Rewrite codex-maintenance.sh to scope CI checks to changed files

CI was running a full eval of every host + package on every push/PR,
which was slow enough to routinely time out the Gitea runner. Default
mode now diffs against a base ref and scopes nixpkgs-fmt/statix/eval to
the files that changed and the hosts/packages they can affect; a change
to flake.nix/flake.lock/variables.nix/modules/common/* (or any other
modules/*.nix outside platforms//build-types, whose blast radius isn't
inferable from the path) falls back to evaluating everything. The old
full sweep moves behind --full-check, which CI never passes; --dry-run
adds build-planning on top of whichever scope is active.

Also trims codex-setup.sh's redundant full host eval loop -- that's
what codex-maintenance.sh is for; setup should just install tooling.

.gitea/workflows/check-nixos.yml

@@ -13,9 +13,17 @@ jobs:
     steps:
       - name: Check out repository
         uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
 
       - name: Install Nix
         uses: DeterminateSystems/nix-installer-action@v19
 
-      - name: Run maintenance checks (secrets, fmt, lint, eval)
+      # Scoped to files changed since the PR base / previous push -- see
+      # scripts/codex-maintenance.sh. CI never passes --full-check: that
+      # full sweep is for local/manual use, since it's slow enough to time
+      # out this runner.
+      - name: Run maintenance checks (secrets, fmt, lint, eval -- changed files only)
+        env:
+          MAINT_BASE_SHA: ${{ github.event.pull_request.base.sha || github.event.before }}
         run: bash scripts/codex-maintenance.sh

.github/workflows/check-nixos.yml

@@ -13,9 +13,17 @@ jobs:
     steps:
       - name: Check out repository
         uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
 
       - name: Install Nix
         uses: DeterminateSystems/nix-installer-action@v19
 
-      - name: Run maintenance checks (secrets, fmt, lint, eval)
+      # Scoped to files changed since the PR base / previous push -- see
+      # scripts/codex-maintenance.sh. CI never passes --full-check: that
+      # full sweep is for local/manual use, since it's slow enough to time
+      # out this runner.
+      - name: Run maintenance checks (secrets, fmt, lint, eval -- changed files only)
+        env:
+          MAINT_BASE_SHA: ${{ github.event.pull_request.base.sha || github.event.before }}
         run: bash scripts/codex-maintenance.sh

AGENTS.md

@@ -35,9 +35,14 @@ Use these commands when validating changes:
 ```bash
 bash scripts/codex-setup.sh
 bash scripts/codex-maintenance.sh
-bash scripts/codex-maintenance.sh dry-run
 ```
 
