disk.main = {
     type = "disk";
@@ -11,8 +10,8 @@
       type = "gpt";
       partitions = {
         ESP = {
-          # Each generation stores a kernel and initrd here and the CachyOS kernel is large.
-          # An exhausted partition fails bootloader installs.
+          # Each generation stores a kernel and initrd here and the CachyOS
+          # kernel is large; an exhausted partition fails bootloader installs.
           size = "2G";
           type = "EF00";
           content = {

hosts/neogaia/hardware-configuration.nix

@@ -1,6 +1,6 @@
 { lib, modulesPath, ... }:
 # Hardware detected by nixos-generate-config on this machine.
-# disko derives `fileSystems` and the LUKS device, none declared here.
+# disko derives `fileSystems` and the LUKS device; none declared here.
 {
   imports = [ (modulesPath + "/installer/scan/not-detected.nix") ];
 

hosts/pikachu/default.nix

@@ -1,149 +0,0 @@
-{
-  config,
-  pkgs,
-  registry,
-  ...
-}:
-# pikachu — AZW ME Pro server.
-# Disk layout is in ./disk.nix.
-# `fileSystems` for the root disk are derived from it.
-{
-  imports = [
-    ./hardware-configuration.nix
-    ./disk.nix
-  ];
-
-  system.stateVersion = "26.05";
-
-  boot.loader.systemd-boot.enable = true;
-  boot.loader.efi.canTouchEfiVariables = true;
-
-  hardware.cpu.intel.updateMicrocode = true;
-  hardware.enableRedistributableFirmware = true;
-
-  zramSwap.enable = true;
-
-  systemd.network = {
-    enable = true;
-    netdevs = {
-      "40-br-vlan20".netdevConfig = {
-        Name = "br-vlan20";
-        Kind = "bridge";
-      };
-      "40-vlan20" = {
-        netdevConfig = {
-          Name = "vlan20";
-          Kind = "vlan";
-        };
-        vlanConfig.Id = 20;
-      };
-    };
-
-    networks = {
-      "10-uplink" = {
-        matchConfig = {
-          Name = "enp2s0";
-          MACAddress = "78:55:36:07:af:49";
-        };
-        networkConfig.DHCP = "yes";
-        vlan = [ "vlan20" ];
-        linkConfig.RequiredForOnline = "routable";
-      };
-      "40-vlan20" = {
-        matchConfig.Name = "vlan20";
-        networkConfig.Bridge = "br-vlan20";
-        linkConfig.RequiredForOnline = "no";
-      };
-      "40-br-vlan20" = {
-        matchConfig.Name = "br-vlan20";
-        linkConfig.RequiredForOnline = "no";
-      };
-    };
-  };
-  networking.useDHCP = false;
-
-  modules.network.vlans.ids = [ 20 ];
-
-  boot.zfs.forceImportRoot = false;
-
-  modules.zfs = {
-    enable = true;
-    hostId = "2346edbd";
-    pools.pikachu = { };
-  };
-
-  registry.address.pikachu.self = "10.23.10.102";
-
-  modules.network.ssh.enable = true;
-  modules.network.ssh.hostKeys.sopsFile = ../../secrets/pikachu.yaml;
-  modules.network.ssh.userKey.sopsFile = ../../secrets/pikachu.yaml;
-
-  guests.actualbudget = {
-    enable = true;
-    vlan = 20;
-    mac = "BC:24:11:C1:CD:28";
-    dataPath = "/pikachu/data/actualbudget";
-    address = "10.23.20.42";
-    reverseProxy = {
-      enable = true;
-      route = {
-        domain = "budget.alexion.dev";
-        port = 5006;
-      };
-    };
-  };
-
-  guests.reverse-proxy = {
-    enable = true;
-    vlan = 20;
-    mac = "02:98:64:5a:07:4f";
-    address = "10.23.20.109";
-  };
-
-  guests.copyparty = {
-    enable = true;
-    vlan = 20;
-    mac = "02:23:20:39:23:01";
-    statePath = "/pikachu/data/copyparty";
-    address = "10.23.20.126";
-    reverseProxy = {
-      enable = true;
-      route = {
-        domain = "files.alexion.dev";
-        port = 3923;
-      };
-      trustedSources = [ "${registry.address.${config.networking.hostName}."reverse-proxy"}/32" ];
-    };
-    volumes = {
-      "/inbox" = {
-        hostPath = "/pikachu/__inbox";
-        path = "/srv/inbox";
-        access.A = [ "alexion" ];
-        flags = [
-          "d2d"
-          "d2t"
-          "dthumb"
-        ];
-      };
-      "/media" = {
-        hostPath = "/pikachu/media";
-        path = "/srv/media";
-        access.A = [ "alexion" ];
-        flags = [
-          "d2d"
-          "d2t"
-          "dthumb"
-        ];
-      };
-    };
-  };
-
-  environment.systemPackages = with pkgs; [
-    pciutils
-    smartmontools
-    usbutils
-  ];
-
-  time.timeZone = "America/New_York";
-  i18n.defaultLocale = "en_GB.UTF-8";
-}

hosts/pikachu/disk.nix

@@ -1,32 +0,0 @@
-{ ... }:
-# pikachu's install layout for disko: one NVMe boot disk with an EFI system partition and ext4 root.
-# The existing 8 TB ZFS mirror is imported by name and is never declared here.
-{
-  disko.devices.disk.main = {
-    type = "disk";
-    device = "/dev/nvme0n1";
-    content = {
-      type = "gpt";
-      partitions = {
-        ESP = {
-          size = "2G";
-          type = "EF00";
-          content = {
-            type = "filesystem";
-            format = "vfat";
-            mountpoint = "/boot";
-            mountOptions = [ "umask=0077" ];
-          };
-        };
-        root = {
-          size = "100%";
-          content = {
-            type = "filesystem";
-            format = "ext4";
-            mountpoint = "/";
-          };
-        };
-      };
-    };
-  };
-}

hosts/pikachu/hardware-configuration.nix

@@ -1,18 +0,0 @@
-{ lib, modulesPath, ... }:
-# Hardware detected from the Proxmox inventory for this machine.
-# disko derives the root disk filesystems, none declared here.
-{
-  imports = [ (modulesPath + "/installer/scan/not-detected.nix") ];
-
-  boot.initrd.availableKernelModules = [
-    "ahci"
-    "nvme"
-    "sd_mod"
-    "xhci_pci"
-  ];
-  boot.initrd.kernelModules = [ ];
-  boot.kernelModules = [ "kvm-intel" ];
-  boot.extraModulePackages = [ ];
-
-  nixpkgs.hostPlatform = lib.mkDefault "x86_64-linux";
-}

hosts/pikachu/ssh_host_ed25519_key.pub

@@ -1 +0,0 @@
-ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIKljRf4pJO+pqEqjpPz08gOYq3g1PpxvE66xVw7uMEnA root@pikachu

