diff --git a/CHANGELOG.md b/CHANGELOG.md
index e2bc96e..2cd1bef 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- **`skills/ha-git-backup`** — an ops-companion skill for the engineer package: a two-circuit
+  Home Assistant backup system (real git in `/config` with a deploy key and a pre-commit secret
+  scanner + age-encrypted full backups in GitHub Releases), with install/sync/scan/offsite/restore
+  scripts, HA automations, a restore runbook and a mandatory monthly drill. Field-tested;
+  the secret scanner ships canary-tested (BusyBox `grep -e` lesson recorded).
+
 - **Manufacturer names from the archive itself** (`appprog_parser.py`): `parse_devices_from_project`
   now reads vendor names from the `knx_master.xml` shipped inside every `.knxproj`/`.knxprod`
   (e.g. M-0073 → HDL, M-00B6 → Ekinex S.p.A.) instead of relying on a hardcoded id map that can
diff --git a/README.md b/README.md
index 9a23196..21ab944 100644
--- a/README.md
+++ b/README.md
@@ -160,6 +160,9 @@ spec encodes.
   KNX IoT (Turtle/RDF) semantic export.
 - Live control of the house stays in the official Home Assistant integration (layer 1) — this
   server only prepares its configuration.
+- **Ops companion**: [`skills/ha-git-backup`](skills/ha-git-backup) — the life of your config
+  *after* deploy: a real git history of `/config` (deploy key + pre-commit secret scanner) plus
+  encrypted offsite backups in GitHub Releases, with a monthly restore drill.
 
 ### 🧩 The foundation — a growing device library
 
diff --git a/README.ru.md b/README.ru.md
index 12bf7dd..932d721 100644
--- a/README.ru.md
+++ b/README.ru.md
@@ -138,6 +138,9 @@ KNX Community в мае 2026 прямо просит такую интеграц
   семантический экспорт KNX IoT (Turtle/RDF).
 - Живое управление домом остаётся в официальной интеграции Home Assistant (слой 1) — этот сервер
   только готовит её конфигурацию.
+- **Ops-компаньон**: [`skills/ha-git-backup`](skills/ha-git-backup) — жизнь конфига *после*
+  деплоя: настоящая git-история `/config` (deploy key + pre-commit сканер секретов) плюс
+  шифрованные offsite-бэкапы в GitHub Releases и ежемесячный restore drill.
 
 ### 🧩 Фундамент — растущая библиотека устройств
 
diff --git a/skills/ha-git-backup/README.md b/skills/ha-git-backup/README.md
new file mode 100644
index 0000000..947a279
--- /dev/null
+++ b/skills/ha-git-backup/README.md
@@ -0,0 +1,37 @@
+# ha-git-backup — the ops companion skill
+
+Our Scenario 3 ends with `generate_ha_package` handing you a Home Assistant KNX YAML. This
+skill covers what happens **after you deploy it**: the life of your `/config`.
+
+**Two circuits, two different jobs:**
+
+1. **History** — a *real* git repo inside `/config`, pushed to a private GitHub repo over a
+   **deploy key** (blast radius: one repo). Every change is a meaningful commit
+   (`[daily] 3 file(s) | HA 2026.7.1`); a **pre-commit secret scanner** blocks any commit whose
+   diff contains a token, password or private key. Answers "what broke my automation last night"
+   in one `git diff`.
+2. **Recovery** — full native HA backups (including `.storage`: entity registry, auth, UI
+   dashboards) **age-encrypted** and uploaded to GitHub Releases with rotation. The private age
+   key never touches the HA host — a compromised host cannot read its own backups. Answers
+   "the SSD died" with a 30-minute restore.
+
+Plus: HA automations (daily commit at 03:30, a pre-update tag, a sync button, a failure alert),
+a health sensor, a restore runbook and a **mandatory monthly restore drill** — because a backup
+you have never restored is a hypothesis, not a backup.
+
+## Quick start
+
+```text
+1. Create an empty PRIVATE GitHub repo (e.g. ha-config).
+2. Follow references/setup.md: deploy key → scripts to /config/.git-sync/bin → install.sh.
+3. Add assets/configuration_snippet.yaml + assets/automations.yaml, restart HA (full restart).
+4. Circuit 2: age key + fine-grained PAT (Contents RW, ONE repo) → backup_offsite.sh.
+5. Run the first restore drill immediately (references/restore-runbook.md).
+```
+
+Start with [SKILL.md](SKILL.md) — it is written as a Claude skill (drop it into
+`.claude/skills/` and Claude will walk you through installation, incidents and drills), but it
+reads just as well as plain documentation for humans.
+
+> Field-tested: the secret scanner ships canary-tested (see LESSON-05 — a BusyBox grep quirk
+> silently disabled the private-key pattern until a planted-secret test caught it).
diff --git a/skills/ha-git-backup/SKILL.md b/skills/ha-git-backup/SKILL.md
new file mode 100644
index 0000000..4e0be2d
--- /dev/null
+++ b/skills/ha-git-backup/SKILL.md
@@ -0,0 +1,102 @@
+---
+name: ha-git-backup
+description: >-
+  Two-circuit backup & GitHub sync system for Home Assistant. Circuit 1 — real git inside
+  /config with a deploy key, a pre-commit secret scanner and meaningful commits; Circuit 2 —
+  full encrypted HA backups in GitHub Releases. Use EVERY time the task involves: backing up
+  Home Assistant, syncing its config, git in /config, restoring a config, rolling back a YAML
+  change, "what broke my automation", a leaked secret, setting up a deploy key, migrating HA
+  to new hardware, GitHub Releases for backups — and BEFORE any HA Core/OS update or AFTER any
+  incident with config loss. Also trigger on: backup, restore, gitleaks, secrets.yaml, 3-2-1.
+  The skill ships ready-made scripts (install, sync, secret-scan, offsite, restore) and a
+  mandatory protocol — do NOT reinvent sync logic, use scripts/.