+With no flags, `codex-maintenance.sh` scopes fmt-check/statix/eval to files
+changed against a base ref — this is what CI runs on every push/PR. For the
+full sweep (every host, every package — slow; CI never runs this), use
+`bash scripts/codex-maintenance.sh --full-check` (add `--dry-run` for build
+planning on top of whichever scope is active).
+
 Host evaluation is safe when limited to drvPath checks:
 
 ```bash

CLAUDE.md

@@ -37,11 +37,22 @@ machines when deployed.
 # One-time environment bootstrap (installs Nix if missing, prints hosts)
 bash scripts/codex-setup.sh
 
-# Full validation: secret grep, nixpkgs-fmt --check, statix lint, eval all hosts
+# Changed-files-only validation: secret grep (whole repo), nixpkgs-fmt --check
+# and statix on changed *.nix files, eval of the hosts/packages those changes
+# can affect. This is what CI runs on every push/PR.
 bash scripts/codex-maintenance.sh
 
-# Same, plus a dry-run build (no result symlink) of every host's toplevel
+# Full sweep: nixpkgs-fmt --check/statix over the whole tree, eval every host
-bash scripts/codex-maintenance.sh dry-run
+# and package. Slow (minutes) -- CI never runs this; use it locally before a
+# release or after touching modules/common/*, flake.nix, or variables.nix for
+# extra confidence beyond the automatic full-fallback those paths already
+# trigger in the default mode (see below).
+bash scripts/codex-maintenance.sh --full-check
+
+# Either mode, plus a dry-run build (no result symlink) of every host/package
+# in whichever scope is active
+bash scripts/codex-maintenance.sh --dry-run
+bash scripts/codex-maintenance.sh --full-check --dry-run
 
 # List the hosts the flake currently exposes
 nix eval --json .#nixosConfigurations --apply builtins.attrNames | jq -r '.[]'
@@ -58,36 +69,80 @@ maintenance script pulls them via `nix run github:NixOS/nixpkgs/nixos-25.11#<too
 There is no test suite — "correctness" here means the flake evaluates and
 `nixpkgs-fmt`/`statix` are clean.
 
-**In an interactive agent session**, prefer targeted checks over full-repo
+With no flags, `codex-maintenance.sh` diffs against a base ref (env
-sweeps: after editing one or two hosts/modules, evaluate just the
+`MAINT_BASE_SHA`, else the PR base SHA in CI, else `HEAD^` locally) and scopes
-`nixosConfigurations.<host>` you touched (plus any `config.system.build.tarball`
+fmt-check/statix to the changed `*.nix` files and eval to the hosts/packages
-/`diskoImagesScript`/package output affected) rather than looping over every
+those changes can affect — a `hosts/<name>/host.nix` edit only evals that
-host — `codex-maintenance.sh` evaluates every `nixosConfigurations` host plus
+host's targets, a `modules/platforms/<platform>.nix` edit only evals that
-every package/tarball/image variant and is slow to run after each small
+platform's hosts, and so on. A change to `flake.nix`, `flake.lock`,
-change. Reserve a full
+`variables.nix`, `modules/common/*`, or any other `modules/*.nix` file outside
-`codex-maintenance.sh` run for changes that plausibly affect every host
+`platforms/`/`build-types/` (whose blast radius isn't safely inferable from
-(`modules/common/*`, `flake.nix`, `variables.nix`) or as a final check before
+the path alone) falls back to evaluating every host and package, same as
-committing. This is a session-workflow preference only — it does not apply to
+`--full-check` would, just without the whole-tree fmt/statix sweep. This
-CI, which should keep running the full script on every push/PR regardless of
+exists because the whole-tree sweep is what was timing out CI; **CI always
-diff size; that's the point of it.
+runs the plain, no-flag form and never passes `--full-check`.**
+
+The default mode's diff is against the working tree (uncommitted and staged
+edits included, not just committed ones), so it's already the right tool for
+an interactive session too: after editing one or two hosts/modules, plain
+`bash scripts/codex-maintenance.sh` naturally scopes to just what you
+touched. Reserve `--full-check` for changes that plausibly affect every host
+(`modules/common/*`, `flake.nix`, `variables.nix` — though the default mode
+already falls back to evaluating everything for those paths, `--full-check`
+additionally re-checks fmt/statix over the whole tree) or as a final check
+before committing.
 
 ## Scripts
 
-Beyond `codex-setup.sh`/`codex-maintenance.sh` above, `scripts/` also has:
+Beyond `codex-setup.sh`/`codex-maintenance.sh` above, `scripts/` is
+organized by purpose: `scripts/secrets/` (sops/age + SSH host-key
+management), `scripts/proxmox/` (Proxmox deployment), `scripts/lib/`
+(shared helpers, sourced by the scripts below — not run directly), and a
+handful of repo-wide scripts left at the top level (`env.sh`,
+`bump-nixpkgs-release.sh`, plus `codex-setup.sh`/`codex-maintenance.sh`
+above). When adding a new script, put it in the matching subfolder rather
+than the top level, and if it duplicates logic another script already has,
+lift the shared part into `scripts/lib/` instead of copying it.
 
-- `scripts/sync-host-keys.sh` — generates/registers SSH host keys and their
+### `scripts/secrets/`
-  `.sops.yaml`/`secrets/*.yaml` recipients for flake targets, idempotently
+
-  (`--all`, `<target>`, `--remove`, `--regenerate-all-keys`, all with
+- `scripts/secrets/sync-host-keys.sh` — generates/registers SSH host keys
-  `--dry-run`). The primary tool for provisioning a new host's secrets
+  and their `.sops.yaml`/`secrets/*.yaml` recipients for flake targets,
-  access — see "Creating a new machine" in `docs/auto-installer.md`.
+  idempotently (`--all`, `<target>`, `--remove`, `--regenerate-all-keys`,
-- `scripts/prepare-host-key.sh` — narrower predecessor: generates a key by
+  all with `--dry-run`). The primary tool for provisioning a new host's
-  an arbitrary name without touching `.sops.yaml`. Still useful to
+  secrets access — see "Creating a new machine" in `docs/auto-installer.md`.
+- `scripts/secrets/prepare-host-key.sh` — narrower predecessor: generates a
+  key by an arbitrary name without touching `.sops.yaml`. Still useful to
   pre-generate a key before its flake target exists yet, since
   `sync-host-keys.sh` can only act on targets `nixosConfigurations` already
   has.
-- `scripts/create-proxmox-resource.sh` — builds a `lxc-*`/`proxmox-*`
+- `scripts/secrets/rotate-admin-key.sh <backup-admin-key> [--new-key-file
-  target's tarball/disk image and creates it on a real Proxmox node
+  <path>] [--dry-run]` — rotates `.sops.yaml`'s `&admin` age key: decrypts
-  (`pct create` against the tarball as a CT template / `qm create`+
+  with a backed-up copy of the key currently trusted as `&admin` (verified
+  by deriving its public key and comparing, not taken on faith), replaces
+  the `&admin` line with a new key already present in the environment
+  (defaults to wherever sops/age itself would look), and runs
+  `sops updatekeys` on every `secrets/*.yaml`. One-way: the old key can no
+  longer decrypt anything re-encrypted this way. This is the automation
+  for the manual steps `sync-host-keys.sh`/`create-proxmox-resource.sh`
+  print when they bootstrap a brand-new, not-yet-trusted key on a machine
+  with no prior admin access.
+- `scripts/secrets/backup-admin-key.sh <dest-path> [--key-file <path>]
+  [--force] [--dry-run]` — copies the local sops age key (source
+  resolution matches sops/age itself: `$SOPS_AGE_KEY` inline, then
+  `--key-file`, then `$SOPS_AGE_KEY_FILE`, then the XDG default) to an
+  arbitrary destination path with `0600` permissions, validating it's a
+  real age identity and round-tripping the public key before and after the
+  write. Refuses to overwrite an existing `<dest-path>` without `--force`.
+  Purely a local filesystem copy — never touches `.sops.yaml`/
+  `secrets/*.yaml` or the repo at all. The resulting file is exactly what
+  `rotate-admin-key.sh` expects as its backup-key argument.
+
+### `scripts/proxmox/`
+
+- `scripts/proxmox/create-proxmox-resource.sh` — builds a `lxc-*`/
+  `proxmox-*` target's tarball/disk image and creates it on a real Proxmox
+  node (`pct create` against the tarball as a CT template / `qm create`+
   `importdisk`), or reconfigures an existing resource's cores/memory/disk
   size (`--modify`, always requires typing the VMID back to confirm).
   Checks for an already-uploaded image on the node before building
@@ -99,15 +154,12 @@ Beyond `codex-setup.sh`/`codex-maintenance.sh` above, `scripts/` also has:
   unless `--allow-duplicate-host` is passed. `--dry-run` throughout both
   modes. The first time it has to bootstrap build tooling on a node (i.e.
   `nix` wasn't already on its `PATH`), it also runs
-  `scripts/configure-nix-cache-client.sh` there (non-fatally — a failure
+  `scripts/proxmox/configure-nix-cache-client.sh` there (non-fatally — a
-  just falls back to building from source / `cache.nixos.org`) so the
+  failure just falls back to building from source / `cache.nixos.org`) so
-  node substitutes from and can offload builds to nix-cache on every
+  the node substitutes from and can offload builds to nix-cache on every
   subsequent run, not just this one.
-- `scripts/env.sh` — shared config (`PROXMOX_HOST`, storage pool, bridge,
+- `scripts/proxmox/configure-nix-cache-client.sh [--dry-run]
-  default cores/memory) sourced by `create-proxmox-resource.sh`. Add new
+  [--no-remote-builder] [--no-restart]` — the non-NixOS equivalent of
-  cross-script config here instead of duplicating it per-script.
-- `scripts/configure-nix-cache-client.sh [--dry-run] [--no-remote-builder]
-  [--no-restart]` — the non-NixOS equivalent of
   `modules/nix-cache/client.nix`/`remote-builder-client.nix`, for a plain
   Debian machine with the Nix package manager (not NixOS) already
   installed: run as root *on that machine* to add nix-cache as a
@@ -120,32 +172,39 @@ Beyond `codex-setup.sh`/`codex-maintenance.sh` above, `scripts/` also has:
   `/etc/ssh/ssh_known_hosts`. Idempotent (re-running replaces its own
   marked block rather than duplicating it); restarts `nix-daemon` by
   default so the change takes effect immediately.
+
+### `scripts/lib/`
+
+Sourced by the scripts above, never run directly:
+
+- `nix-bootstrap.sh` — `NIX_CONFIG`/`ensure_nix_profile`, shared by
+  `codex-setup.sh`/`codex-maintenance.sh` and the remote build commands
+  `create-proxmox-resource.sh` runs over SSH.
+- `nix-eval.sh` — `NIX_EVAL_FLAGS` plus `list_flake_targets`/
+  `flake_target_hostname` flake-introspection helpers.
+- `ssh-host-keys.sh` — `generate_host_ed25519_key`/`ssh_pubkey_to_age`,
+  shared by `sync-host-keys.sh` and `prepare-host-key.sh`.
+- `sops-age.sh` — `age_pubkey_from_identity_file`/`sops_yaml_admin_pubkey`/
+  `sops_updatekeys` plus the shared sops/age default key-file resolution,
+  shared by `backup-admin-key.sh`, `rotate-admin-key.sh`, and
+  `sync-host-keys.sh`.
+- `confirm.sh` — `confirm_typed`, the "type X back to confirm" destructive-
+  action prompt shared by `create-proxmox-resource.sh` and
+  `sync-host-keys.sh`.
+- `sync-host-keys-edit-sops.py` — the `.sops.yaml` anchor/key_groups editor
+  `sync-host-keys.sh` shells out to (see that script for why: precise,
+  idempotent YAML edits are impractical in bash).
+
+### Top level
+
+- `scripts/env.sh` — shared config (`PROXMOX_HOST`, storage pool, bridge,
+  default cores/memory) sourced by `create-proxmox-resource.sh`. Add new
+  cross-script config here instead of duplicating it per-script.
 - `scripts/bump-nixpkgs-release.sh` — bumps `flake.nix`'s `nixpkgs.url`/
   `home-manager.url` in place. Exists because flake input URLs can't
   reference `variables.nix` (confirmed empirically — `nix flake metadata`
   errors on it), so this is the closest equivalent to a single source of
   truth for the tracked release.
-- `scripts/rotate-admin-key.sh <backup-admin-key> [--new-key-file <path>]
-  [--dry-run]` — rotates `.sops.yaml`'s `&admin` age key: decrypts with a
-  backed-up copy of the key currently trusted as `&admin` (verified by
-  deriving its public key and comparing, not taken on faith), replaces the
-  `&admin` line with a new key already present in the environment
-  (defaults to wherever sops/age itself would look), and runs
-  `sops updatekeys` on every `secrets/*.yaml`. One-way: the old key can no
-  longer decrypt anything re-encrypted this way. This is the automation
-  for the manual steps `sync-host-keys.sh`/`create-proxmox-resource.sh`
-  print when they bootstrap a brand-new, not-yet-trusted key on a machine
-  with no prior admin access.
-- `scripts/backup-admin-key.sh <dest-path> [--key-file <path>] [--force]
-  [--dry-run]` — copies the local sops age key (source resolution matches
-  sops/age itself: `$SOPS_AGE_KEY` inline, then `--key-file`, then
-  `$SOPS_AGE_KEY_FILE`, then the XDG default) to an arbitrary destination
-  path with `0600` permissions, validating it's a real age identity and
-  round-tripping the public key before and after the write. Refuses to
-  overwrite an existing `<dest-path>` without `--force`. Purely a local
-  filesystem copy — never touches `.sops.yaml`/`secrets/*.yaml` or the
-  repo at all. The resulting file is exactly what `rotate-admin-key.sh`
-  expects as its backup-key argument.
 
 `sync-host-keys.sh`, `create-proxmox-resource.sh`, and
 `rotate-admin-key.sh` genuinely mutate real state when run for real (not

README.md

@@ -34,7 +34,7 @@ anywhere in this repo — that's live infrastructure state, not something a
 committed file can keep accurate, and it changes independently of the code.
 Check the Proxmox node itself, or `/etc/flake-target` on a running host (see
 below), if you need to know what's really out there right now.
-`scripts/create-proxmox-resource.sh`'s duplicate-host guard works the same
+`scripts/proxmox/create-proxmox-resource.sh`'s duplicate-host guard works the same
 way: it checks the Proxmox node directly rather than any file here.
 
 Each buildtype's `hosts/<name>/host.nix` carries the per-machine identity
@@ -74,10 +74,19 @@ Safe validation commands for Codex and local review:
 
 ```bash
 bash scripts/codex-setup.sh
-bash scripts/codex-maintenance.sh dry-run
 bash scripts/codex-maintenance.sh
 ```
 
+`codex-maintenance.sh` with no flags (what CI runs on every push/PR) scopes
+fmt-check/statix/eval to files changed against a base ref — fast, but only
+as thorough as the diff. For the full sweep (every host, every package,
+fmt-check and statix over the whole tree — slow, CI never runs this):
+
+```bash
+bash scripts/codex-maintenance.sh --full-check
+bash scripts/codex-maintenance.sh --full-check --dry-run
+```
+
 For individual host evaluation:
 
 ```bash
@@ -114,7 +123,7 @@ Three different paths depending on target, none of them involving a manual
   disk image and attached to a new VM with no install step — see
   `docs/proxmox-images.md`.
 