hosts/pikachu/ssh_host_rsa_key.pub

@@ -1 +0,0 @@
-ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAACAQCy/riwm7dflA3mT+3a0/2CIoS2LbAsK/vn35kOoNeuzn0yhiF+imexP6tkB3S2t+H5ybRzkbbuNZcynFfeCqthFc8kvbdCnt8Diqoeg96fZ6ecvh5QE5yH9op8534EySetZ/exakFLnF+6EiWMuWUW3DFwsc2kcgDJObqSE8gTx/d7JK953MiTFmSJBFyg1RtQ3ZnMT+iCrvY2dyCLQai7VeF8koVKF2c0leAq2Hc75rb/L9md8MoJa64iPiz7hwTCin3xoFyaY/5hNVvyqFd5PivgR69gLdJkuVsUYO2mJzhur8cYmJD+pGjJ0U45hyE9TMrCFjeJHHuvSt3+2kph62wv95jLNk0WmMlwgyunISxENCSVVtNYdBMXhUh8VhEAW17QpVUg9EnPvxOdTKEjrvfOZYASWUa51JKbgBgexVgFbxdjDZR88DZa31AVBts/cx/59gXTUahFXMYLdZgssx+5uibZQWnvCyfUV9WLbfmK1lgL6hzReg1VkQ87iGr6skjtQYemJxRaFNA1+Q5f3kmG3KncuK/594a3qXYP4gC6A2blf8om1YZ4aXXh6f+GFKLjoEw1vvM2rJ+rjzfymwDX+pxVQ9L13OEtVZc9Ez76pOkbm1hqdbL0gY45+0cpxodhWV0wMQJBDXL1MHP8qcs+/vw0GxVK5l1SnWBGlw== root@pikachu

lib.nix

@@ -0,0 +1,74 @@
+{
+  lib,
+  inputs,
+  self,
+}:
+let
+  inherit (lib)
+    attrNames
+    filterAttrs
+    genAttrs
+    flatten
+    hasSuffix
+    mapAttrsToList
+    ;
+
+  # Recursively collect every `.nix` file under `dir` as a flat list, for a
+  # module's `imports`.
+  collectNixFiles =
+    dir:
+    flatten (
+      mapAttrsToList (
+        name: type:
+        let
+          path = dir + "/${name}";
+        in
+        if type == "directory" then
+          collectNixFiles path
+        else if type == "regular" && hasSuffix ".nix" name then
+          [ path ]
+        else
+          [ ]
+      ) (builtins.readDir dir)
+    );
+
+  # Build one host: every module is imported unconditionally (inert until its
+  # `enable` flag is set), alongside home-manager, chaotic, the shared base, and
+  # the host's own directory.
+  mkHost =
+    {
+      hostName,
+      system ? "x86_64-linux",
+    }:
+    inputs.nixpkgs.lib.nixosSystem {
+      inherit system;
+      specialArgs = {
+        inherit inputs;
+        my = self.lib;
+      };
+      modules = (collectNixFiles (self + "/modules")) ++ [
+        inputs.home-manager.nixosModules.home-manager
+        inputs.chaotic.nixosModules.default
+        inputs.disko.nixosModules.disko
+        inputs.sops-nix.nixosModules.sops
+        (self + "/system.nix")
+        (self + "/hosts/${hostName}")
+        { networking.hostName = hostName; }
+      ];
+    };
+
+  # Discover every host (a subdirectory of `hostsDir`) and build each one.
+  mkHosts =
+    hostsDir:
+    let
+      hostNames = attrNames (filterAttrs (_name: type: type == "directory") (builtins.readDir hostsDir));
+    in
+    genAttrs hostNames (hostName: mkHost { inherit hostName; });
+in
+{
+  inherit
+    collectNixFiles
+    mkHost
+    mkHosts
+    ;
+}

lib/default.nix

@@ -1,9 +0,0 @@
-{ lib }:
-let
-  files = import ./files.nix { inherit lib; };
-  network = import ./network.nix { inherit lib; };
-in
-{
-  inherit (files) collectNixFiles;
-  inherit (network) bridgeName deriveMac;
-}

lib/files.nix

@@ -1,22 +0,0 @@
-{ lib }:
-let
-  collectNixFiles =
-    dir:
-    lib.flatten (
-      lib.mapAttrsToList (
-        name: type:
-        let
-          path = dir + "/${name}";
-        in
-        if type == "directory" then
-          collectNixFiles path
-        else if type == "regular" && lib.hasSuffix ".nix" name then
-          [ path ]
-        else
-          [ ]
-      ) (builtins.readDir dir)
-    );
-in
-{
-  inherit collectNixFiles;
-}

lib/network.nix

@@ -1,12 +0,0 @@
-{ lib }:
-{
-  bridgeName = id: "br-vlan${toString id}";
-
-  deriveMac =
-    name:
-    let
-      hash = builtins.hashString "sha256" name;
-      octet = i: builtins.substring (i * 2) 2 hash;
-    in
-    lib.concatStringsSep ":" ([ "02" ] ++ map octet [ 0 1 2 3 4 ]);
-}

modules/agents/context/AGENTS.md

@@ -1,85 +0,0 @@
-# Alexion's Agent Instructions
-
-These are common instructions for Alexion's agents across all scenarios.
-
-## General Guidelines
-
-- When writing commit messages, NEVER auto-add your agent name as co-author.
-  Omit the `Co-Authored-By:` trailer entirely, with no exceptions.
-  This overrides any default instruction to append one.
-- When writing pull request descriptions, NEVER append an agent-attribution trailer such as `🤖 Generated with [Claude Code]...`.
-  Leave it out entirely, with no exceptions.
-  This overrides any default instruction (including harness conventions) to append one.
-- NEVER ask the user a question using the `AskUserQuestion` tool.
-  Ask in plain prose, in your own message, instead, with no exceptions.
-  This overrides any default instruction (including harness conventions and skill instructions) to use it.
-- Never manually modify `CHANGELOG.md` files or files marked as auto-generated.
-  Detect auto-generated files with a layered check.
-  Trust an explicit in-file marker first, for example `AUTO-GENERATED, DO NOT EDIT`.
-  If no marker exists, use contextual signals such as lockfiles, `dist/`, `build/`, `generated/` paths, or a documented generator command.
-  If the answer stays ambiguous, ask before editing.
-- In authored prose, do not put multiple sentences on one physical line.
-  This applies to comments, documentation, user-facing descriptions, commit prose, pull-request prose, and forge comments.
-  A sentence can wrap across multiple physical lines when needed.
-- Keep Markdown formatting changes local.
-  Only format prose you write or change.
-  Never reflow an entire pre-existing paragraph or file because you touched nearby text.
-- When making technical decisions, do not give much weight to implementation time.
-  Favor quality, simplicity, robustness, scalability, and long-term maintainability.
-  Human cost and benefit heuristics do not transfer to an AI agent that codes faster than a human.
-  Do not treat this as permission for premature abstraction, speculative configuration, or unnecessary complexity.
-  Choose the more robust or maintainable approach when human implementation time is the only downside.
-- Use lowercase file names unless a valid reason requires uppercase.
-  Established ecosystem or tool conventions count as valid reasons.
-  Examples include `README.md`, `LICENSE`, `CHANGELOG.md`, `Makefile`, `Dockerfile`, and `.github/` files.
-- Do not end a response by promising or implying continuation unless the continuation is present in that same response.
-  Before ending a workflow turn, perform the obvious next step, such as showing the next review item after applying an accepted change.
-  If the workflow is paused, say that plainly instead of using a dangling transition like "continuing" or "next".
-- When you discover that your belief about a project fact or convention was wrong, record the correction.
-  Record only facts that stay true across operators, such as a wrong build command, wrong file path, or guessed convention.
-  Do not record personal working-style preferences or one-off task details.
-  Record the correction in the nearest project `AGENTS.md`, not this global file.
-  Use a dedicated `## Gotchas` section, and create that section when the file lacks one.
-  If no project `AGENTS.md` exists, ask before creating one.
-  Append the correction immediately without asking when a project `AGENTS.md` exists.
-  Briefly mention the edit in your response.
-  If an existing entry is wrong or stale, correct or remove it the same way.
-
-## Comments
-
-- Write comments only where they earn their place.
-  Keep comments concise.
-  Assume the reader can read code.
-  Explain why, not what.
-  Explain what only when it is genuinely non-obvious.
-- Keep comments self-contained to their file.
-  Write comments for a reader who sees only that file.
-  Do not explain how another file or tool consumes a value.
-  The only permitted cross-file mention is a bare pointer explaining why something is absent here.
-- Do not narrate history or future state in comments.
-  Avoid phrases such as "used to be", "now moved here", and "will be".
-  State the present reason a thing exists.
-- Do not justify a choice against alternatives in comments.
-  State the positive reason the choice exists.
-  Include present consequences when they matter.
-- Do not reference agent-facing state in comments.
-  This includes `.agents/`, `.claude/`, `AGENTS.md`, and `CLAUDE.md`.
-- Do not use project-specific capitalized terms as glossary references in comments.
-  Use plain lowercase nouns unless the code requires the exact term.
-- Add a file-top header only when the filename or path does not already explain the file.
-  The header must be one concise purpose line.
-  Do not write a feature inventory.
-- Write placeholders plainly.
-  Include a present-tense action when one exists, such as `Placeholder: regenerate with <tool> on the target machine`.
-  Do not write `placeholder for <missing feature>`.
-- Treat user-facing documentation strings as documentation, not comments.
-  They can describe behavior more fully than code comments.
-  They still must stay self-contained and avoid agent-state references.
-- Start each sentence of a comment on its own physical line.
-  A comment sentence can wrap when needed.
-  Prefer splitting long comment sentences before wrapping them.
-  Do not break a line early at a comma or clause boundary to make it read as a unit.
-  Do not use semicolons in comments or authored prose.
-  Recast semicolon clauses as separate sentences.
-  Only reformat comments you write or change.
-