+---
+
+# HA Git Backup — a two-circuit system
+
+Philosophy: **git gives you history, a backup gives you recovery. These are different jobs —
+different circuits solve them.** Projects like GithubConfigSync mix the two and implement git
+on top of the Contents API — we use real git.
+
+## Architecture
+
+```
+CIRCUIT 1: CONFIG HISTORY (what changed and when)
+/config (git repo) ──deploy key──▶ GitHub private repo (ha-config)
+  ├── triggers: daily 03:30 / pre-update / button / HA restart
+  ├── secret protection: .gitignore → pre-commit scan → age mirror
+  └── commit: "[trigger] N files | HA 2026.7.1" + file list
+
+CIRCUIT 2: RECOVERY (full state, including .storage)
+HA native backup (.tar) ──age──▶ GitHub Releases (ha-config)
+  ├── schedule: weekly + before updates
+  ├── rotation: 8 releases
+  └── restore drill: 1st of the month (mandatory)
+```
+
+The 3-2-1 rule: the config lives (1) on the HA host, (2) in the GitHub git repo, (3) as a full
+tarball in Releases — plus a local NAS copy if you have one.
+
+## IRON RULES
+
+1. **Deploy key, not a PAT.** Fine-grained WRITE access to ONE repository. A classic token with
+   the `repo` scope = access to all your private repos → forbidden.
+2. **A secret in the diff blocks the commit.** The pre-commit hook runs `secret_scan.sh`.
+   Bypassing with `--no-verify` — only deliberately, with the reason logged.
+3. **`.storage/` does NOT go to git** (auth, tokens), except the `lovelace*` whitelist —
+   dashboards. The full `.storage` lives only in the encrypted Circuit-2 tarball.
+4. **A backup without a restore drill is not a backup.** Monthly: download the release →
+   `age -d` → `tar -t` → verify `.storage/core.config_entries` is inside.
+5. **Do not rewrite the scripts from scratch.** The logic (lock, retry, notify, rotation) is
+   already in `scripts/` — read and use them.
+
+## Quick start (fresh install)
+
+1. Create an empty private repo `ha-config` on GitHub.
+2. Read `references/setup.md` — step by step: deploy key, install via the SSH add-on.
+3. Run `scripts/install.sh` inside HA — it does git init, .gitignore, hook, remote, first dry-run.
+4. Add the contents of `assets/configuration_snippet.yaml` to configuration.yaml and
+   `assets/automations.yaml` to your automations. **A full HA restart is required**
+   (`shell_command` and `command_line` are NOT loaded by a quick reload).
+5. Circuit 2: `scripts/backup_offsite.sh` needs a fine-grained PAT + an age key.
+   See `references/setup.md` §4.
+6. Run the first restore drill IMMEDIATELY — before the system is ever needed.
+
+## Symptom → action map
+
+| Symptom | Action |
+|---|---|
+| "Worked yesterday, broken today" | `git log --oneline -10`, `git diff HEAD~1` in /config — see what changed |
+| Broke YAML, HA won't start | `git checkout -- <file>` or `git reset --hard <good_sha>`, restart |
+| Secret leaked into the repo | `references/incident-secret-leak.md` — rotate the secret FIRST, history second |
+| Push silent/failing | `/config/.git-sync/log`; typical: read-only deploy key, stale known_hosts |
+| Migrating to new hardware | `scripts/restore.sh` — the Circuit-2 tarball, NOT the git repo (git has no .storage) |
+| Sync sensor = error | Check the log; the automation already sends a persistent_notification |
+| Repo bloated | Check binaries (db, tar) are gitignored; history is cleaned with `git gc` |
+
+## What's in the skill
+
+- `scripts/install.sh` — bootstrap the git repo in /config
+- `scripts/ha_git_sync.sh` — the sync engine: lock → scan → commit → push with retry → status file
+- `scripts/secret_scan.sh` — diff-based secret scanner (keys, tokens, private keys, passwords not via !secret)
+- `scripts/backup_offsite.sh` — Circuit 2: age encryption + upload to GitHub Releases + rotation
+- `scripts/restore.sh` — interactive restore with a checklist
+- `assets/gitignore.template`, `assets/configuration_snippet.yaml`, `assets/automations.yaml`
+- `references/setup.md` — full installation from scratch (deploy key, age, PAT)
+- `references/architecture.md` — design rationale, comparison with alternatives
+- `references/incident-secret-leak.md` — the secret-leak incident protocol
+- `references/restore-runbook.md` — restore runbook and the monthly drill
+
+## LESSONS (recorded — do not repeat)
+
+- **LESSON-01**: the GithubConfigSync approach (files one by one via the Contents API) = a commit
+  per file, rate limits, snapshot duplicates in the git repo. Real git solves all of that for free.
+- **LESSON-02**: .gitignore is NOT protection. A file added before the rule keeps being tracked.
+  Hence the mandatory pre-commit scan.
+- **LESSON-03**: a config git repo ≠ a backup: without .storage a restore gives you a bare HA
+  with no entity registry, no auth, no UI dashboards.
+- **LESSON-04**: a restore drill in calm times costs 10 minutes. A first-ever restore during an
+  outage without a drill costs an evening and your nerves.
+- **LESSON-05**: BusyBox grep treats patterns starting with `-` as options — always pass scan
+  patterns with `grep -E -e "$pattern"`. The scanner was silently skipping its private-key
+  pattern until this was caught by a canary test. Test your scanner with planted secrets.
diff --git a/skills/ha-git-backup/SKILL.ru.md b/skills/ha-git-backup/SKILL.ru.md
new file mode 100644
index 0000000..8a20d0f
--- /dev/null
+++ b/skills/ha-git-backup/SKILL.ru.md
@@ -0,0 +1,76 @@
+# HA Git Backup — двухконтурная система (русская версия; каноническая — [SKILL.md](SKILL.md))
+
+Философия: **git даёт историю, бэкап даёт восстановление. Это разные задачи — их решают разные
+контуры.** Проекты типа GithubConfigSync смешивают их и реализуют git поверх Contents API — мы
+используем настоящий git.