-`scripts/create-proxmox-resource.sh --type lxc|vm --host <name>` automates
+`scripts/proxmox/create-proxmox-resource.sh --type lxc|vm --host <name>` automates
 either of the last two end to end (host-key registration, building the
 image directly on the Proxmox node itself, `pct create`/`qm create`), with
 `--dry-run` and a guard against duplicating an already-deployed host's

docs/auto-installer.md

@@ -73,7 +73,7 @@ booting one:
 
 First boot runs `boot.postBootCommands` (registers the Nix store DB and
 system profile) — there's no separate activation step to run yourself.
-`scripts/create-proxmox-resource.sh --type lxc --host <name>` automates all
+`scripts/proxmox/create-proxmox-resource.sh --type lxc --host <name>` automates all
 of this (host-key handling, building the tarball directly on the Proxmox
 node itself, `pct create` with the flags above) — see its `--help`.
 
@@ -102,7 +102,7 @@ groups required, got 0`, and *every* secret (including this host's own
 login) permanently fails to decrypt, silently — no error in the boot log
 at all, since the activation step that would install secrets only runs on
 a from-scratch first activation and skips silently once `/run/current-system`
-already exists. `scripts/create-proxmox-resource.sh` always builds with
+already exists. `scripts/proxmox/create-proxmox-resource.sh` always builds with
 `NIXOS_HOST_KEYS_DIR` set for this reason.
 
 ## Layout
@@ -116,10 +116,10 @@ already exists. `scripts/create-proxmox-resource.sh` always builds with
   `docs/pxe-boot.md`).
 - `modules/installer/host-keys.nix` — optionally bakes pre-generated SSH
   host keys into the image; see "Host keys" below.
-- `scripts/sync-host-keys.sh` — admin-workstation tool that generates,
+- `scripts/secrets/sync-host-keys.sh` — admin-workstation tool that generates,
   registers, and (via `--remove`/`--regenerate-all-keys`) retires host
   keys; see "Creating a New Machine" below.
-- `scripts/prepare-host-key.sh` — narrower predecessor: generates a single
+- `scripts/secrets/prepare-host-key.sh` — narrower predecessor: generates a single
   key by an arbitrary name without touching `.sops.yaml`. Still useful for
   pre-generating a key *before* its flake target exists (`sync-host-keys.sh`
   can only act on targets `nixosConfigurations` already has); otherwise
@@ -238,7 +238,7 @@ GitHub token behind sops-nix for all of them).
 2. **On your admin workstation, generate and register its host key:**
 
    ```sh
-   ./scripts/sync-host-keys.sh <flake-target>
+   ./scripts/secrets/sync-host-keys.sh <flake-target>
    ```
 
    This generates `host-keys/<flake-target>_ssh_host_ed25519_key(.pub)`,
@@ -250,7 +250,7 @@ GitHub token behind sops-nix for all of them).
 
    Doing this for every host that needs one at once — after adding several
    new targets, or just to catch up any that were missed — is
-   `./scripts/sync-host-keys.sh --all`. See `scripts/sync-host-keys.sh --help`
+   `./scripts/secrets/sync-host-keys.sh --all`. See `scripts/secrets/sync-host-keys.sh --help`
    for its other modes (`--remove`, `--regenerate-all-keys`).
 
 3. **Commit and push.** The flake build the installer uses has to see the

docs/flake-lock-automation.md

@@ -8,9 +8,14 @@ and to verify that declared NixOS hosts still evaluate after dependency updates.
 - A scheduled workflow runs `nix flake update` once per week.
 - On GitHub, any resulting `flake.lock` change is proposed through a pull request.
 - On Gitea, the workflow can commit and push `flake.lock` directly when PR automation is not configured.
-- A separate CI workflow evaluates every configured host before merge, listed
+- A separate CI workflow runs `scripts/codex-maintenance.sh` before merge.
-  dynamically via `nix eval --json .#nixosConfigurations --apply builtins.attrNames`
+  Its default mode scopes eval to the hosts/packages a change can affect,
-  rather than hand-enumerated, so it can't drift as `<platform>-<buildtype>`
+  determined from a git diff against the PR base — but a `flake.lock` change
+  is treated as repo-wide and always falls back to evaluating every host, so
+  a lock-file update PR still gets full coverage. Hosts are still listed
+  dynamically via
+  `nix eval --json .#nixosConfigurations --apply builtins.attrNames` rather
+  than hand-enumerated, so that fallback can't drift as `<platform>-<buildtype>`
   targets are added or removed. See `README.md` for the current target list.
 
 ## Why hosts should stop using `--upgrade-all`

docs/proxmox-images.md

@@ -7,7 +7,7 @@ config (`modules/disko/proxmox.nix`) already used to format a real disk on
 install, so there's nothing host-specific to write; it's available for every
 `proxmox-*` target automatically.
 