modules/agents/context/context.nix

@@ -1,21 +0,0 @@
-{
-  config,
-  lib,
-  ...
-}:
-# Shared global instructions for agent harnesses.
-let
-  user = config.user.name;
-  context = builtins.readFile ./AGENTS.md;
-in
-{
-  config = lib.mkMerge [
-    (lib.mkIf config.modules.agents.claude-code.enable {
-      home-manager.users.${user}.programs.claude-code.context = context;
-    })
-
-    (lib.mkIf config.modules.agents.pi.enable {
-      home-manager.users.${user}.programs.pi-coding-agent.context = context;
-    })
-  ];
-}

modules/agents/pi/extensions/compact-status.ts

@@ -1,254 +0,0 @@
-import { execFileSync } from "node:child_process";
-import { existsSync, readFileSync } from "node:fs";
-import { homedir } from "node:os";
-import { basename, join } from "node:path";
-import type { ExtensionAPI } from "@earendil-works/pi-coding-agent";
-import { truncateToWidth, visibleWidth } from "@earendil-works/pi-tui";
-
-type QuotaState =
-  | { status: "idle" | "loading" }
-  | { status: "ok"; detail: string; refreshedAt: number; weeklyRemaining?: number; shortRemaining?: number }
-  | { status: "missing" | "error"; detail: string; refreshedAt?: number };
-
-const CODEX_USAGE_ENDPOINTS = [
-  "https://chatgpt.com/backend-api/wham/usage",
-  "https://chatgpt.com/backend-api/codex/usage",
-];
-const QUOTA_REFRESH_MS = 5 * 60 * 1000;
-const REQUEST_TIMEOUT_MS = 10_000;
-
-let quotaState: QuotaState = { status: "idle" };
-let quotaRefreshPromise: Promise<void> | null = null;
-
-function shortCwd(cwd: string): string {
-  const home = process.env.HOME;
-  if (home && cwd.startsWith(`${home}/`)) return `~/${basename(cwd)}`;
-  return basename(cwd) || cwd;
-}
-
-function gitBranch(cwd: string): string | null {
-  try {
-    const out = execFileSync("git", ["--no-optional-locks", "symbolic-ref", "--quiet", "--short", "HEAD"], {
-      cwd,
-      encoding: "utf8",
-      stdio: ["ignore", "pipe", "ignore"],
-    }).trim();
-    return out || null;
-  } catch {
-    return null;
-  }
-}
-
-function authPath(): string {
-  return join(process.env.PI_CODING_AGENT_DIR ?? join(homedir(), ".pi", "agent"), "auth.json");
-}
-
-function readCodexCredentials(): { access: string; accountId?: string } | null {
-  const file = authPath();
-  if (!existsSync(file)) return null;
-  try {
-    const auth = JSON.parse(readFileSync(file, "utf8"));
-    const credential = auth?.["openai-codex"];
-    if (credential?.type !== "oauth" || typeof credential.access !== "string") return null;
-    if (typeof credential.expires === "number" && credential.expires <= Date.now() + 30_000) return null;
-    return {
-      access: credential.access,
-      accountId: typeof credential.accountId === "string" ? credential.accountId : undefined,
-    };
-  } catch {
-    return null;
-  }
-}
-
-function numberValue(value: unknown): number | undefined {
-  if (typeof value === "number" && Number.isFinite(value)) return value;
-  if (typeof value === "string" && value.trim() !== "") {
-    const parsed = Number(value);
-    if (Number.isFinite(parsed)) return parsed;
-  }
-  return undefined;
-}
-
-function objectValue(value: unknown): Record<string, unknown> | undefined {
-  return value && typeof value === "object" && !Array.isArray(value) ? (value as Record<string, unknown>) : undefined;
-}
-
-function windowSeconds(raw: Record<string, unknown>): number | undefined {
-  const seconds = numberValue(raw.limit_window_seconds ?? raw.windowSeconds);
-  if (seconds !== undefined) return seconds;
-  const mins = numberValue(raw.windowDurationMins ?? raw.window_duration_mins);
-  return mins === undefined ? undefined : mins * 60;
-}
-
-function usedPercent(raw: Record<string, unknown>): number | undefined {
-  const value = numberValue(raw.used_percent ?? raw.usedPercent);
-  if (value === undefined) return undefined;
-  return Math.max(0, Math.min(100, value));
-}
-
-function collectWindows(raw: unknown, out: Array<{ seconds?: number; used: number; key: string }> = [], key = "root") {
-  if (Array.isArray(raw)) {
-    raw.forEach((item, index) => collectWindows(item, out, `${key}.${index}`));
-    return out;
-  }
-  const obj = objectValue(raw);
-  if (!obj) return out;
-  const used = usedPercent(obj);
-  if (used !== undefined) out.push({ seconds: windowSeconds(obj), used, key });
-  for (const [childKey, value] of Object.entries(obj)) {
-    if (value && typeof value === "object") collectWindows(value, out, `${key}.${childKey}`);
-  }
-  return out;
-}
-
-function pickQuotaWindows(raw: unknown): { weeklyRemaining?: number; shortRemaining?: number } | null {
-  const windows = collectWindows(raw);
-  if (windows.length === 0) return null;
-  const weekly = windows.find((window) => window.seconds !== undefined && Math.abs(window.seconds - 604_800) <= 60 * 60)
-    ?? windows.find((window) => /week|weekly|secondary/i.test(window.key));
-  const short = windows.find((window) => window.seconds !== undefined && Math.abs(window.seconds - 18_000) <= 60 * 30)
-    ?? windows.find((window) => /five|session|primary|short/i.test(window.key));
-  return {
-    weeklyRemaining: weekly ? Math.max(0, Math.min(100, 100 - weekly.used)) : undefined,
-    shortRemaining: short ? Math.max(0, Math.min(100, 100 - short.used)) : undefined,
-  };
-}
-
-function safeFg(theme: any, color: string, text: string): string {
-  try {
-    return theme.fg(color, text);
-  } catch {
-    return theme.fg("accent", text);
-  }
-}
-
-function contextColor(percent: number): string {
-  if (percent >= 90) return "error";