+
+## Архитектура
+
+```
+КОНТУР 1: ИСТОРИЯ КОНФИГА (что изменилось и когда)
+/config (git repo) ──deploy key──▶ GitHub private repo (ha-config)
+  ├── триггеры: daily 03:30 / pre-update / кнопка / рестарт HA
+  ├── защита секретов: .gitignore → pre-commit scan → age-зеркало
+  └── коммит: "[trigger] N files | HA 2026.7.1" + список файлов
+
+КОНТУР 2: ВОССТАНОВЛЕНИЕ (полное состояние, включая .storage)
+HA native backup (.tar) ──age──▶ GitHub Releases (ha-config)
+  ├── расписание: еженедельно + перед обновлениями
+  ├── ротация: 8 релизов
+  └── restore drill: 1-е число месяца (обязательный)
+```
+
+Правило 3-2-1: конфиг живёт (1) на хосте HA, (2) в git-репо GitHub, (3) полный тарбол в
+Releases + локальный NAS при наличии.
+
+## ЖЕЛЕЗНЫЕ ПРАВИЛА
+
+1. **Deploy key, не PAT.** Fine-grained доступ на ЗАПИСЬ в ОДИН репозиторий. Classic-токен со
+   scope `repo` = доступ ко всем приватным репо → запрещён.
+2. **Секрет в diff = коммит блокируется.** Pre-commit hook вызывает `secret_scan.sh`. Обход
+   через `--no-verify` — только осознанно и с записью причины в лог.
+3. **`.storage/` НЕ идёт в git** (auth, токены), кроме whitelist `lovelace*` — дашборды.
+   Полное `.storage` живёт только в шифрованном тарболе Контура 2.
+4. **Бэкап без restore drill — не бэкап.** Раз в месяц: скачать релиз → `age -d` → `tar -t` →
+   проверить наличие `.storage/core.config_entries`.
+5. **Не переписывать скрипты с нуля.** Логика (lock, retry, notify, ротация) уже в `scripts/`
+   — читать и использовать их.
+
+## Быстрый старт (новая установка)
+
+1. Создать приватный репо `ha-config` на GitHub (пустой).
+2. Прочитать `references/setup.md` — там пошагово: deploy key, установка через SSH add-on.
+3. Запустить `scripts/install.sh` внутри HA — он делает git init, .gitignore, hook, remote,
+   первый dry-run.
+4. Добавить `assets/configuration_snippet.yaml` в configuration.yaml и `assets/automations.yaml`
+   в автоматизации. **Нужен ПОЛНЫЙ перезапуск HA** (quick-reload не грузит
+   `shell_command`/`command_line`).
+5. Контур 2: `scripts/backup_offsite.sh` требует fine-grained PAT + age-ключ.
+   См. `references/setup.md` §4.
+6. Провести первый restore drill СРАЗУ — до того, как система понадобится.
+
+## Карта симптомов → действия
+
+| Симптом | Действие |
+|---|---|
+| «Вчера работало, сегодня нет» | `git log --oneline -10`, `git diff HEAD~1` в /config |
+| Сломал YAML, HA не стартует | `git checkout -- <file>` или `git reset --hard <good_sha>`, рестарт |
+| Утёк секрет в репо | `references/incident-secret-leak.md` — ротация секрета ПЕРВОЙ |
+| Push молчит/падает | `/config/.git-sync/log`; типовое: deploy key read-only, протух known_hosts |
+| Переезд на новое железо | `scripts/restore.sh` — тарбол Контура 2, НЕ git-репо (в git нет .storage) |
+| Sync-сенсор = error | Смотреть лог; автоматизация шлёт persistent_notification |
+| Репо распух | Бинарники (db, tar) в .gitignore; история чистится `git gc` |
+
+## УРОКИ (зафиксированы, не повторять)
+
+- **УРОК-01**: GithubConfigSync-подход (файлы по одному через Contents API) = коммит на файл,
+  rate limits, снапшоты-дубли. Настоящий git решает всё это бесплатно.
+- **УРОК-02**: .gitignore — НЕ защита. Файл, добавленный до правила, продолжает трекаться.
+  Отсюда обязательный pre-commit scan.
+- **УРОК-03**: git-репо конфига ≠ бэкап: без .storage восстановление даёт голый HA без entity
+  registry, авторизаций и дашбордов из UI.
+- **УРОК-04**: restore drill в спокойное время стоит 10 минут. Первое восстановление во время
+  аварии без drill стоит вечер и нервы.
+- **УРОК-05**: BusyBox-grep принимает паттерн, начинающийся с `-`, за опцию — паттерны сканера
+  передавать только как `grep -E -e "$pattern"`. Сканер молча пропускал проверку приватных
+  ключей, пока это не поймал тест с подсадной уткой. Проверяй сканер подсадными секретами.
diff --git a/skills/ha-git-backup/assets/automations.yaml b/skills/ha-git-backup/assets/automations.yaml
new file mode 100644
index 0000000..3aee0ab
--- /dev/null
+++ b/skills/ha-git-backup/assets/automations.yaml
@@ -0,0 +1,70 @@
+# ha-git-backup: automations. Add to automations.yaml or via the UI.