-`scripts/create-proxmox-resource.sh --type vm --host <name>` automates the
+`scripts/proxmox/create-proxmox-resource.sh --type vm --host <name>` automates the
 whole walkthrough below (and the equivalent LXC one) end to end, including
 host-key handling and building the image directly on the Proxmox node
 itself (no local build, no image transfer) — see its `--help`. The steps
@@ -51,7 +51,7 @@ sudo ./result \
   --build-memory 2048
 ```
 
-Generate the key first with `scripts/sync-host-keys.sh <hostname>`, same
+Generate the key first with `scripts/secrets/sync-host-keys.sh <hostname>`, same
 as any other host — see `docs/auto-installer.md` for the full walkthrough
 (it registers the new key in `.sops.yaml` and re-encrypts the affected
 `secrets/*.yaml` files too, no manual editing needed).

modules/installer/common.nix

@@ -130,7 +130,7 @@
         # at *activation* time, which runs before systemd would otherwise
         # generate one on first boot. Without pre-seeding it here, secrets
         # (including the login password) fail to decrypt on first boot.
-        # Generate the key with scripts/prepare-host-key.sh first.
+        # Generate the key with scripts/secrets/prepare-host-key.sh first.
         #
         # Two places a key can come from, checked in order:
         #   /etc/host-keys  — baked into this image at build time (see
@@ -150,7 +150,7 @@
         else
             echo "WARNING: no SSH host key found for ''${choice} (checked /etc/host-keys and /root/host-keys)"
             echo "sops-nix secrets (including the login password) will NOT decrypt on first boot."
-            echo "Run scripts/prepare-host-key.sh for host ''${choice} on your admin workstation first,"
+            echo "Run scripts/secrets/prepare-host-key.sh for host ''${choice} on your admin workstation first,"
             echo "then either rebuild this image with NIXOS_HOST_KEYS_DIR set, or scp the result to"
             echo "/root/host-keys/ on this machine."
             read -rp "Continue without a pre-seeded key anyway? (y/N): " skip_key

modules/platforms/lxc.nix

@@ -14,7 +14,7 @@ let
   # Without this, config.system.build.tarball's built-in system just
   # generates a fresh host key at first boot like any other host would --
   # but sops-nix derives its decryption key from *this* file, and
-  # .sops.yaml only trusts whatever key scripts/sync-host-keys.sh already
+  # .sops.yaml only trusts whatever key scripts/secrets/sync-host-keys.sh already
   # registered for this exact target name. A freshly-generated key can
   # never match that, so every secret (including this host's own login)
   # permanently fails to decrypt. Confirmed live: sops-install-secrets
@@ -26,7 +26,7 @@ let
   hostKeysDir = /. + hostKeysDirStr;
 
   # flakeTarget ("${platform}-${buildType}") comes in via specialArgs from
-  # flake.nix's mkTarget -- exactly the name scripts/sync-host-keys.sh
+  # flake.nix's mkTarget -- exactly the name scripts/secrets/sync-host-keys.sh
   # registers keys under. Deliberately not read back from
   # config.environment.etc."flake-target" (which is set to the same value)
   # -- this module also *contributes* to environment.etc below, and a

scripts/bump-nixpkgs-release.sh

@@ -129,5 +129,6 @@ echo "flake.lock still points at the old input revisions until refreshed. Either
 echo "  nix flake update nixpkgs home-manager   # just these two inputs"
 echo "  nix flake update                        # everything — see docs/flake-lock-automation.md"
 echo
-echo "Then run 'bash scripts/codex-maintenance.sh dry-run' before committing —"
+echo "Then run 'bash scripts/codex-maintenance.sh --full-check --dry-run' before"
-echo "a channel bump can shift option defaults across every host."
+echo "committing — a channel bump can shift option defaults across every host,"
+echo "and only --dry-run actually builds anything to catch that."

scripts/codex-maintenance.sh

@@ -1,4 +1,21 @@
 #!/usr/bin/env bash
+# Validation entry point for CI and local/agent review.
+#
+# Default mode (what CI runs on every push/PR): fmt-check, statix, and eval
+# are scoped to files that actually changed against a base ref, plus
+# whichever hosts/packages those changes can affect. This exists because
+# the unscoped sweep below is slow enough to time out CI runners -- see
+# --full-check.
+#
+# --full-check: the historical full sweep (every host, every package,
+# fmt --check ./statix check . over the whole tree). Slow -- minutes, not
+# seconds. CI never passes this; run it locally before a release or after
+# touching modules/common/*, flake.nix, or variables.nix if you want extra
+# confidence beyond what the changed-files scope already covers for those
+# paths (see below).
+#
+# --dry-run: adds `nix build --dry-run --no-link` for whatever scope is
+# active (changed-files scope by default, full scope under --full-check).
 set -euo pipefail
 
 script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
@@ -7,7 +24,39 @@ source "${script_dir}/lib/nix-bootstrap.sh"
 # shellcheck source=lib/nix-eval.sh
 source "${script_dir}/lib/nix-eval.sh"
 
-MODE="${1:-validate}"
+repo_root="$(cd "${script_dir}/.." && pwd)"
+cd "$repo_root"
+
+full_check=false
+dry_run=false
+
+usage() {
+  cat <<'EOF'
+Usage: scripts/codex-maintenance.sh [--full-check] [--dry-run]
+
+  --full-check  Run the full sweep: fmt-check and statix over the whole
+                repo, eval every host and package. Slow. Never run by CI.
+  --dry-run     Additionally run `nix build --dry-run --no-link` for
+                whatever scope is active.
+
+With neither flag (the CI default), fmt-check/statix/eval are scoped to
+files changed against a base ref (env MAINT_BASE_SHA, else the PR base,
+else HEAD^), plus the hosts/packages those changes can affect.
+EOF
+}
+
+for arg in "$@"; do
+  case "$arg" in
+    --full-check) full_check=true ;;
+    --dry-run) dry_run=true ;;
+    -h|--help) usage; exit 0 ;;
+    *)
+      echo "Unknown argument: $arg" >&2
+      usage >&2
+      exit 1
+      ;;
+  esac
+done
 
 ensure_nix_profile
 
@@ -16,12 +65,6 @@ if ! command -v nix >/dev/null 2>&1; then
   exit 127
 fi
 
-hosts="$(list_flake_targets .)"
-
-echo "Hosts:"
-echo "$hosts"
-
-echo
 echo "Checking for obvious committed secrets..."
 if grep -RInE 'github_pat_|ghp_|access-tokens|hashedPassword[[:space:]]*=' \
   --exclude-dir=.git \
@@ -33,49 +76,200 @@ else
   echo "No obvious token patterns found."
 fi
 
+mapfile -t all_hosts < <(list_flake_targets .)
+mapfile -t all_packages < <(nix eval --json "${NIX_EVAL_FLAGS[@]}" .#packages.x86_64-linux --apply builtins.attrNames | jq -r '.[]')
+
+# host_targets_for_dir <hosts-subdir-name>
+# Prints the nixosConfigurations target names whose hostPath is
+# ./hosts/<dir>/host.nix, derived straight from flake.nix's generatedTargets
+# (one mkTarget { ... } call per line) rather than a hand-maintained table,
+# so it can't drift the way a copied mapping would.
+host_targets_for_dir() {
+  local dir="$1"
+  grep -oE '^[[:space:]]*[A-Za-z0-9_-]+ = mkTarget \{[^}]*hostPath = \./hosts/'"${dir}"'/host\.nix;[^}]*\};' flake.nix \
+    | sed -E 's/^[[:space:]]*([A-Za-z0-9_-]+) = mkTarget.*/\1/' \
+    || true
+}
+
+declare -a changed_files=()
+scope_desc="full repo"
+
+if ! $full_check; then
+  resolve_base_ref() {
+    if [[ -n "${MAINT_BASE_SHA:-}" ]] && git cat-file -e "${MAINT_BASE_SHA}^{commit}" 2>/dev/null; then
+      echo "$MAINT_BASE_SHA"
+      return
+    fi
+    if git rev-parse --verify -q HEAD^ >/dev/null 2>&1; then
+      echo "HEAD^"
+      return
+    fi
+    git hash-object -t tree /dev/null
+  }
+
+  base_ref="$(resolve_base_ref)"
+  echo
+  echo "Changed-files scope: diffing against ${base_ref}"
+  mapfile -t changed_files < <(git diff --name-only --diff-filter=ACMR "$base_ref" -- . | sort -u)
+
+  if [[ ${#changed_files[@]} -eq 0 ]]; then
+    echo "No changed files detected."
+  else
+    printf '  %s\n' "${changed_files[@]}"
+  fi