-  if (percent >= 70) return "warning";
-  return "success";
-}
-
-function quotaColor(percent: number): string {
-  if (percent >= 80) return "error";
-  if (percent >= 50) return "warning";
-  return "border";
-}
-
-function bar(theme: any, width: number, percent: number | null, glyph: string, colorForPercent: (percent: number) => string): string {
-  const barWidth = Math.max(12, width);
-  if (percent === null) return theme.fg("muted", glyph.repeat(barWidth));
-  const clamped = Math.max(0, Math.min(100, percent));
-  const filled = Math.max(0, Math.min(barWidth, Math.round((clamped / 100) * barWidth)));
-  const empty = Math.max(0, barWidth - filled);
-  return safeFg(theme, colorForPercent(clamped), glyph.repeat(filled)) + theme.fg("dim", glyph.repeat(empty));
-}
-
-async function fetchCodexQuota(force = false): Promise<void> {
-  const fresh = quotaState.status === "ok" && Date.now() - quotaState.refreshedAt < QUOTA_REFRESH_MS;
-  if (!force && fresh) return;
-  if (quotaRefreshPromise) return quotaRefreshPromise;
-
-  quotaState = { status: "loading" };
-  quotaRefreshPromise = (async () => {
-    const credentials = readCodexCredentials();
-    if (!credentials) {
-      quotaState = { status: "missing", detail: "OpenAI Codex OAuth credentials were not found or are expired" };
-      return;
-    }
-
-    let lastError = "quota unavailable";
-    for (const endpoint of CODEX_USAGE_ENDPOINTS) {
-      const controller = new AbortController();
-      const timeout = setTimeout(() => controller.abort(), REQUEST_TIMEOUT_MS);
-      try {
-        const headers: Record<string, string> = { Authorization: `Bearer ${credentials.access}` };
-        if (credentials.accountId) headers["ChatGPT-Account-Id"] = credentials.accountId;
-        const response = await fetch(endpoint, { headers, signal: controller.signal });
-        if (!response.ok) {
-          lastError = `${response.status} ${response.statusText}`;
-          continue;
-        }
-        const windows = pickQuotaWindows(await response.json());
-        if (!windows || (windows.weeklyRemaining === undefined && windows.shortRemaining === undefined)) {
-          lastError = "response had no recognized quota windows";
-          continue;
-        }
-        const details = [];
-        if (windows.weeklyRemaining !== undefined) details.push(`weekly ${Math.round(windows.weeklyRemaining)}%`);
-        if (windows.shortRemaining !== undefined) details.push(`short ${Math.round(windows.shortRemaining)}%`);
-        quotaState = {
-          status: "ok",
-          detail: `Codex quota remaining: ${details.join(", ")}`,
-          weeklyRemaining: windows.weeklyRemaining,
-          shortRemaining: windows.shortRemaining,
-          refreshedAt: Date.now(),
-        };
-        return;
-      } catch (error) {
-        lastError = error instanceof Error ? error.message : String(error);
-      } finally {
-        clearTimeout(timeout);
-      }
-    }
-    quotaState = { status: "error", detail: `Codex quota failed: ${lastError}`, refreshedAt: Date.now() };
-  })().finally(() => {
-    quotaRefreshPromise = null;
-  });
-  return quotaRefreshPromise;
-}
-
-function statusLines(ctx: any, theme: any, width: number): string[] {
-  const cwd = ctx.sessionManager?.getCwd?.() ?? ctx.cwd ?? process.cwd();
-  const branch = gitBranch(cwd);
-  const where = branch ? `󰉋 ${shortCwd(cwd)} 󰘬 ${branch}` : `󰉋 ${shortCwd(cwd)}`;
-  const model = ctx.model?.id ?? process.env.PI_MODEL ?? "no-model";
-  const thinking = ctx.thinkingLevel ?? process.env.PI_REASONING_LEVEL ?? "off";
-  const left = theme.fg("accent", where);
-  const right = theme.fg("dim", `${model} • ${thinking}`);
-  const pad = " ".repeat(Math.max(1, width - visibleWidth(left) - visibleWidth(right)));
-  const contextPercentRaw = ctx.getContextUsage?.()?.percent;
-  const contextPercent = typeof contextPercentRaw === "number" && Number.isFinite(contextPercentRaw) ? contextPercentRaw : null;
-  const quotaConsumed = quotaState.status === "ok" && quotaState.weeklyRemaining !== undefined
-    ? 100 - quotaState.weeklyRemaining
-    : null;
-  return [
-    truncateToWidth(left + pad + right, width),
-    bar(theme, width, contextPercent, "▃", contextColor),
-    bar(theme, width, quotaConsumed, "▔", quotaColor),
-  ];
-}
-
-function setCompactStatusUi(ctx: any) {
-  if (!ctx.hasUI) return;
-  ctx.ui.setWidget("compact-status", (_tui: any, theme: any) => ({
-    invalidate() {},
-    render(width: number) {
-      return statusLines(ctx, theme, width);
-    },
-  }));
-  ctx.ui.setFooter(() => ({ invalidate() {}, render: () => [] }));
-}
-
-export default function compactStatus(pi: ExtensionAPI) {
-  function refreshUi(ctx: any) {
-    setCompactStatusUi(ctx);
-  }
-
-  pi.on("session_start", (_event, ctx) => {
-    refreshUi(ctx);
-    void fetchCodexQuota(false).then(() => refreshUi(ctx));
-  });
-  pi.on("model_select", (_event, ctx) => refreshUi(ctx));
-  pi.on("agent_settled", (_event, ctx) => refreshUi(ctx));
-
-  pi.registerCommand("codex-quota", {
-    description: "Refresh and show ChatGPT Codex quota",
-    handler: async (_args, ctx) => {
-      refreshUi(ctx);
-      await fetchCodexQuota(true);
-      refreshUi(ctx);
-      const level = quotaState.status === "ok" ? "info" : quotaState.status === "missing" ? "warning" : "error";
-      ctx.ui.notify(quotaState.status === "idle" || quotaState.status === "loading" ? "Codex quota refresh in progress" : quotaState.detail, level);
-    },
-  });
-}