+
+- alias: "GitSync - daily commit"
+  triggers:
+    - trigger: time
+      at: "03:30:00"
+  actions:
+    - action: shell_command.git_sync_daily
+
+- alias: "GitSync - button"
+  triggers:
+    - trigger: state
+      entity_id: input_button.git_sync_now
+  actions:
+    - action: shell_command.git_sync_manual
+
+- alias: "GitSync - tag before a Core update"
+  triggers:
+    - trigger: state
+      entity_id: update.home_assistant_core_update
+      to: "on"
+  actions:
+    - action: shell_command.git_sync_pre_update
+
+- alias: "GitSync - commit after restart (capture the surviving state)"
+  triggers:
+    - trigger: homeassistant
+      event: start
+  actions:
+    - delay: "00:03:00"
+    - action: shell_command.git_sync_manual
+
+- alias: "GitSync - alert on failure"
+  triggers:
+    - trigger: state
+      entity_id: sensor.git_sync_status
+  conditions:
+    - condition: template
+      value_template: "{{ 'error' in states('sensor.git_sync_status') }}"
+  actions:
+    - action: persistent_notification.create
+      data:
+        title: "⚠️ Git Sync FAILED"
+        message: "{{ states('sensor.git_sync_status') }} — see /config/.git-sync/log"
+    # + add your notify.mobile_app_* here
+
+- alias: "Backup - weekly full + offsite"
+  triggers:
+    - trigger: time
+      at: "04:00:00"
+  conditions:
+    - condition: time
+      weekday: [sun]
+  actions:
+    - action: backup.create        # native HA backup (including .storage)
+    - delay: "00:10:00"
+    - action: shell_command.backup_offsite
+
+- alias: "Backup - restore drill reminder"
+  triggers:
+    - trigger: time
+      at: "10:00:00"
+  conditions:
+    - condition: template
+      value_template: "{{ now().day == 1 }}"
+  actions:
+    - action: persistent_notification.create
+      data:
+        title: "📋 Restore drill"
+        message: "1st of the month: verify recovery (restore.sh full, DRILL mode)."
diff --git a/skills/ha-git-backup/assets/configuration_snippet.yaml b/skills/ha-git-backup/assets/configuration_snippet.yaml
new file mode 100644
index 0000000..b17d73d
--- /dev/null
+++ b/skills/ha-git-backup/assets/configuration_snippet.yaml
@@ -0,0 +1,21 @@
+# ha-git-backup: add to configuration.yaml
+# Paths assume scripts live in /config/.git-sync/bin — adjust otherwise.
+# NOTE: shell_command and command_line load only on a FULL HA restart.
+
+shell_command:
+  git_sync_manual: "/config/.git-sync/bin/ha_git_sync.sh manual"
+  git_sync_daily: "/config/.git-sync/bin/ha_git_sync.sh daily"
+  git_sync_pre_update: "/config/.git-sync/bin/ha_git_sync.sh pre-update"
+  backup_offsite: "GH_REPO={{ 'YOUR_USER/ha-config' }} /config/.git-sync/bin/backup_offsite.sh"
+
+# Health sensor: reads the status file written by ha_git_sync.sh
+command_line:
+  - sensor:
+      name: git_sync_status
+      command: "cat /config/.git-sync/last_status 2>/dev/null || echo 'never'"
+      scan_interval: 300
+
+input_button:
+  git_sync_now:
+    name: "Git Sync Now"
+    icon: mdi:source-branch-sync
diff --git a/skills/ha-git-backup/assets/gitignore.template b/skills/ha-git-backup/assets/gitignore.template
new file mode 100644
index 0000000..e34cad6
--- /dev/null
+++ b/skills/ha-git-backup/assets/gitignore.template
@@ -0,0 +1,43 @@
+# ha-git-backup: echelon 1 of protection. Do NOT loosen without reading SKILL.md
+# --- secrets and state ---
+secrets.yaml
+*.pem
+*.key
+known_devices.yaml
+.storage/*
+!.storage/lovelace*
+.cloud/
+.google.token
+
+# --- databases and runtime junk (no place in git; Circuit 2 covers them) ---
+*.db
+*.db-*
+*.log
+*.log.*
+home-assistant.log*
+OZW_Log.txt
+deps/
+tts/
+image/
+www/community/
+__pycache__/
+.cache/
+.ha_run.lock
+
+# --- backups are not stored in the git repo ---
+backups/
+*.tar
+*.tar.age
+
+# --- embedded git repos keep their own history (content is covered by Circuit 2) ---
+esphome/
+
+# --- this system's own runtime files ---
+.git-sync/log
+.git-sync/last_status
+.git-sync/last_offsite
+.git-sync/gh_token
+.git-sync/age_recipient
+.git-sync/deploy_key
+.git-sync/deploy_key.pub
+.HA_VERSION
diff --git a/skills/ha-git-backup/references/architecture.md b/skills/ha-git-backup/references/architecture.md
new file mode 100644
index 0000000..1dc8b9f
--- /dev/null
+++ b/skills/ha-git-backup/references/architecture.md
@@ -0,0 +1,41 @@
+# Architecture: design rationale
+
+## Why two circuits, not one
+Git answers "what changed and when" (diffs, blame, file rollback in seconds). A backup answers
+"how do I bring the system up from nothing" (.storage: entity registry, auth, config entries,
+the zigbee network). Mixing the two jobs produces a system that does both badly — the main
+lesson from analysing GithubConfigSync.
+
+## Comparison with alternatives
+| Solution | History | Full recovery | Secrets | Verdict |
+|---|---|---|---|---|
+| **This system** | real git | Releases + age | 3 echelons | ✅ |
+| GithubConfigSync | pseudo-git (Contents API, commit per file) | no (.storage excluded) | .gitignore only | history — yes, restore — no |
+| Git Pull add-on (official) | pull only | no | — | a different job (deploy) |
+| Google Drive Backup add-on | no | yes | HA encryption | great as an ADDITION to Circuit 2 (second offsite copy = full 3-2-1) |
+| Bare cron+git | yes | no | manual | that IS Circuit 1, but without scan/notify/lock |
+
+## Key decisions
+1. **Deploy key instead of a PAT for git** — blast radius of one repo.
+2. **Fine-grained PAT only for the Releases API** (Contents RW, one repo) — Releases can't be
+   pushed over SSH.
+3. **The pre-commit scan is mandatory**: .gitignore does not protect against a secret written
+   INTO automations.yaml as a literal (a real, frequent case: a Telegram bot token in a
+   rest_command).
+4. **Whitelist `.storage/lovelace*`**: dashboards created in the UI live in .storage — without
+   them the config history is incomplete. The rest of .storage holds auth → encrypted Circuit 2
+   only.
+5. **age, not GPG**: a single binary, no keyring state, the key is one line. There is NO private
+   key on the HA host — a compromised host ≠ readable backups.