+  scope_desc="changed files only (base: ${base_ref})"
+fi
+
+# Whole-tree fmt/lint always run under --full-check; otherwise scoped below.
+declare -a changed_nix_files=()
+for f in "${changed_files[@]:-}"; do
+  [[ "$f" == *.nix && -f "$f" ]] && changed_nix_files+=("$f")
+done
+
 echo
 echo "Checking Nix formatting with nixpkgs-fmt..."
-nix run "${NIX_EVAL_FLAGS[@]}" github:NixOS/nixpkgs/nixos-25.11#nixpkgs-fmt -- --check .
+if $full_check; then
+  nix run "${NIX_EVAL_FLAGS[@]}" github:NixOS/nixpkgs/nixos-25.11#nixpkgs-fmt -- --check .
+elif [[ ${#changed_nix_files[@]} -gt 0 ]]; then
+  nix run "${NIX_EVAL_FLAGS[@]}" github:NixOS/nixpkgs/nixos-25.11#nixpkgs-fmt -- --check "${changed_nix_files[@]}"
+else
+  echo "No changed .nix files; skipping."
+fi
 
 echo
 echo "Running statix lint..."
-nix run "${NIX_EVAL_FLAGS[@]}" github:NixOS/nixpkgs/nixos-25.11#statix -- check .
+if $full_check; then
+  nix run "${NIX_EVAL_FLAGS[@]}" github:NixOS/nixpkgs/nixos-25.11#statix -- check .
+elif [[ ${#changed_nix_files[@]} -gt 0 ]]; then
+  for f in "${changed_nix_files[@]}"; do
+    nix run "${NIX_EVAL_FLAGS[@]}" github:NixOS/nixpkgs/nixos-25.11#statix -- check "$f"
+  done
+else
+  echo "No changed .nix files; skipping."
+fi
+
+# Figure out which hosts/packages this run needs to eval (and, under
+# --dry-run, build). full_check always means "everything"; otherwise a
+# change to flake.nix/flake.lock/variables.nix/modules/common/* (repo-wide
+# inputs) or to any other modules/*.nix outside platforms//build-types
+# (whose blast radius isn't safely inferable from the path alone -- see
+# CLAUDE.md's "Grep modules/build-types/*.nix for each build type's imports
+# list") also falls back to everything, on the same reasoning CLAUDE.md
+# already gives interactive sessions for when to run the full sweep.
+# Anything more targeted -- a host.nix, a platform module, a build-type
+# module -- narrows to just the hosts it can affect.
+declare -A affected_hosts=()
+eval_packages=false
+
+if $full_check; then
+  for h in "${all_hosts[@]}"; do affected_hosts[$h]=1; done
+  eval_packages=true
+else
+  full_fallback=false
+  for f in "${changed_files[@]:-}"; do
+    case "$f" in
+      flake.nix|flake.lock|variables.nix|modules/common/*)
+        full_fallback=true
+        ;;
+    esac
+  done
+
+  if ! $full_fallback; then
+    for f in "${changed_files[@]:-}"; do
+      case "$f" in
+        hosts/*/*)
+          hostdir="${f#hosts/}"
+          hostdir="${hostdir%%/*}"
+          while IFS= read -r t; do
+            [[ -n "$t" ]] && affected_hosts[$t]=1
+          done < <(host_targets_for_dir "$hostdir")
+          ;;
+        modules/platforms/*.nix)
+          platform="$(basename "$f" .nix)"
+          for h in "${all_hosts[@]}"; do
+            [[ "$h" == "${platform}-"* ]] && affected_hosts[$h]=1
+          done
+          ;;
+        modules/build-types/*.nix)
+          buildtype="$(basename "$f" .nix)"
+          for h in "${all_hosts[@]}"; do
+            [[ "$h" == *"-${buildtype}" ]] && affected_hosts[$h]=1
+          done
+          ;;
+        modules/installer/*)
+          # iso.nix (imported by both the "installer" nixosConfigurations
+          # target and netbootSystem, which backs packages.pxe) pulls in
+          # common.nix, so a common.nix change reaches all three.
+          affected_hosts[installer]=1
+          eval_packages=true
+          ;;
+        modules/pxe-boot/*)
+          # stage-installer-artifacts.nix is imported by
+          # modules/build-types/pxe-boot.nix only -- same blast radius as a
+          # build-types/*.nix change, not a packages one.
+          for h in "${all_hosts[@]}"; do
+            [[ "$h" == *"-pxe-boot" ]] && affected_hosts[$h]=1
+          done
+          ;;
+        modules/*)
+          full_fallback=true
+          ;;
+      esac
+    done
+  fi
+
+  if $full_fallback; then
+    echo
+    echo "Changed files affect shared config; falling back to evaluating every host/package."
+    for h in "${all_hosts[@]}"; do affected_hosts[$h]=1; done
+    eval_packages=true
+  fi
+fi
+
+mapfile -t hosts < <(for h in "${!affected_hosts[@]}"; do echo "$h"; done | sort)
 
 echo
-echo "Evaluating host toplevel derivations..."
+if [[ ${#hosts[@]} -eq 0 ]]; then
-for host in $hosts; do
+  echo "No hosts affected by changed files; skipping host eval."
-  echo "==> $host"
+else
-  nix eval --raw "${NIX_EVAL_FLAGS[@]}" ".#nixosConfigurations.${host}.config.system.build.toplevel.drvPath"
+  echo "Evaluating host toplevel derivations (${scope_desc})..."
+  for host in "${hosts[@]}"; do
+    echo "==> $host"
+    nix eval --raw "${NIX_EVAL_FLAGS[@]}" ".#nixosConfigurations.${host}.config.system.build.toplevel.drvPath"
 
-  # lxc-* hosts deploy via a directly pct-restore-able tarball instead of
+    # lxc-* hosts deploy via a directly pct-restore-able tarball instead of
-  # nixos-install (see docs/auto-installer.md); proxmox-* hosts can
+    # nixos-install (see docs/auto-installer.md); proxmox-* hosts can
-  # alternatively be built as a standalone disk image (see
+    # alternatively be built as a standalone disk image (see
-  # docs/proxmox-images.md). Both are otherwise-unvalidated buildable
+    # docs/proxmox-images.md). Both are otherwise-unvalidated buildable
-  # surface, easy to silently break without this.
+    # surface, easy to silently break without this.
-  case "$host" in
+    case "$host" in
-    lxc-*)
+      lxc-*)
-      echo "==> $host (tarball)"
+        echo "==> $host (tarball)"
-      nix eval --raw "${NIX_EVAL_FLAGS[@]}" ".#nixosConfigurations.${host}.config.system.build.tarball.drvPath"
+        nix eval --raw "${NIX_EVAL_FLAGS[@]}" ".#nixosConfigurations.${host}.config.system.build.tarball.drvPath"
-      ;;
+        ;;
-    proxmox-*)
+      proxmox-*)
-      echo "==> $host (diskoImagesScript)"
+        echo "==> $host (diskoImagesScript)"
-      nix eval --raw "${NIX_EVAL_FLAGS[@]}" ".#nixosConfigurations.${host}.config.system.build.diskoImagesScript.drvPath"
+        nix eval --raw "${NIX_EVAL_FLAGS[@]}" ".#nixosConfigurations.${host}.config.system.build.diskoImagesScript.drvPath"
-      ;;
+        ;;
-  esac
+    esac
-done
+  done
+fi
 
 echo
-echo "Evaluating buildable packages..."
+if ! $eval_packages; then
-packages="$(nix eval --json "${NIX_EVAL_FLAGS[@]}" .#packages.x86_64-linux --apply builtins.attrNames | jq -r '.[]')"
+  echo "No packages affected by changed files; skipping package eval."
-for pkg in $packages; do
+else
-  echo "==> packages.x86_64-linux.${pkg}"
+  echo "Evaluating buildable packages..."
-  nix eval --raw "${NIX_EVAL_FLAGS[@]}" ".#packages.x86_64-linux.${pkg}"
+  for pkg in "${all_packages[@]}"; do
-done
+    echo "==> packages.x86_64-linux.${pkg}"
+    nix eval --raw "${NIX_EVAL_FLAGS[@]}" ".#packages.x86_64-linux.${pkg}"
+  done
+fi
 
-if [[ "$MODE" == "dry-run" ]]; then
+if $dry_run; then
   echo
-  echo "Running dry-run builds for all hosts. This will not create result symlinks."
+  echo "Running dry-run builds for the active scope. This will not create result symlinks."
-  for host in $hosts; do
+  for host in "${hosts[@]:-}"; do
     echo "==> Dry-run build: $host"
     nix build --dry-run --no-link "${NIX_EVAL_FLAGS[@]}" ".#nixosConfigurations.${host}.config.system.build.toplevel"
 
@@ -91,12 +285,14 @@ if [[ "$MODE" == "dry-run" ]]; then
     esac
   done
 
-  echo
+  if $eval_packages; then
-  echo "Running dry-run builds for all packages."
+    echo
-  for pkg in $packages; do
+    echo "Running dry-run builds for packages."
-    echo "==> Dry-run build: packages.x86_64-linux.${pkg}"
+    for pkg in "${all_packages[@]}"; do
-    nix build --dry-run --no-link "${NIX_EVAL_FLAGS[@]}" ".#packages.x86_64-linux.${pkg}"
+      echo "==> Dry-run build: packages.x86_64-linux.${pkg}"
-  done
+      nix build --dry-run --no-link "${NIX_EVAL_FLAGS[@]}" ".#packages.x86_64-linux.${pkg}"
+    done
+  fi
 fi
 
 echo

scripts/codex-setup.sh

@@ -82,13 +82,6 @@ if ! command -v jq >/dev/null 2>&1; then