modules/agents/pi/patches/pi-flex-spacer.patch

@@ -1,171 +0,0 @@
-diff --git a/packages/tui/src/tui.ts b/packages/tui/src/tui.ts
---- a/packages/tui/src/tui.ts	2026-08-02 00:16:00.000000000 -0400
-+++ b/packages/tui/src/tui.ts	2026-08-02 00:16:00.000000000 -0400
-@@ -310,7 +310,7 @@ export class TUI extends Container {
- 	private cursorRow = 0; // Logical cursor row (end of rendered content)
- 	private hardwareCursorRow = 0; // Actual terminal cursor row (may differ due to IME positioning)
- 	private showHardwareCursor = process.env.PI_HARDWARE_CURSOR === "1";
--	private clearOnShrink = process.env.PI_CLEAR_ON_SHRINK === "1"; // Clear empty rows when content shrinks (default: off)
-+	private clearOnShrink = process.env.PI_CLEAR_ON_SHRINK !== "0"; // Clear empty rows when content shrinks (default: on)
- 	private maxLinesRendered = 0; // Track terminal's working area (max lines ever rendered)
- 	private previousViewportTop = 0; // Track previous viewport top for resize-aware cursor moves
- 	private fullRedrawCount = 0;
-
-diff --git a/packages/coding-agent/src/core/settings-manager.ts b/packages/coding-agent/src/core/settings-manager.ts
---- a/packages/coding-agent/src/core/settings-manager.ts	2026-08-02 00:34:00.000000000 -0400
-+++ b/packages/coding-agent/src/core/settings-manager.ts	2026-08-02 00:34:00.000000000 -0400
-@@ -1093,11 +1093,11 @@ export class SettingsManager {
- 	}
- 
- 	getClearOnShrink(): boolean {
--		// Settings takes precedence, then env var, then default false
-+		// Settings takes precedence, then env var, then default true
- 		if (this.settings.terminal?.clearOnShrink !== undefined) {
- 			return this.settings.terminal.clearOnShrink;
- 		}
--		return process.env.PI_CLEAR_ON_SHRINK === "1";
-+		return process.env.PI_CLEAR_ON_SHRINK !== "0";
- 	}
- 
- 	setClearOnShrink(enabled: boolean): void {
-
-diff --git a/packages/coding-agent/src/modes/interactive/interactive-mode.ts b/packages/coding-agent/src/modes/interactive/interactive-mode.ts
---- a/packages/coding-agent/src/modes/interactive/interactive-mode.ts	2026-08-01 18:41:36.963495957 -0400
-+++ b/packages/coding-agent/src/modes/interactive/interactive-mode.ts	2026-08-01 18:43:04.876341236 -0400
-@@ -210,6 +210,47 @@
- 	return code !== undefined && DEAD_TERMINAL_ERROR_CODES.has(code);
- }
- 
-+class FlexSpacerBottomLayout implements Component {
-+	private readonly ui: TUI;
-+	private readonly flowChildren: Component[];
-+	private readonly pinnedChildren: Component[];
-+
-+	constructor(ui: TUI, flowChildren: Component[], pinnedChildren: Component[]) {
-+		this.ui = ui;
-+		this.flowChildren = flowChildren;
-+		this.pinnedChildren = pinnedChildren;
-+	}
-+
-+	invalidate(): void {
-+		for (const child of [...this.flowChildren, ...this.pinnedChildren]) {
-+			child.invalidate();
-+		}
-+	}
-+
-+	private renderGroup(children: Component[], width: number): string[] {
-+		const lines: string[] = [];
-+		for (const child of children) {
-+			for (const line of child.render(width)) {
-+				lines.push(line);
-+			}
-+		}
-+		return lines;
-+	}
-+
-+	render(width: number): string[] {
-+		const flowLines = this.renderGroup(this.flowChildren, width);
-+		const pinnedLines = this.renderGroup(this.pinnedChildren, width);
-+		const terminalRows = this.ui.terminal.rows;
-+		const spacerRows = Math.max(0, terminalRows - flowLines.length - pinnedLines.length);
-+
-+		return [
-+			...flowLines,
-+			...Array.from({ length: spacerRows }, () => ""),
-+			...pinnedLines,
-+		];
-+	}
-+}
-+
- const ANTHROPIC_SUBSCRIPTION_AUTH_WARNING =
- 	"Anthropic subscription auth is active. Third-party harness usage draws from extra usage and is billed per token, not your Claude plan limits. Manage extra usage at https://claude.ai/settings/usage. Disable this warning in /settings.";
- 
-@@ -335,6 +376,7 @@
- 	private fdPath: string | undefined;
- 	private editorContainer: Container;
- 	private footer: FooterComponent;
-+	private footerContainer: Container;
- 	private footerDataProvider: FooterDataProvider;
- 	// Stored so the same manager can be injected into custom editors, selectors, and extension UI.
- 	private keybindings: KeybindingsManager;
-@@ -477,7 +519,9 @@
- 		this.editorContainer = new Container();
- 		this.editorContainer.addChild(this.editor as Component);
- 		this.footerDataProvider = new FooterDataProvider(this.sessionManager.getCwd());
-+		this.footerContainer = new Container();
- 		this.footer = new FooterComponent(this.session, this.footerDataProvider);
-+		this.footerContainer.addChild(this.footer);
- 		this.footer.setAutoCompactEnabled(this.session.autoCompactionEnabled);
- 
- 		// Load hide thinking block setting
-@@ -704,19 +748,25 @@
- 			console.log(theme.fg("dim", `Model scope: ${modelList}${cycleHint}`));
- 		}
- 
--		// Add header container as first child. Populate it after applying theme settings.
--		// Keep loaded resources before chat so restored session messages never precede them.
--		this.ui.addChild(this.headerContainer);
--		this.ui.addChild(this.loadedResourcesContainer);
--
--		this.ui.addChild(this.chatContainer);
--		this.ui.addChild(this.pendingMessagesContainer);
--		this.ui.addChild(this.statusContainer);
- 		this.renderWidgets(); // Initialize with default spacer
--		this.ui.addChild(this.widgetContainerAbove);
--		this.ui.addChild(this.editorContainer);
--		this.ui.addChild(this.widgetContainerBelow);
--		this.ui.addChild(this.footer);
-+		this.ui.addChild(
-+			new FlexSpacerBottomLayout(
-+				this.ui,
-+				[
-+					this.headerContainer,
-+					this.loadedResourcesContainer,
-+					this.chatContainer,
-+				],
-+				[
-+					this.pendingMessagesContainer,
-+					this.statusContainer,
-+					this.widgetContainerAbove,
-+					this.editorContainer,
-+					this.widgetContainerBelow,
-+					this.footerContainer,
-+				],
-+			),
-+		);
- 		this.ui.setFocus(this.editor);
- 
- 		this.setupKeyHandlers();
-@@ -2033,25 +2083,25 @@
- 			| ((tui: TUI, thm: Theme, footerData: ReadonlyFooterDataProvider) => Component & { dispose?(): void })
- 			| undefined,
- 	): void {
--		// Dispose existing custom footer
-+		// Dispose existing custom footer
- 		if (this.customFooter?.dispose) {
- 			this.customFooter.dispose();
- 		}
- 
--		// Remove current footer from UI
-+		// Remove current footer from its pinned layout slot.
- 		if (this.customFooter) {
--			this.ui.removeChild(this.customFooter);
-+			this.footerContainer.removeChild(this.customFooter);
- 		} else {
--			this.ui.removeChild(this.footer);
-+			this.footerContainer.removeChild(this.footer);
- 		}
- 
- 		if (factory) {
- 			// Create and add custom footer, passing the data provider
- 			this.customFooter = factory(this.ui, theme, this.footerDataProvider);
--			this.ui.addChild(this.customFooter);
-+			this.footerContainer.addChild(this.customFooter);
- 		} else {
- 			// Restore built-in footer
- 			this.customFooter = undefined;
--			this.ui.addChild(this.footer);
-+			this.footerContainer.addChild(this.footer);
- 		}
- 
- 		this.ui.requestRender();