+6. **GitHub Releases, not git-lfs and not files in the repo**: binaries in git bloat history
+   forever; Releases is flat storage with a 2 GB/file limit and trivial rotation.
+7. **A status file + command_line sensor, not push notifications from the script**: the script
+   does not depend on HA API tokens; observability is done by HA itself.
+8. **Locking via flock**: an HA restart plus the daily trigger cannot race.
+
+## System boundaries (deliberate)
+- The 2 GB Releases limit: exclude media/large DBs from the native backup (partial backup).
+- The git repo in /config is visible to every add-on with config access — threat model:
+  trusted add-ons.
+- Git history keeps deleted files forever: a leaked secret requires the
+  incident-secret-leak.md protocol, not a simple delete.
diff --git a/skills/ha-git-backup/references/incident-secret-leak.md b/skills/ha-git-backup/references/incident-secret-leak.md
new file mode 100644
index 0000000..68f815b
--- /dev/null
+++ b/skills/ha-git-backup/references/incident-secret-leak.md
@@ -0,0 +1,32 @@
+# Incident: a secret landed in the git repo
+
+The order is STRICT. Step 1 comes before everything else.
+
+## 1. ROTATE THE SECRET (immediately)
+A leaked token/password/key counts as compromised from the moment of push, even in a private
+repo. Revoke and reissue it at the provider (GitHub token → revoke; a service API key →
+regenerate; a password → change). Only then move on to cleanup.
+
+## 2. Assess the exposure
+- `git log --all -S '<secret fragment>' --oneline` — which commits carry it.
+- Is the repo private? Any forks/clones? Who had access?
+
+## 3. Rewrite history
+```bash
+# on your workstation, not on HA:
+git clone git@github.com:YOUR_USER/ha-config.git && cd ha-config
+pip install git-filter-repo
+git filter-repo --replace-text <(echo '<secret>==>REDACTED')
+git push --force --all && git push --force --tags
+```
+On HA afterwards: `cd /config && git fetch && git reset --hard origin/main`.
+
+## 4. GitHub specifics
+A force-push does NOT delete objects instantly: commits stay reachable by SHA via cache/API.
+For a full purge — GitHub Support (a request to delete unreachable objects). One more reason
+step 1 is primary: history may never be fully scrubbed; rotation closes the risk with certainty.
+
+## 5. Close the gap
+- Why didn't the scan catch it? → add the pattern to `secret_scan.sh` PATTERNS.
+- The value should have lived in secrets.yaml behind `!secret` — move it.
+- Record a LESSON in SKILL.md.
diff --git a/skills/ha-git-backup/references/restore-runbook.md b/skills/ha-git-backup/references/restore-runbook.md
new file mode 100644
index 0000000..211540e
--- /dev/null
+++ b/skills/ha-git-backup/references/restore-runbook.md
@@ -0,0 +1,38 @@
+# Restore runbook
+
+## Scenario A: a broken file/config (frequent) — Circuit 1
+```bash
+cd /config
+git log --oneline -10                 # find the last known-good commit
+git diff <sha> --stat                 # what changed
+git checkout <sha> -- automations.yaml   # surgical rollback
+ha core check && ha core restart
+```
+Time: minutes. If HA won't start at all — same commands via the SSH add-on (it lives
+independently of Core).
+
+## Scenario B: dead SD/SSD/hardware — Circuit 2
+1. Fresh HA OS install on the new medium.
+2. On your workstation: download the latest `backup/*` release from `ha-config`, decrypt:
+   `age -d -i age_key.txt -o restored.tar ha-backup-*.tar.age`
+3. New HA onboarding → "Restore from backup" → upload restored.tar.
+4. After start verify: entity registry intact, auth alive, dashboards present, ESPHome nodes
+   reconnected, zigbee/z-wave network up.
+5. Verify Circuit 1: `cd /config && git status` (the repo arrives inside the backup, .git and all).
+
+## Scenario C: need a year-old config
+Circuit 1: `git log --before="2025-07-01" -1` → checkout the needed file from that SHA.
+
+## The monthly DRILL (1st of the month, reminder ships in automations.yaml)
+The goal — prove the "Releases → age → tar" chain is alive WITHOUT a real restore:
+1. Download the latest release.
+2. `age -d` with the private key (this doubles as "the key isn't lost" check!).
+3. `tar -tf restored.tar | grep -c .` — the archive reads.
+4. `tar -tf restored.tar | grep core.config_entries` — .storage is inside.
+5. `date +%F > /config/.git-sync/last_drill`
+Any step failing = an incident: fix now, not when the SSD burns.
+
+## System health metrics
+- `sensor.git_sync_status` = ok, age < 26 h
+- `.git-sync/last_offsite` — age < 8 days
+- `.git-sync/last_drill` — age < 35 days
diff --git a/skills/ha-git-backup/references/setup.md b/skills/ha-git-backup/references/setup.md
new file mode 100644
index 0000000..fc33a91
--- /dev/null
+++ b/skills/ha-git-backup/references/setup.md
@@ -0,0 +1,61 @@
+# Installation from scratch
+
+## §1. Prerequisites
+- HA OS / Supervised with the **Advanced SSH & Web Terminal** add-on (it ships git and ssh).
+- A private repo `ha-config` on GitHub (empty, no README).
+- Copy the skill's scripts to `/config/.git-sync/bin/` and the gitignore template to
+  `/config/.git-sync/assets/`, then `chmod +x` the scripts.
+- Note: with `sftp: false` in the add-on config, `scp` won't work — use a tar pipe:
+  `tar cz scripts | ssh <your-ha-host> 'cd /tmp && tar xz'`.
+
+## §2. Deploy key (Circuit 1) — NOT a PAT
+```bash
+ssh-keygen -t ed25519 -f /config/.git-sync/deploy_key -N "" -C "ha-git-backup"
+cat /config/.git-sync/deploy_key.pub
+```
+GitHub → repo `ha-config` → Settings → Deploy keys → Add key → **Allow write access**.