 fi
 
 echo "Available NixOS hosts:"
-hosts="$(list_flake_targets .)"
+list_flake_targets .
-echo "$hosts"
 
-echo "Evaluating all host toplevel derivations..."
+echo "Codex setup complete. Run bash scripts/codex-maintenance.sh to validate changes."
-for host in $hosts; do
-  echo "==> Evaluating $host"
-  nix eval --raw "${NIX_EVAL_FLAGS[@]}" ".#nixosConfigurations.${host}.config.system.build.toplevel.drvPath"
-done
-
-echo "Codex setup complete."

scripts/env.sh

@@ -3,10 +3,10 @@
 # second copy of these values in every script:
 #   source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/env.sh"
 # Every variable can still be overridden per-invocation via the
-# environment (e.g. PROXMOX_STORAGE=tank-nvme ./scripts/create-proxmox-resource.sh ...)
+# environment (e.g. PROXMOX_STORAGE=tank-nvme ./scripts/proxmox/create-proxmox-resource.sh ...)
 # since each one only sets a default if unset.
 
-# SSH-reachable Proxmox node that scripts/create-proxmox-resource.sh runs
+# SSH-reachable Proxmox node that scripts/proxmox/create-proxmox-resource.sh runs
 # pct/qm on. Matches the Proxmox web UI hostname already used in
 # hosts/nixos/home.nix's desktop shortcuts (pve.<homeDomain> from
 # variables.nix) -- change this if that's not actually reachable over SSH,
@@ -15,7 +15,7 @@
 : "${PROXMOX_SSH_USER:=root}"
 
 # Where this flake repo lives on the Proxmox node itself.
-# scripts/create-proxmox-resource.sh builds images directly on the node
+# scripts/proxmox/create-proxmox-resource.sh builds images directly on the node
 # instead of transferring them over the network -- it clones the repo here
 # (from this checkout's own `origin` remote) the first time it doesn't
 # find it, installing build tooling via scripts/codex-setup.sh, then

scripts/lib/confirm.sh

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+# Shared "type X to confirm" prompt for scripts/proxmox/create-proxmox-resource.sh
+# (--modify, and replacing an existing --allow-duplicate-host resource) and
+# scripts/secrets/sync-host-keys.sh (--regenerate-all-keys) -- three destructive
+# confirmations that all work the same way (echo the expected value back
+# exactly), kept in one place so the prompt/comparison logic can't drift.
+# Source alongside env.sh:
+#   source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/lib/confirm.sh"
+#
+# Deliberately does NOT print anything on mismatch or decide exit-vs-return
+# -- callers vary on both (a top-level script exits, a subcommand function
+# returns; wording differs too), so that stays at the call site.
+
+# confirm_typed <expected> <prompt>
+# Prints <prompt> via `read -rp`, then reports (via exit status) whether the
+# typed input matched <expected> exactly.
+confirm_typed() {
+  local expected="$1" prompt="$2" input
+  read -rp "$prompt" input
+  [[ "$input" == "$expected" ]]
+}

scripts/lib/sops-age.sh

@@ -0,0 +1,52 @@
+#!/usr/bin/env bash
+# Shared sops/age helpers for scripts/secrets/backup-admin-key.sh,
+# scripts/secrets/rotate-admin-key.sh, and scripts/secrets/sync-host-keys.sh -- all three
+# derive an age public key from a private identity file the same way, two
+# of them resolve the same sops/age default key-file path, and two of them
+# run `sops updatekeys` the same way. Kept in one place so they can't drift
+# apart. Source alongside env.sh:
+#   source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/lib/sops-age.sh"
+#
+# Uses NIX_OPTS (an array of extra `nix-shell` options -- see env.sh's
+# nix_extra_opts) if the caller has already set it, same convention as
+# lib/ssh-host-keys.sh. Falls back to no extra options if the caller never
+# sourced env.sh.
+if ! declare -p NIX_OPTS >/dev/null 2>&1; then
+  declare -a NIX_OPTS=()
+fi
+
+# sops/age's own default identity-file resolution order, minus $SOPS_AGE_KEY
+# itself (an inline identity, not a path -- callers that accept it check it
+# separately, before falling back to this).
+: "${DEFAULT_SOPS_AGE_KEY_FILE:=${SOPS_AGE_KEY_FILE:-${XDG_CONFIG_HOME:-$HOME/.config}/sops/age/keys.txt}}"
+
+# age_pubkey_from_identity_file <identity-file>
+# Prints the age public key for a private identity file (age-keygen -y).
+age_pubkey_from_identity_file() {
+  local identity_file="$1"
+  nix-shell "${NIX_OPTS[@]}" -p age --run "age-keygen -y '${identity_file}'"
+}
+
+# sops_yaml_admin_pubkey <sops-yaml-path>
+# Prints .sops.yaml's current &admin age public key, or empty (not an error
+# under set -e) if no such anchor line exists -- callers that need to treat
+# "missing" as fatal check for an empty result themselves.
+sops_yaml_admin_pubkey() {
+  local sops_yaml="$1"
+  grep -E '^  - &admin age1' "$sops_yaml" 2>/dev/null | awk '{print $NF}' || true
+}
+
+# sops_updatekeys <secrets-file> [key-file]
+# Re-encrypts <secrets-file> for .sops.yaml's current recipient set. If
+# <key-file> is given, decrypts with that identity (SOPS_AGE_KEY_FILE)
+# instead of whatever's ambient -- needed when the ambient default key
+# doesn't match yet (e.g. mid-rotation, decrypting with the outgoing key).
+sops_updatekeys() {
+  local secrets_file="$1" key_file="${2:-}"
+  if [[ -n "$key_file" ]]; then
+    SOPS_AGE_KEY_FILE="$key_file" nix-shell "${NIX_OPTS[@]}" -p sops --run \
+      "sops updatekeys --yes '${secrets_file}'"
+  else
+    nix-shell "${NIX_OPTS[@]}" -p sops --run "sops updatekeys --yes '${secrets_file}'"
+  fi
+}

scripts/lib/ssh-host-keys.sh

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
-# Shared SSH-host-key / age-conversion helpers for scripts/sync-host-keys.sh
+# Shared SSH-host-key / age-conversion helpers for scripts/secrets/sync-host-keys.sh
-# and scripts/prepare-host-key.sh -- both generate the same kind of key
+# and scripts/secrets/prepare-host-key.sh -- both generate the same kind of key
 # (ed25519, no passphrase, the sops-nix age-derivation input) and convert it
 # to an age recipient the same way; kept in one place so the two can't
 # drift apart.

scripts/proxmox/create-proxmox-resource.sh

@@ -13,9 +13,9 @@
 # alone wouldn't carry it) before building.
 #
 # Usage:
-#   scripts/create-proxmox-resource.sh --type lxc|vm --host <name> [options]
+#   scripts/proxmox/create-proxmox-resource.sh --type lxc|vm --host <name> [options]
-#   scripts/create-proxmox-resource.sh --type lxc|vm --list
+#   scripts/proxmox/create-proxmox-resource.sh --type lxc|vm --list
-#   scripts/create-proxmox-resource.sh --modify --vmid <n> [--cores N] [--memory MB] [--grow-disk GB]
+#   scripts/proxmox/create-proxmox-resource.sh --modify --vmid <n> [--cores N] [--memory MB] [--grow-disk GB]
 #
 # SAFETY:
 #   - The default (create) mode only ever creates a NEW resource -- it
@@ -41,13 +41,15 @@
 # See --help for the full option list.
 set -euo pipefail
 
-repo_root="$(cd "$(dirname "$0")/.." && pwd)"
+repo_root="$(cd "$(dirname "$0")/../.." && pwd)"
-# shellcheck source=env.sh
+# shellcheck source=../env.sh
 source "${repo_root}/scripts/env.sh"
-# shellcheck source=lib/nix-eval.sh
+# shellcheck source=../lib/nix-eval.sh
 source "${repo_root}/scripts/lib/nix-eval.sh"
+# shellcheck source=../lib/confirm.sh
+source "${repo_root}/scripts/lib/confirm.sh"
 
-sync_keys="${repo_root}/scripts/sync-host-keys.sh"
+sync_keys="${repo_root}/scripts/secrets/sync-host-keys.sh"
 
 usage() {
   cat <<EOF
@@ -230,8 +232,7 @@ cmd_modify() {
   fi
 
   echo
-  read -rp "Type the VMID (${vmid}) to confirm these changes: " confirm
+  if ! confirm_typed "$vmid" "Type the VMID (${vmid}) to confirm these changes: "; then
-  if [[ "$confirm" != "$vmid" ]]; then
     echo "Cancelled -- input didn't match ${vmid}."
     exit 1
   fi
@@ -429,8 +430,7 @@ REMOTE_SCRIPT
       echo "  - ${kind} VMID ${id} (${n})"
     done
     echo
-    read -rp "Type the hostname (${host}) to confirm destroying the above and replacing it: " confirm
+    if ! confirm_typed "$host" "Type the hostname (${host}) to confirm destroying the above and replacing it: "; then