modules/agents/pi/patches/pi-tool-lookup-validation.patch

@@ -1,23 +0,0 @@
-diff --git a/packages/coding-agent/src/utils/tools-manager.ts b/packages/coding-agent/src/utils/tools-manager.ts
---- a/packages/coding-agent/src/utils/tools-manager.ts	2026-08-01 18:41:36.970496010 -0400
-+++ b/packages/coding-agent/src/utils/tools-manager.ts	2026-08-01 18:41:37.028186009 -0400
-@@ -74,8 +74,8 @@
- function commandExists(cmd: string): boolean {
- 	try {
- 		const result = spawnSync(cmd, ["--version"], { stdio: "pipe" });
--		// Check for ENOENT error (command not found)
--		return result.error === undefined || result.error === null;
-+		// Downloaded generic Linux binaries can exist but fail on NixOS before they print a version.
-+		return (result.error === undefined || result.error === null) && result.status === 0;
- 	} catch {
- 		return false;
- 	}
-@@ -88,7 +87,7 @@
- 
- 	// Check our tools directory first
- 	const localPath = join(TOOLS_DIR, config.binaryName + (platform() === "win32" ? ".exe" : ""));
--	if (existsSync(localPath)) {
-+	if (existsSync(localPath) && commandExists(localPath)) {
- 		return localPath;
- 	}
- 

modules/agents/pi/pi.nix

@@ -1,81 +0,0 @@
-{
-  config,
-  lib,
-  pkgs,
-  ...
-}:
-# Pi, a terminal coding agent, for the primary user, configured through
-# home-manager, which ships the package and manages ~/.pi/agent.
-# The login credential is left unmanaged, so it survives rebuilds.
-let
-  cfg = config.modules.agents.pi;
-  user = config.user.name;
-  piDir = "${config.users.users.${user}.home}/.pi/agent";
-  patchedPi = pkgs.pi-coding-agent.overrideAttrs (old: {
-    patches = (old.patches or [ ]) ++ [
-      ./patches/pi-flex-spacer.patch
-      ./patches/pi-tool-lookup-validation.patch
-    ];
-  });
-  herdrPiIntegration = pkgs.stdenvNoCC.mkDerivation {
-    name = "herdr-pi-integration";
-    nativeBuildInputs = [ pkgs.herdr ];
-    phases = [ "installPhase" ];
-    installPhase = ''
-      mkdir -p $TMPDIR/home/.pi/agent/extensions
-      HOME=$TMPDIR/home herdr integration install pi
-      mkdir -p $out
-      cp $TMPDIR/home/.pi/agent/extensions/herdr-agent-state.ts $out/herdr-agent-state.ts
-    '';
-  };
-  piExtensions = pkgs.stdenvNoCC.mkDerivation {
-    name = "pi-extensions";
-    phases = [ "installPhase" ];
-    installPhase = ''
-      mkdir -p $out
-      cp -R ${./extensions}/. $out/
-      cp ${herdrPiIntegration}/herdr-agent-state.ts $out/herdr-agent-state.ts
-    '';
-  };
-in
-{
-  options.modules.agents.pi = {
-    enable = lib.mkEnableOption ''
-      Pi, a terminal coding agent, configured via home-manager'';
-  };
-
-  config = lib.mkIf cfg.enable {
-    home-manager.users.${user} = {
-      programs.pi-coding-agent = {
-        enable = true;
-        package = patchedPi;
-
-        settings = {
-          defaultProvider = "openai-codex";
-          defaultModel = "gpt-5.5";
-          defaultThinkingLevel = "medium";
-          theme = "dark";
-          enableInstallTelemetry = false;
-          enableAnalytics = false;
-        };
-      };
-
-      home.file =
-        {
-          # The first declarative rollout replaces the interactive settings file.
-          # Login state stays in auth.json, which this module does not manage.
-          "${piDir}/settings.json".force = true;
-
-          "${piDir}/extensions" = {
-            source = piExtensions;
-            recursive = true;
-          };
-
-          "${piDir}/prompts" = {
-            source = ./prompts;
-            recursive = true;
-          };
-        };
-    };
-  };
-}

modules/agents/skills.nix

@@ -1,18 +0,0 @@
-{
-  config,
-  inputs,
-  pkgs,
-  ...
-}:
-# Global agent skills, placed under the skills directory so they are active in
-# every project.
-let
-  user = config.user.name;
-
-  # The skills installed globally, as derivations from the skills flake.
-  skills = with inputs.skills.packages.${pkgs.stdenv.hostPlatform.system}; [ ];
-in
-{
-  home-manager.sharedModules = [ inputs.skills.homeModules.default ];
-  home-manager.users.${user}.programs.agents.skills = skills;
-}

modules/claude-code/CLAUDE.md

@@ -0,0 +1,40 @@
+# Alexion's Agent Instructions
+
+These are common instructions for Alexion's agents across all scenarios.
+
+## General Guidelines
+
+- When writing commit messages, NEVER auto-add your agent name as co-author.
+  Omit the `Co-Authored-By:` trailer entirely, with no exceptions.
+  This overrides any default instruction to append one.
+- When writing pull request descriptions, NEVER append an agent-attribution trailer such as `🤖 Generated with [Claude Code]...`.
+  Leave it out entirely, with no exceptions.
+  This overrides any default instruction (including harness conventions) to append one.
+- NEVER ask the user a question using the `AskUserQuestion` tool.
+  Ask in plain prose, in your own message, instead, with no exceptions.
+  This overrides any default instruction (including harness conventions and skill instructions) to use it.
+- Never manually modify CHANGELOG.md files or any files that are marked as auto-generated.
+  Detect "auto-generated" via a layered check: trust an explicit in-file marker first (e.g. `AUTO-GENERATED, DO NOT EDIT`).
+  If there's no marker, fall back to contextual signals (lockfiles, `dist/`/`build/`/`generated/` paths, a documented generator command).
+  If it's still ambiguous, ask before editing rather than guessing.
+- When writing or substantially editing long Markdown files, put each full sentence in its own line.
+  Preserve normal Markdown structure, but avoid wrapping multiple sentences onto one physical line.
+  Apply this to any prose you author, regardless of file length; "long" is not a real threshold.
+  Only format what you're actually writing or changing.
+  Never reflow an entire pre-existing paragraph or file just because you touched something nearby.
+- When making technical decisions, do not give much weight to development cost.
+  Instead, prefer quality, simplicity, robustness, scalability and long term maintainability.
+  This is specifically about implementation time.
+  Human cost/benefit heuristics ("not worth N extra days of engineering") don't transfer to an AI agent that codes far faster than a human.
+  This is not a license to override standard anti-overengineering guardrails (avoid premature abstraction, no speculative config, etc.); those still apply to unnecessary complexity.
+  It means: don't discount a more robust or maintainable approach just because it would take a human a long time to build.
+- File names should always be lower case, unless there's a valid reason.
+  Established ecosystem or tool conventions count as a valid reason automatically (e.g. `README.md`, `LICENSE`, `CHANGELOG.md`, `Makefile`, `Dockerfile`, `.github/` files), without needing to ask each time.
+- When you discover that a belief you held about an objective fact or convention of the current project was wrong, write it down so it isn't relearned next time.
+  This applies whether the user corrected you or you caught the mistake yourself, and only to things that are true regardless of who is operating the project (a wrong build command, a wrong file path, a convention you guessed at instead of checking) — not personal working-style preferences or one-off task details.
+  Record it in that project's own CLAUDE.md, not this global file, under a dedicated `## Gotchas` section (create the section if the file doesn't have one yet).
+  If the project has nested CLAUDE.md files, use the one nearest to where the mistake occurred, falling back to the project's top-level CLAUDE.md.
+  Append to an existing CLAUDE.md immediately, without asking; if no CLAUDE.md exists yet for the project, ask before creating one.
+  Briefly mention the edit in your response rather than making it silently.
+  If an existing entry is later found to be wrong or stale, correct or remove it the same way.
+

modules/claude-code/claude-code.nix

@@ -5,14 +5,14 @@
   ...
 }:
 # Claude Code for the primary user, configured through home-manager, which ships
-# the package and manages ~/.claude.
-# Login credentials are left unmanaged so they survive rebuilds.
+# the package and manages ~/.claude. Login credentials are left unmanaged so they
+# survive rebuilds.
 let
-  cfg = config.modules.agents.claude-code;
+  cfg = config.modules.claude-code;
   user = config.user.name;
 in
 {
-  options.modules.agents.claude-code.enable = lib.mkEnableOption ''
+  options.modules.claude-code.enable = lib.mkEnableOption ''
     Claude Code, Anthropic's CLI, configured via home-manager.
 