+
+SSH config so git picks exactly this key:
+```bash
+mkdir -p ~/.ssh && cat >> ~/.ssh/config <<'EOF'
+Host github.com
+  IdentityFile /config/.git-sync/deploy_key
+  IdentitiesOnly yes
+EOF
+```
+Why a deploy key: it grants access to ONE repo. A compromised key ≠ a compromised GitHub
+account (unlike a classic PAT with the `repo` scope).
+
+## §3. Circuit 1: install
+```bash
+/config/.git-sync/bin/install.sh git@github.com:YOUR_USER/ha-config.git
+# review the dry-run file list for secrets, then:
+/config/.git-sync/bin/ha_git_sync.sh manual
+```
+Add `assets/configuration_snippet.yaml` and `assets/automations.yaml`, **fully restart HA**
+(quick reload does not load `shell_command`/`command_line`), check `sensor.git_sync_status`.
+
+## §4. Circuit 2: offsite to GitHub Releases
+1. **age key** (generate NOT on HA but on your workstation):
+   `age-keygen -o age_key.txt` → store the private key offline (password manager / paper).
+   Only the public half goes to HA:
+   `echo "age1..." > /config/.git-sync/age_recipient`
+2. **Fine-grained PAT**: GitHub → Settings → Developer settings → Fine-grained tokens →
+   access to `ha-config` only, permission **Contents: Read and write**. 1-year expiry,
+   calendar reminder to rotate.
+   `echo "github_pat_..." > /config/.git-sync/gh_token && chmod 600 /config/.git-sync/gh_token`
+3. `age` inside the SSH add-on container: add `age` to the add-on's `packages:` list (persists
+   across restarts) or `apk add age`.
+4. Test: `GH_REPO=YOUR_USER/ha-config /config/.git-sync/bin/backup_offsite.sh`
+
+## §5. Optional: an age mirror of secrets.yaml (echelon 3)
+To make the git repo self-sufficient for restoring the YAML part:
+```bash
+age -r "$(cat /config/.git-sync/age_recipient)" -o /config/secrets.yaml.age /config/secrets.yaml
+```
+`secrets.yaml.age` is NOT gitignored → it goes to git. Add the command to ha_git_sync.sh before
+`git add` if you enable this. Decryption requires only the private key, which is not on HA.
+
+## §6. Final — the mandatory first drill
+Right after installation run `restore.sh full` in DRILL mode (steps 1–4). Record the date in
+`/config/.git-sync/last_drill`.
diff --git a/skills/ha-git-backup/scripts/backup_offsite.sh b/skills/ha-git-backup/scripts/backup_offsite.sh
new file mode 100755
index 0000000..f91e376
--- /dev/null
+++ b/skills/ha-git-backup/scripts/backup_offsite.sh
@@ -0,0 +1,56 @@
+#!/usr/bin/env bash
+# backup_offsite.sh — Circuit 2: freshest native HA backup → age encryption →
+# GitHub Release in the ha-config repo. Rotation: keep the KEEP latest releases.
+# Requires: age, curl, a fine-grained PAT (Contents RW of ONE repo) in
+# /config/.git-sync/gh_token, the public age key in /config/.git-sync/age_recipient
+set -euo pipefail
+
+CONFIG_DIR="${CONFIG_DIR:-/config}"
+BACKUP_DIR="${BACKUP_DIR:-/backup}"          # native backup path on supervised/HAOS
+REPO="${GH_REPO:?export GH_REPO=user/ha-config}"
+KEEP="${KEEP:-8}"
+TOKEN="$(cat "$CONFIG_DIR/.git-sync/gh_token")"
+RECIPIENT="$(cat "$CONFIG_DIR/.git-sync/age_recipient")"
+API="https://api.github.com/repos/$REPO"
+AUTH=(-H "Authorization: Bearer $TOKEN" -H "Accept: application/vnd.github+json")
+LOG="$CONFIG_DIR/.git-sync/log"
+log(){ echo "$(date '+%F %T') [offsite] $*" >> "$LOG"; }
+
+# 1. The freshest native backup (creating it is the HA automation's job, before this call)
+LATEST="$(ls -t "$BACKUP_DIR"/*.tar 2>/dev/null | head -1)"
+[ -n "$LATEST" ] || { log "FAIL: no .tar in $BACKUP_DIR"; exit 1; }
+
+# 2. Encrypt (the HA tarball may already be password-encrypted — age on top is fine)
+STAMP="$(date +%Y-%m-%d_%H%M)"
+ENC="/tmp/ha-backup-$STAMP.tar.age"
+age -r "$RECIPIENT" -o "$ENC" "$LATEST"
+SIZE=$(du -m "$ENC" | cut -f1)
+[ "$SIZE" -lt 1900 ] || { log "FAIL: $SIZE MB > GitHub Releases limit (2GB) — exclude media from the backup"; rm -f "$ENC"; exit 1; }
+
+# 3. Create the release
+TAG="backup/$STAMP"
+REL_JSON="$(curl -sf "${AUTH[@]}" -X POST "$API/releases" \
+  -d "{\"tag_name\":\"$TAG\",\"name\":\"HA backup $STAMP\",\"body\":\"age-encrypted, $SIZE MB\"}")"
+REL_ID="$(echo "$REL_JSON" | grep -o '"id": *[0-9]*' | head -1 | grep -o '[0-9]*')"