-    if [[ "$confirm" != "$host" ]]; then
       echo "Cancelled -- input didn't match ${host}." >&2
       exit 1
     fi
@@ -524,7 +524,7 @@ ensure_remote_repo() {
   echo
   echo "==> Ensuring ${remote_repo_dir} exists and is current on ${node}..."
   if [[ "$dry_run" -eq 1 ]]; then
-    echo "[dry-run] would ensure ${remote_repo_dir} exists on ${node} (clone if missing, git pull if present), and would verify/bootstrap build tooling there (scripts/codex-setup.sh) if \`nix\` isn't already on PATH -- and if that bootstrap actually ran, would also configure ${node} as a nix-cache client (scripts/configure-nix-cache-client.sh)"
+    echo "[dry-run] would ensure ${remote_repo_dir} exists on ${node} (clone if missing, git pull if present), and would verify/bootstrap build tooling there (scripts/codex-setup.sh) if \`nix\` isn't already on PATH -- and if that bootstrap actually ran, would also configure ${node} as a nix-cache client (scripts/proxmox/configure-nix-cache-client.sh)"
     return
   fi
 
@@ -583,7 +583,7 @@ ensure_remote_repo() {
     # above -- ssh's non-interactive command execution won't have picked
     # up a freshly single-user-installed `nix` otherwise.
     echo "==> Configuring ${node} as a nix-cache substituter/remote-builder client..."
-    if ! ssh "$ssh_target" "cd '${remote_repo_dir}' && . scripts/lib/nix-bootstrap.sh && ensure_nix_profile && bash scripts/configure-nix-cache-client.sh"; then
+    if ! ssh "$ssh_target" "cd '${remote_repo_dir}' && . scripts/lib/nix-bootstrap.sh && ensure_nix_profile && bash scripts/proxmox/configure-nix-cache-client.sh"; then
       echo "WARNING: configure-nix-cache-client.sh failed on ${node} -- continuing without it (${node} will build from source / against cache.nixos.org only)." >&2
     fi
   fi

scripts/secrets/backup-admin-key.sh

@@ -6,7 +6,7 @@
 # copy is ever lost, or to run either script from a different machine.
 #
 # Usage:
-#   scripts/backup-admin-key.sh <dest-path> [--key-file <path>] [--force] [--dry-run]
+#   scripts/secrets/backup-admin-key.sh <dest-path> [--key-file <path>] [--force] [--dry-run]
 #
 # Source key resolution matches sops/age's own default order:
 #   $SOPS_AGE_KEY (inline identity text) if set, else
@@ -15,11 +15,13 @@
 #   ${XDG_CONFIG_HOME:-$HOME/.config}/sops/age/keys.txt
 set -euo pipefail
 
-repo_root="$(cd "$(dirname "$0")/.." && pwd)"
+repo_root="$(cd "$(dirname "$0")/../.." && pwd)"
 sops_yaml="${repo_root}/.sops.yaml"
 
-# shellcheck source=env.sh
+# shellcheck source=../env.sh
 source "${repo_root}/scripts/env.sh"
+# shellcheck source=../lib/sops-age.sh
+source "${repo_root}/scripts/lib/sops-age.sh"
 
 # Pin cwd for the same reason rotate-admin-key.sh does: age/sops calls
 # below should never depend on wherever the caller's shell happened to be.
@@ -43,7 +45,7 @@ EOF
 
 dry_run=0
 force=0
-key_file="${SOPS_AGE_KEY_FILE:-${XDG_CONFIG_HOME:-$HOME/.config}/sops/age/keys.txt}"
+key_file="$DEFAULT_SOPS_AGE_KEY_FILE"
 args=()
 
 while [[ $# -gt 0 ]]; do
@@ -103,13 +105,13 @@ scratch="$(mktemp)"
 trap 'rm -f "$scratch"' EXIT
 ( umask 077; printf '%s\n' "$src_content" > "$scratch" )
 
-src_pub="$(nix-shell "${NIX_OPTS[@]}" -p age --run "age-keygen -y '$scratch'")" || {
+src_pub="$(age_pubkey_from_identity_file "$scratch")" || {
   echo "ERROR: source doesn't look like a valid age identity (age-keygen -y failed)." >&2
   exit 1
 }
 echo "    public key: ${src_pub}"
 
-current_admin_pub="$(grep -E '^  - &admin age1' "$sops_yaml" 2>/dev/null | awk '{print $NF}' || true)"
+current_admin_pub="$(sops_yaml_admin_pubkey "$sops_yaml")"
 if [[ -n "$current_admin_pub" && "$current_admin_pub" != "$src_pub" ]]; then
   echo "NOTE: this key does not match .sops.yaml's current &admin entry (${current_admin_pub})."
   echo "      Backing it up anyway -- this script doesn't require it to be the admin key."
@@ -131,7 +133,7 @@ fi
 mkdir -p "$(dirname "$dest")"
 install -m 600 "$scratch" "$dest"
 
-dest_pub="$(nix-shell "${NIX_OPTS[@]}" -p age --run "age-keygen -y '$dest'")"
+dest_pub="$(age_pubkey_from_identity_file "$dest")"
 if [[ "$dest_pub" != "$src_pub" ]]; then
   echo "ERROR: ${dest} was written but its public key doesn't match the source -- investigate before relying on this backup." >&2
   exit 1
@@ -144,5 +146,5 @@ Done. Backed up to: ${dest}
 
 This is a private key -- store it somewhere offline/secure, not in this
 repo or anywhere it'd get committed. Restore it with:
-  scripts/rotate-admin-key.sh ${dest}
+  scripts/secrets/rotate-admin-key.sh ${dest}
 EOF

scripts/secrets/prepare-host-key.sh

@@ -2,7 +2,7 @@
 # Generates a new machine's SSH host key by an arbitrary name, before it
 # necessarily has a flake target yet -- prints the .sops.yaml snippet to
 # add by hand. For any host that already has a flake target,
-# scripts/sync-host-keys.sh <target> does this same job plus the
+# scripts/secrets/sync-host-keys.sh <target> does this same job plus the
 # .sops.yaml/key_groups registration and re-encryption automatically; use
 # this script only to pre-generate a key ahead of adding the flake target
 # itself.
@@ -22,13 +22,13 @@
 # new machine.
 set -euo pipefail
 
-repo_root="$(cd "$(dirname "$0")/.." && pwd)"
+repo_root="$(cd "$(dirname "$0")/../.." && pwd)"
-# shellcheck source=env.sh
+# shellcheck source=../env.sh
 source "${repo_root}/scripts/env.sh"
-# shellcheck source=lib/ssh-host-keys.sh
+# shellcheck source=../lib/ssh-host-keys.sh
 source "${repo_root}/scripts/lib/ssh-host-keys.sh"
 
-hostname="${1:?usage: scripts/prepare-host-key.sh <hostname>}"
+hostname="${1:?usage: scripts/secrets/prepare-host-key.sh <hostname>}"
 sops_yaml="${repo_root}/.sops.yaml"
 
 if [[ ! -f "$sops_yaml" ]]; then

scripts/secrets/rotate-admin-key.sh

@@ -10,7 +10,7 @@
 # sync-host-keys.sh print when they bootstrap a brand-new, not-yet-trusted
 # age key on a machine that's never had admin access before:
 #
-#   scripts/rotate-admin-key.sh /path/to/backed-up/admin/keys.txt
+#   scripts/secrets/rotate-admin-key.sh /path/to/backed-up/admin/keys.txt
 #
 # The backup key's *public* key must match .sops.yaml's current &admin
 # entry -- this script verifies that by deriving it, it doesn't just trust
@@ -19,11 +19,13 @@
 # the common case is just pointing this at the restored backup.
 set -euo pipefail
 
-repo_root="$(cd "$(dirname "$0")/.." && pwd)"
+repo_root="$(cd "$(dirname "$0")/../.." && pwd)"
 sops_yaml="${repo_root}/.sops.yaml"
 
-# shellcheck source=env.sh
+# shellcheck source=../env.sh
 source "${repo_root}/scripts/env.sh"
+# shellcheck source=../lib/sops-age.sh
+source "${repo_root}/scripts/lib/sops-age.sh"
 
 # sops resolves .sops.yaml by walking up from the process's cwd, not from
 # the target file's own path -- if this script were invoked from somewhere
@@ -53,7 +55,7 @@ EOF
 }
 
 dry_run=0
-new_key_file="${SOPS_AGE_KEY_FILE:-${XDG_CONFIG_HOME:-$HOME/.config}/sops/age/keys.txt}"
+new_key_file="$DEFAULT_SOPS_AGE_KEY_FILE"
 args=()
 
 while [[ $# -gt 0 ]]; do
@@ -93,13 +95,9 @@ backup_key="${args[0]}"
 
 nix_extra_opts
 
-age_pub() {
-  nix-shell "${NIX_OPTS[@]}" -p age --run "age-keygen -y '$1'"
-}
-
 echo "==> Deriving public keys..."
-old_pub="$(age_pub "$backup_key")"
+old_pub="$(age_pubkey_from_identity_file "$backup_key")"
-new_pub="$(age_pub "$new_key_file")"
+new_pub="$(age_pubkey_from_identity_file "$new_key_file")"
 echo "    backup (old admin) key: ${old_pub}"
 echo "    new admin key:          ${new_pub}"
 
@@ -108,12 +106,11 @@ if [[ "$old_pub" == "$new_pub" ]]; then
   exit 1
 fi
 
-current_admin_line="$(grep -E '^  - &admin age1' "$sops_yaml" || true)"
+current_admin_pub="$(sops_yaml_admin_pubkey "$sops_yaml")"
-if [[ -z "$current_admin_line" ]]; then
+if [[ -z "$current_admin_pub" ]]; then
   echo "ERROR: couldn't find a '&admin age1...' line in ${sops_yaml}." >&2
   exit 1
 fi
-current_admin_pub="$(awk '{print $NF}' <<<"$current_admin_line")"
 
 if [[ "$current_admin_pub" != "$old_pub" ]]; then
   echo "ERROR: ${backup_key} doesn't match the current &admin key in .sops.yaml." >&2