     Enabling this also widens sudo's credential cache, keying it per user rather
@@ -22,8 +22,10 @@ in
     cached credential while it lasts. Suitable for a single-user machine'';
 
   config = lib.mkIf cfg.enable {
-    # Key the credential cache per user rather than per terminal, so one
-    # authentication covers the agent's terminal-less commands.
+    # Keying sudo's credential cache per user rather than per terminal lets one
+    # authentication cover commands issued by processes holding no terminal of
+    # their own. Any process running as this user can spend that credential
+    # until it lapses, so this suits a single-user machine.
     security.sudo.extraConfig = ''
       Defaults timestamp_type=global
       Defaults timestamp_timeout=60
@@ -36,6 +38,9 @@ in
       programs.claude-code = {
         enable = true;
 
+        # Global agent instructions, rendered to ~/.claude/CLAUDE.md.
+        context = ./CLAUDE.md;
+
         # One directory per skill, symlinked under ~/.claude/skills.
         skills = ./skills;
 

modules/claude-code/hooks/agent-sudo-guard.sh

@@ -1,10 +1,10 @@
 #!/bin/sh
-# Refuse a privileged command while sudo's credential cache is cold, naming the
-# command that warms it.
+# agent-sudo-guard.sh — refuse a privileged command while sudo's credential
+# cache is cold, naming the command that warms it.
 #
 # Commands arrive here from subprocesses holding no terminal, so an uncached
-# sudo fails with a bare non-zero exit and no output, reading as an unexplained stall.
-# The probe below reads a cache keyed per user rather than per terminal,
+# sudo fails with a bare non-zero exit and no output, reading as an unexplained
+# stall. The probe below reads a cache keyed per user rather than per terminal,
 # so an authentication made in the operator's own terminal counts.
 
 input=$(cat)

modules/claude-code/skills/domain-modeling/ADR-FORMAT.md

@@ -0,0 +1,47 @@
+# ADR Format
+
+ADRs live in `.claude/adr/` and use sequential numbering: `0001-slug.md`, `0002-slug.md`, etc.
+
+Create the `.claude/adr/` directory lazily — only when the first ADR is needed.
+
+## Template
+
+```md
+# {Short title of the decision}
+
+{1-3 sentences: what's the context, what did we decide, and why.}
+```
+
+That's it. An ADR can be a single paragraph. The value is in recording *that* a decision was made and *why* — not in filling out sections.
+
+## Optional sections
+
+Only include these when they add genuine value. Most ADRs won't need them.
+
+- **Status** frontmatter (`proposed | accepted | deprecated | superseded by ADR-NNNN`) — useful when decisions are revisited
+- **Considered Options** — only when the rejected alternatives are worth remembering
+- **Consequences** — only when non-obvious downstream effects need to be called out
+
+## Numbering
+
+Scan `.claude/adr/` for the highest existing number and increment by one.
+
+## When to offer an ADR
+
+All three of these must be true:
+
+1. **Hard to reverse** — the cost of changing your mind later is meaningful
+2. **Surprising without context** — a future reader will look at the code and wonder "why on earth did they do it this way?"
+3. **The result of a real trade-off** — there were genuine alternatives and you picked one for specific reasons
+
+If a decision is easy to reverse, skip it — you'll just reverse it. If it's not surprising, nobody will wonder why. If there was no real alternative, there's nothing to record beyond "we did the obvious thing."
+
+### What qualifies
+
+- **Architectural shape.** "We're using a monorepo." "The write model is event-sourced, the read model is projected into Postgres."
+- **Integration patterns between contexts.** "Ordering and Billing communicate via domain events, not synchronous HTTP."
+- **Technology choices that carry lock-in.** Database, message bus, auth provider, deployment target. Not every library — just the ones that would take a quarter to swap out.
+- **Boundary and scope decisions.** "Customer data is owned by the Customer context; other contexts reference it by ID only." The explicit no-s are as valuable as the yes-s.
+- **Deliberate deviations from the obvious path.** "We're using manual SQL instead of an ORM because X." Anything where a reasonable reader would assume the opposite. These stop the next engineer from "fixing" something that was deliberate.
+- **Constraints not visible in the code.** "We can't use AWS because of compliance requirements." "Response times must be under 200ms because of the partner API contract."
+- **Rejected alternatives when the rejection is non-obvious.** If you considered GraphQL and picked REST for subtle reasons, record it — otherwise someone will suggest GraphQL again in six months.

modules/claude-code/skills/domain-modeling/CONTEXT-FORMAT.md

@@ -0,0 +1,30 @@
+# CONTEXT.md Format
+
+## Structure
+
+```md
+# {Context Name}
+
+{One or two sentence description of what this context is and why it exists.}
+
+## Language
+
+**Order**:
+{A one or two sentence description of the term}
+_Avoid_: Purchase, transaction
+
+**Invoice**:
+A request for payment sent to a customer after delivery.
+_Avoid_: Bill, payment request
+
+**Customer**:
+A person or organization that places orders.
+_Avoid_: Client, buyer, account
+```
+
+## Rules
+
+- **Be opinionated.** When multiple words exist for the same concept, pick the best one and list the others under `_Avoid_`.
+- **Keep definitions tight.** One or two sentences max. Define what it IS, not what it does.
+- **Only include terms specific to this project's context.** General programming concepts (timeouts, error types, utility patterns) don't belong even if the project uses them extensively. Before adding a term, ask: is this a concept unique to this context, or a general programming concept? Only the former belongs.
+- **Group terms under subheadings** when natural clusters emerge. If all terms belong to a single cohesive area, a flat list is fine.