+[ -n "$REL_ID" ] || { log "FAIL: release create"; rm -f "$ENC"; exit 1; }
+
+# 4. Upload the asset
+curl -sf "${AUTH[@]}" -H "Content-Type: application/octet-stream" \
+  --data-binary @"$ENC" \
+  "https://uploads.github.com/repos/$REPO/releases/$REL_ID/assets?name=$(basename "$ENC")" >/dev/null \
+  || { log "FAIL: asset upload"; rm -f "$ENC"; exit 1; }
+rm -f "$ENC"
+log "OK: $TAG uploaded ($SIZE MB)"
+
+# 5. Rotation: delete backup/* releases beyond KEEP (and their tags)
+curl -sf "${AUTH[@]}" "$API/releases?per_page=100" \
+ | grep -oE '"tag_name": *"backup/[^"]*"|"id": *[0-9]*' \
+ | paste - - | grep 'backup/' | sort -r | tail -n +$((KEEP+1)) \
+ | while read -r idline tagline; do
+     RID="$(echo "$idline" | grep -o '[0-9]*')"
+     RTAG="$(echo "$tagline" | sed 's/.*"backup/backup/;s/"//g')"
+     curl -sf "${AUTH[@]}" -X DELETE "$API/releases/$RID" >/dev/null || true
+     curl -sf "${AUTH[@]}" -X DELETE "$API/git/refs/tags/$RTAG" >/dev/null || true
+     log "rotated out: $RTAG"
+   done
+echo "ok: offsite $TAG" > "$CONFIG_DIR/.git-sync/last_offsite"
diff --git a/skills/ha-git-backup/scripts/ha_git_sync.sh b/skills/ha-git-backup/scripts/ha_git_sync.sh
new file mode 100755
index 0000000..bf880f9
--- /dev/null
+++ b/skills/ha-git-backup/scripts/ha_git_sync.sh
@@ -0,0 +1,65 @@
+#!/usr/bin/env bash
+# ha_git_sync.sh — Circuit 1: git sync /config → GitHub
+# Usage: ha_git_sync.sh [trigger]   trigger: manual|daily|pre-update|restart
+# Exit: 0 = ok/nothing-to-do, 1 = error (recorded in the status file)
+set -uo pipefail
+
+CONFIG_DIR="${CONFIG_DIR:-/config}"
+SYNC_DIR="$CONFIG_DIR/.git-sync"
+LOG="$SYNC_DIR/log"
+STATUS="$SYNC_DIR/last_status"      # read by the HA command_line sensor
+LOCKFILE="/tmp/ha_git_sync.lock"
+TRIGGER="${1:-manual}"
+BRANCH="${GIT_BRANCH:-main}"
+RETRIES=3
+
+mkdir -p "$SYNC_DIR"
+log() { echo "$(date '+%F %T') [$TRIGGER] $*" >> "$LOG"; }
+fail() { echo "error: $*" > "$STATUS"; log "FAIL: $*"; exit 1; }
+ok()   { echo "ok: $*"    > "$STATUS"; log "OK: $*";   exit 0; }
+
+# --- lock: no parallel runs ---------------------------------------------------
+exec 9>"$LOCKFILE"
+flock -n 9 || fail "another sync is running"
+
+cd "$CONFIG_DIR" || fail "no $CONFIG_DIR"
+[ -d .git ] || fail "not a git repo — run install.sh first"
+
+# --- any changes? --------------------------------------------------------------
+git add -A
+if git diff --cached --quiet; then
+  ok "clean, nothing to commit"
+fi
+
+# --- secret scanner (echelon 2) -----------------------------------------------
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+if ! "$SCRIPT_DIR/secret_scan.sh"; then
+  git reset -q  # unstage everything, commit nothing
+  fail "SECRET DETECTED in staged diff — commit blocked, see $LOG"
+fi
+
+# --- a meaningful commit --------------------------------------------------------
+HA_VER="unknown"
+[ -f .HA_VERSION ] && HA_VER="$(cat .HA_VERSION)"
+NFILES=$(git diff --cached --name-only | wc -l | tr -d ' ')
+SUMMARY="[$TRIGGER] $NFILES file(s) | HA $HA_VER"
+BODY="$(git diff --cached --stat | tail -20)"
+
+git commit -q -m "$SUMMARY" -m "$BODY" || fail "commit failed"
+log "committed: $SUMMARY"
+
+# --- tag before an update -------------------------------------------------------
+if [ "$TRIGGER" = "pre-update" ]; then
+  TAG="pre-update/$(date +%Y-%m-%d_%H%M)"
+  git tag -f "$TAG" && log "tagged $TAG"
+fi
+
+# --- push with retry and exponential backoff ------------------------------------
+n=0
+until git push -q origin "$BRANCH" --tags 2>>"$LOG"; do
+  n=$((n+1))
+  [ $n -ge $RETRIES ] && fail "push failed after $RETRIES attempts (commit is local, next run will push it)"
+  sleep $((5 * 2 ** n))
+done
+
+ok "$SUMMARY pushed"
diff --git a/skills/ha-git-backup/scripts/install.sh b/skills/ha-git-backup/scripts/install.sh
new file mode 100755
index 0000000..d2df300
--- /dev/null
+++ b/skills/ha-git-backup/scripts/install.sh
@@ -0,0 +1,57 @@
+#!/usr/bin/env bash
+# install.sh — Circuit 1 bootstrap: a git repo in /config.
+# Run ONCE from the SSH add-on. Requires: git, ssh, a created private repo and
+# a deploy key (see references/setup.md §2). Idempotent.