@@ -129,9 +126,17 @@ if [[ "${#secrets_files[@]}" -eq 0 ]]; then
   exit 1
 fi
 
+# sops_can_decrypt <key-file> <secrets-file>: used both to confirm the
+# backup key still works before touching anything, and again after
+# rotation to confirm the new key does too.
+sops_can_decrypt() {
+  local key_file="$1" secrets_file="$2"
+  SOPS_AGE_KEY_FILE="$key_file" nix-shell "${NIX_OPTS[@]}" -p sops --run \
+    "sops -d '${secrets_file}'" >/dev/null
+}
+
 echo "==> Confirming the backup key can actually decrypt..."
-if ! SOPS_AGE_KEY_FILE="$backup_key" nix-shell "${NIX_OPTS[@]}" -p sops --run \
+if ! sops_can_decrypt "$backup_key" "${secrets_files[0]}"; then
-  "sops -d '${secrets_files[0]}'" >/dev/null; then
   echo "ERROR: backup key failed to decrypt $(basename "${secrets_files[0]}") -- aborting." >&2
   exit 1
 fi
@@ -162,14 +167,12 @@ echo "    Updated."
 echo "==> Re-encrypting secrets/*.yaml for the new recipient set..."
 for f in "${secrets_files[@]}"; do
   echo "==> $(basename "$f")"
-  SOPS_AGE_KEY_FILE="$backup_key" nix-shell "${NIX_OPTS[@]}" -p sops --run \
+  sops_updatekeys "$f" "$backup_key"
-    "sops updatekeys --yes '${f}'"
 done
 
 echo "==> Verifying the new key can decrypt everything..."
 for f in "${secrets_files[@]}"; do
-  if ! SOPS_AGE_KEY_FILE="$new_key_file" nix-shell "${NIX_OPTS[@]}" -p sops --run \
+  if ! sops_can_decrypt "$new_key_file" "$f"; then
-    "sops -d '${f}'" >/dev/null; then
     echo "ERROR: new key failed to decrypt $(basename "$f") after rotation -- investigate before committing." >&2
     exit 1
   fi

scripts/secrets/sync-host-keys.sh

@@ -24,17 +24,21 @@
 # ever touches keys it itself manages.
 set -euo pipefail
 
-repo_root="$(cd "$(dirname "$0")/.." && pwd)"
+repo_root="$(cd "$(dirname "$0")/../.." && pwd)"
 sops_yaml="${repo_root}/.sops.yaml"
 keydir="${repo_root}/host-keys"
 editor="${repo_root}/scripts/lib/sync-host-keys-edit-sops.py"
 
-# shellcheck source=env.sh
+# shellcheck source=../env.sh
 source "${repo_root}/scripts/env.sh"
-# shellcheck source=lib/nix-eval.sh
+# shellcheck source=../lib/nix-eval.sh
 source "${repo_root}/scripts/lib/nix-eval.sh"
-# shellcheck source=lib/ssh-host-keys.sh
+# shellcheck source=../lib/ssh-host-keys.sh
 source "${repo_root}/scripts/lib/ssh-host-keys.sh"
+# shellcheck source=../lib/sops-age.sh
+source "${repo_root}/scripts/lib/sops-age.sh"
+# shellcheck source=../lib/confirm.sh
+source "${repo_root}/scripts/lib/confirm.sh"
 
 mkdir -p "$keydir"
 
@@ -78,7 +82,7 @@ ensure_admin_decrypt_key() {
     return
   fi
 
-  local key_file="${SOPS_AGE_KEY_FILE:-${XDG_CONFIG_HOME:-$HOME/.config}/sops/age/keys.txt}"
+  local key_file="$DEFAULT_SOPS_AGE_KEY_FILE"
 
   if [[ -s "$key_file" ]]; then
     echo "Found existing sops age key at ${key_file}."
@@ -97,7 +101,7 @@ ensure_admin_decrypt_key() {
   mkdir -p "$(dirname "$key_file")"
   nix-shell "${NIX_OPTS[@]}" -p age --run "age-keygen -o '${key_file}'" 2>&1 | grep -v "^Public key:" || true
   local new_pub
-  new_pub="$(nix-shell "${NIX_OPTS[@]}" -p age --run "age-keygen -y '${key_file}'")"
+  new_pub="$(age_pubkey_from_identity_file "$key_file")"
 
   cat <<EOF
 
@@ -239,7 +243,7 @@ apply_edit_plan() {
       while IFS= read -r basename; do
         [[ -z "$basename" ]] && continue
         echo "==> secrets/${basename}"
-        nix-shell "${NIX_OPTS[@]}" -p sops --run "sops updatekeys --yes '${repo_root}/secrets/${basename}'"
+        sops_updatekeys "${repo_root}/secrets/${basename}"
       done <<<"$changed"
     fi
   fi
@@ -359,8 +363,7 @@ cmd_regenerate_all() {
   echo "image/tarball before it can decrypt secrets again."
 
   if [[ "$dry_run" -ne 1 ]]; then
-    read -rp "Type REGENERATE to confirm: " confirm
+    if ! confirm_typed "REGENERATE" "Type REGENERATE to confirm: "; then
-    if [[ "$confirm" != "REGENERATE" ]]; then
       echo "Cancelled."
       return
     fi

secrets/nix-cache.yaml

@@ -4,31 +4,31 @@ sops:
     age:
         - enc: |
             -----BEGIN AGE ENCRYPTED FILE-----
-            YWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSBmOHlPcGZvN3o5aEZCcFdz
+            YWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSBPWE1HTUhiSUp5ZEUwWEpI
-            WlYydFdoQ0ZHbElMdTRkZWljMmoxTHZqNjJZCnE3cmgzKzZya3FROEczbHVveDND
+            bGpkZlBIMUo5ZlYrQ09SN3Q1a0ZkQ0ZnOEhVCnJPNEZQenVWWGZiODlzQzNEc1Zq
-            VnEzRW12cnRKdzhkZm5uTXpkTEtrNUEKLS0tIHFDbkc4Mk4wVlM2R29zZXYwR2Ri
+            c3l4OWZJTElJc2Y2UE15OGtEUzhyY1EKLS0tIHNJUStyWnlQWjZBbEZjQ3UwdUpz
-            ODBML1p4eUZiZldYUERQTUhTU1llV0UKxjvH6zbW6wKghzR1o34CyKPEa2FqZmo0
+            ZndoUDR6bisrNGJCUHk3TGI4bTZaMFUK87fFsm9ne9s+PK2pcwtrDjqyGBss2r2E
-            PxgqyuXkIwas9soXVAkScx7ElaV09Fjaj+mDrKwi4a+DwdoSP7czyA==
+            8lhqoeiKZ2j96z8kP/7ChzovwTCmqdcmAQuyNQD+ZAFijseipSvfbQ==
             -----END AGE ENCRYPTED FILE-----
           recipient: age1njap586hc0q43kr03g6c8eqhdsmk8zcafkl3f83xwlc2gqhlmfgs4tmwad
         - enc: |
             -----BEGIN AGE ENCRYPTED FILE-----
-            YWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSB0VDBXYUZNbnpEZHlqV05C
+            YWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSBUYi9SRFFGV3Z6cFd2Znk5
-            WWxQZjVYcWlZeXlGc0RiaUpERzR0T21CWWtBCkM0dW5kYlFNK1RGSzRudFZ2Z0t3
+            b2FLbWtzTllJMDBUaGk0NTViOTNBa2hQclVZClZHKzNhbGVjQUJhWkFWdTFBMG5a
-            aVBreElGM1BIT0RzQkxTVTA3S2NhQncKLS0tIERyTU8zWWRTRm95SmRZQ1BhalVV
+            cUFJdUdyVG5HQXJRRnJId3hqRTN2cXMKLS0tIEFMRjh3WE1ON0U2TTNTZ3hxMTR4
-            SVdBajN1V1BuM2s4K216S3c0VHczNlkKM5jvsSEfCBA5uZRjBJNbM91lLRQkj+jK
+            ZGRlemlIbDZKeExmVHROc3Eyak5DdzQKaLwIVDi6BN4cxpVxJoqTYvJETPOp4thc
-            rM5uSfGLTvSjPgXIMIq03OXxH1CE7GoKxAPwFrJdAFMMQcutIethhw==
+            l9uVMvIGuEsEZgDsvShw1dYLljd+uGy/A+dXbcxIUCP/mmPkwmd1Pw==
             -----END AGE ENCRYPTED FILE-----
           recipient: age120le4a5l8dh3lyfgvmj3d9ksmej6ajs5mer5y7r0vfg3x9fn69dqf8xgzu
         - enc: |
             -----BEGIN AGE ENCRYPTED FILE-----
-            YWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSAvbk9tRE9jYkpxNThQeElH
+            YWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSArOWovSW9DeFpxL0VDUDQ3
-            dWpKYThDb1ZkUWtMWlRxc2tYbjhBbEFEcWtVCkNiK0NBRko2TkJQdUVtdGtHNGcv
+            SHUwTzJVZUtPV01ZRkdCUXZGL2lTRCtCNFNnCjBSNExqRW5mTEN5SFVucHJHSzZt
-            andSaUlKSFA4THRyZXNTYmI0Yk5WbmsKLS0tIHlQTUtpWDdPeTVZL0M1RElRdFNk
+            cDlNc3BjY3M1c1k1Z2tkVEg4R1pacGsKLS0tIEFWbHNKZW0vbVh1Y2VhQW93OUwx
-            QWlGdFo5NkZWSmY0YXdpNzNUQnlsK3MKtzC0bM7Ek+K73nMranOA1Mc98RUnYnq1
+            MWV0eW9sOXdQd0l2ZjlWOEVVc1dwcTgK2s4p9xoNkawH2OkGsl80bNIo3ad5vn4W
-            hAt0QEFKWK4QVKubaN/rG3AzE0U7qPKWHTzoxgnAiL3WyV9teLW+iA==
+            Z2w+jwppSoUmbQnD3WFbLmSSxmuobmU8HILwElv6SZu+KE3aspF6XA==
             -----END AGE ENCRYPTED FILE-----
-          recipient: age164px2a8e48ptsf9ngtan38aa6jls4jdl26mzrgzf6sn3vcvt49hqjrgr8w
+          recipient: age1xjst4frdh0th6q8m7p7u9g5af7ty5jqeum0p6z8a52a9q7st7ewqw8yl9j
     lastmodified: "2026-07-19T23:30:21Z"
     mac: ENC[AES256_GCM,data:kLGE2xawQT7mx+sfw68hmGk5nCEGiEjZrqTEl9B1dtQmTrMwmoVr/1RISi4LfJrwxy31mDgff4lcIL4wIJuM373uk3X8j4RNyYQNTfKEkORT6r8NHeepNs267O77pKGd7OmcM4MT/BqOnB8ELS7Wlf2ect7CAlvUUVyc8icxgZE=,iv:EYLDsHYHZ1XOQXafOTqHHWpk/OBNq/R6IJnOBYV33E4=,tag:thxrCPC5oGvDjhK7Dz87YA==,type:str]
     unencrypted_suffix: _unencrypted

variables.nix

@@ -38,6 +38,7 @@
     "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIIGtOWOCS+ImHc7NehguoyD7PbonGosKMZqc9+QR3v/h root@nixos"
     "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIHxXTQxFnArK5HXG7czeoybZebCGfxpUdusJkPn+BCSp root@server"
     "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAICMJhrfFayLBG+gWtO6oAvgambw5nWWgztiTFEaaaVRH debian@surface"
+    "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIJEj26SL/emsVjW2YhRucJVp2kTz8WgcEQgjBEBLRikk root@claude"
   ];
 
   # Admin SSH public key, authorized on the primary user of every host and