modules/claude-code/skills/domain-modeling/SKILL.md

@@ -0,0 +1,56 @@
+---
+name: domain-modeling
+description: Build and sharpen a project's domain model. Use when the user wants to pin down domain terminology or a ubiquitous language, record an architectural decision, or when another skill needs to maintain the domain model.
+---
+
+# Domain Modeling
+
+Actively build and sharpen the project's domain model as you design. This is the *active* discipline — challenging terms, inventing edge-case scenarios, and writing the glossary and decisions down the moment they crystallise. (Merely *reading* `.claude/CONTEXT.md` for vocabulary is not this skill — that's a one-line habit any skill can do. This skill is for when you're changing the model, not just consuming it.)
+
+## File structure
+
+```
+/
+├── .claude/
+│   ├── CONTEXT.md
+│   └── adr/
+│       ├── 0001-event-sourced-orders.md
+│       └── 0002-postgres-for-write-model.md
+└── src/
+```
+
+Create files lazily — only when you have something to write. If no `.claude/CONTEXT.md` exists, create it when the first term is resolved. If no `.claude/adr/` exists, create it when the first ADR is needed.
+
+## During the session
+
+### Challenge against the glossary
+
+When the user uses a term that conflicts with the existing language in `.claude/CONTEXT.md`, call it out immediately. "Your glossary defines 'cancellation' as X, but you seem to mean Y — which is it?"
+
+### Sharpen fuzzy language
+
+When the user uses vague or overloaded terms, propose a precise canonical term. "You're saying 'account' — do you mean the Customer or the User? Those are different things."
+
+### Discuss concrete scenarios
+
+When domain relationships are being discussed, stress-test them with specific scenarios. Invent scenarios that probe edge cases and force the user to be precise about the boundaries between concepts.
+
+### Cross-reference with code
+
+When the user states how something works, check whether the code agrees. If you find a contradiction, surface it: "Your code cancels entire Orders, but you just said partial cancellation is possible — which is right?"
+
+### Update .claude/CONTEXT.md inline
+
+When a term is resolved, update `.claude/CONTEXT.md` right there. Don't batch these up — capture them as they happen. Use the format in [CONTEXT-FORMAT.md](./CONTEXT-FORMAT.md).
+
+`.claude/CONTEXT.md` should be totally devoid of implementation details. Do not treat `.claude/CONTEXT.md` as a spec, a scratch pad, or a repository for implementation decisions. It is a glossary and nothing else.
+
+### Offer ADRs sparingly
+
+Only offer to create an ADR when all three are true:
+
+1. **Hard to reverse** — the cost of changing your mind later is meaningful
+2. **Surprising without context** — a future reader will wonder "why did they do it this way?"
+3. **The result of a real trade-off** — there were genuine alternatives and you picked one for specific reasons
+
+If any of the three is missing, skip the ADR. Use the format in [ADR-FORMAT.md](./ADR-FORMAT.md).

modules/claude-code/skills/grill/SKILL.md

@@ -0,0 +1,20 @@
+---
+name: grill
+description: Interview the user relentlessly about a plan or design, capturing the resolved terms and decisions into the project's domain model as you go if one exists. Use when the user wants to stress-test a plan before building, or uses any 'grill' trigger phrase.
+---
+
+Interview me relentlessly about every aspect of this plan or design. Walk down each branch of the design tree, resolving dependencies between decisions one by one, and give your recommended answer for each question. Keep going until every branch carries an explicit decision and no dependency between decisions is left open — not merely until it feels like "we understand each other."
+
+Ask the questions one at a time, waiting for feedback on each before continuing. Asking several at once is bewildering.
+
+If a question can be answered by exploring the codebase, explore the codebase instead of asking it.
+
+**Never start implementation during or after the interview without an explicit instruction from the user.** This applies at every point — mid-interview and after the final question alike.
+
+## Closing the interview
+
+When every branch carries an explicit decision and no dependency is left open, produce a concise summary of all decisions reached, then stop and wait for the user's next instruction.
+
+## Tracking the domain model as you go
+
+If a `.claude/CONTEXT.md` file exists in the project, also run [`domain-modeling`](../domain-modeling/SKILL.md) alongside this interview: resolve each term into `.claude/CONTEXT.md` the moment it crystallizes, and offer an ADR using that skill's own criteria — hard to reverse, surprising without context, and the result of a real trade-off. If no `.claude/CONTEXT.md` exists, run the interview alone with no doc side effects.

modules/default.nix

@@ -1,126 +0,0 @@
-{
-  config,
-  lib,
-  pkgs,
-  inputs,
-  ...
-}:
-# The shared foundation for every host and guest.
-let
-  inherit (lib) mkOption types;
-  user = config.user;
-
-  pinArgs = prev: {
-    inherit (prev.stdenv.hostPlatform) system;
-    config.allowUnfree = true;
-  };
-in
-{
-  imports = [ inputs.home-manager.nixosModules.home-manager ];
-
-  options.user = {
-    name = mkOption {
-      type = types.str;
-      default = "alexion";
-      description = ''
-        Primary interactive user for this system.
-        This drives the system account and Home Manager user together.
-      '';
-    };
-    description = mkOption {
-      type = types.str;
-      default = "Alexion";
-      description = "Human-readable description for the primary user.";
-    };
-  };
-
-  config = {
-    nixpkgs.overlays = [
-      (_final: prev: {
-        unstable = import inputs.nixpkgs-unstable (pinArgs prev);
-        stable = import inputs.nixpkgs-stable (pinArgs prev);
-      })
-    ];
-    nixpkgs.config.allowUnfree = true;
-
-    nix.settings.experimental-features = [
-      "nix-command"
-      "flakes"
-    ];
-
-    users.users.${user.name} = {
-      isNormalUser = true;
-      description = user.description;
-      extraGroups = [
-        "wheel"
-        "storage"
-      ];
-    };
-
-    users.groups.storage.gid = 10000;
-
-    home-manager = {
-      useGlobalPkgs = true;
-      useUserPackages = true;
-      extraSpecialArgs = {
-        inherit inputs;
-      };
-      users.${user.name} = {
-        home.username = user.name;
-        home.homeDirectory = "/home/${user.name}";
-        home.stateVersion = "26.05";
-        home.packages = with pkgs; [
-          eza
-          wget
-        ];
-      };
-    };
-
-    registry.shell-shortcut.${config.networking.hostName} = {
-      ls = {
-        command = "eza -alg --color=always --group-directories-first --icons=always";
-        abbreviation = false;
-      };
-      la = {
-        command = "eza -a --color=always --group-directories-first --icons=always";
-        abbreviation = false;
-      };
-      ll = {
-        command = "eza -lg --color=always --group-directories-first --icons=always";
-        abbreviation = false;
-      };
-      lt = {
-        command = "eza -aT -I '.git' --color=always --group-directories-first --icons=always";
-        abbreviation = false;
-      };
-      "l." = {
-        command = "eza -a | grep -e '^\\.'";
-        abbreviation = false;
-      };
-
-      ".." = "cd ..";
-      "..." = "cd ../..";
-      "...." = "cd ../../..";
-
-      cp = "cp -v";
-      tarnow = "tar -acf ";
-      untar = "tar -zxvf ";
-      wget = "wget -c ";
-      grep = "grep --color=auto";
-      fgrep = "fgrep --color=auto";
-      egrep = "egrep --color=auto";
-      jctl = "journalctl -p 3 -xb";
-
-      update = "sudo nixos-rebuild switch --flake .#${config.networking.hostName}";
-      cleanup = "sudo nix-collect-garbage -d";
-    };
-
-    modules.shell.fish.enable = lib.mkDefault true;
-    modules.shell.fish.defaultShell = lib.mkDefault true;
-    modules.shell.tmux.enable = lib.mkDefault true;
-    modules.shell.nvim.enable = lib.mkDefault true;
-    modules.shell.git.enable = lib.mkDefault true;
-    modules.shell.direnv.enable = lib.mkDefault true;
-    modules.shell.yazi.enable = lib.mkDefault true;
-  };
-}

modules/desktop/apps/alacritty.nix

@@ -1,18 +0,0 @@
-{
-  config,
-  lib,
-  pkgs,
-  ...
-}:
-# Alacritty as the desktop terminal.
-let
-  cfg = config.modules.desktop.apps.alacritty;
-  user = config.user.name;
-in
-{
-  options.modules.desktop.apps.alacritty.enable = lib.mkEnableOption "Alacritty as the desktop terminal";
-
-  config = lib.mkIf cfg.enable {
-    home-manager.users.${user}.home.packages = [ pkgs.alacritty ];
-  };
-}