+set -euo pipefail
+
+CONFIG_DIR="${CONFIG_DIR:-/config}"
+REMOTE="${1:-}"   # git@github.com:YOUR_USER/ha-config.git
+BRANCH="${GIT_BRANCH:-main}"
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+
+[ -n "$REMOTE" ] || { echo "Usage: install.sh git@github.com:YOUR_USER/ha-config.git"; exit 1; }
+command -v git >/dev/null || { echo "git not found — use the Advanced SSH & Web Terminal add-on"; exit 1; }
+
+cd "$CONFIG_DIR"
+mkdir -p .git-sync
+
+# 1. The repository
+if [ ! -d .git ]; then
+  git init -q -b "$BRANCH"
+  echo "[+] git init ($BRANCH)"
+fi
+git config user.name  "ha-git-backup"
+git config user.email "ha-git-backup@config.local"
+git remote get-url origin >/dev/null 2>&1 && git remote set-url origin "$REMOTE" || git remote add origin "$REMOTE"
+
+# 2. .gitignore (echelon 1) — never overwrite an existing one
+if [ ! -f .gitignore ]; then
+  cp "$SCRIPT_DIR/../assets/gitignore.template" .gitignore
+  echo "[+] .gitignore installed"
+else
+  echo "[i] .gitignore already exists — diff it against assets/gitignore.template manually"
+fi
+
+# 3. pre-commit hook (echelon 2)
+mkdir -p .git/hooks
+cat > .git/hooks/pre-commit <<EOF
+#!/usr/bin/env bash
+exec "$SCRIPT_DIR/secret_scan.sh"
+EOF
+chmod +x .git/hooks/pre-commit .git-sync 2>/dev/null || true
+chmod +x "$SCRIPT_DIR"/*.sh
+echo "[+] pre-commit secret scan wired up"
+
+# 4. SSH access check (deploy key)
+if ssh -o BatchMode=yes -o StrictHostKeyChecking=accept-new -T git@github.com 2>&1 | grep -q "successfully authenticated"; then
+  echo "[+] deploy key works"
+else
+  echo "[!] SSH to GitHub failed — check the deploy key (references/setup.md §2)"
+fi
+
+# 5. First pass: show WHAT would enter the repo, before any real commit
+echo "[i] DRY-RUN — these files would land in the first commit:"
+git add -A -n | head -50
+echo "..."
+echo "Review the list above for secrets. If it looks right, run:"
+echo "  $SCRIPT_DIR/ha_git_sync.sh manual"
diff --git a/skills/ha-git-backup/scripts/restore.sh b/skills/ha-git-backup/scripts/restore.sh
new file mode 100755
index 0000000..214885d
--- /dev/null
+++ b/skills/ha-git-backup/scripts/restore.sh
@@ -0,0 +1,35 @@
+#!/usr/bin/env bash
+# restore.sh — recovery. Two scenarios:
+#   restore.sh file   — roll back files from git (Circuit 1)
+#   restore.sh full   — full restore from a GitHub Release (Circuit 2)
+# Also used for the monthly restore drill (references/restore-runbook.md)
+set -euo pipefail
+MODE="${1:-help}"
+
+case "$MODE" in
+file)
+  cd "${CONFIG_DIR:-/config}"
+  echo "Recent commits:"; git log --oneline -15
+  echo
+  echo "Roll back one file:    git checkout <sha> -- <file>"
+  echo "Roll back everything:  git reset --hard <sha>   (DESTRUCTIVE: wipes uncommitted changes)"
+  echo "What changed:          git diff <sha> --stat"
+  echo "After rollback: validate the config (ha core check) and restart HA."
+  ;;
+full)
+  REPO="${GH_REPO:?export GH_REPO=user/ha-config}"
+  KEYFILE="${AGE_KEY:?export AGE_KEY=/path/to/age_key.txt}"
+  echo "=== FULL RESTORE (Circuit 2) ==="
+  echo "1. List backups:   gh release list -R $REPO   (or the /releases API)"
+  echo "2. Download asset: gh release download <backup/TAG> -R $REPO -D /tmp"
+  echo "3. Decrypt:        age -d -i $KEYFILE -o restored.tar /tmp/ha-backup-*.tar.age"
+  echo "4. Verify:         tar -tf restored.tar | grep -c . && tar -tf restored.tar | grep core.config_entries"
+  echo "5. HAOS: place restored.tar in /backup and restore via the UI"
+  echo "   (Settings → System → Backups), or onboarding-restore on a fresh install."
+  echo "6. After start: verify entity registry, auth, dashboards, ESPHome nodes."
+  echo
+  echo "DRILL mode: run steps 1-4 WITHOUT step 5, record the date in .git-sync/last_drill"
+  ;;
+*)
+  echo "Usage: restore.sh file|full"; exit 1;;
+esac
diff --git a/skills/ha-git-backup/scripts/secret_scan.sh b/skills/ha-git-backup/scripts/secret_scan.sh
new file mode 100755
index 0000000..8410f5a
--- /dev/null
+++ b/skills/ha-git-backup/scripts/secret_scan.sh
@@ -0,0 +1,56 @@
+#!/usr/bin/env bash
+# secret_scan.sh — echelon 2 of protection: scans the STAGED diff for secrets.
+# Exit: 0 = clean, 1 = secret found (the commit must be blocked).
+# Also installed as the pre-commit hook (install.sh wires it up).
+set -uo pipefail
+
+CONFIG_DIR="${CONFIG_DIR:-/config}"
+LOG="$CONFIG_DIR/.git-sync/log"
+ALLOWLIST="$CONFIG_DIR/.git-sync/scan_allowlist"   # exclusion lines (one per line)
+
+# Only ADDED diff lines, without headers
+DIFF="$(git diff --cached --unified=0 | grep -E '^\+' | grep -vE '^\+\+\+' || true)"
+[ -z "$DIFF" ] && exit 0
+
+# Apply the allowlist (false positives are recorded THERE, not by disabling the scanner)
+if [ -f "$ALLOWLIST" ]; then
+  while IFS= read -r line; do
+    [ -n "$line" ] && DIFF="$(echo "$DIFF" | grep -vF "$line" || true)"
+  done < "$ALLOWLIST"
+fi
+
+PATTERNS=(
+  # private keys
+  '-----BEGIN (RSA |EC |OPENSSH |DSA |PGP )?PRIVATE KEY'
+  # cloud / API tokens of known formats
+  'AKIA[0-9A-Z]{16}'                    # AWS access key
+  'ghp_[A-Za-z0-9]{36}'                 # GitHub classic PAT
+  'github_pat_[A-Za-z0-9_]{22,}'        # GitHub fine-grained PAT
+  'xox[baprs]-[A-Za-z0-9-]{10,}'        # Slack
+  'AIza[0-9A-Za-z_-]{35}'               # Google API key
+  'sk-[A-Za-z0-9_-]{20,}'               # OpenAI/Anthropic-style
+  'eyJhbGciOi[A-Za-z0-9_-]{20,}'        # JWT / HA long-lived token
+  # a secret-looking field assigned a literal value NOT via !secret
+  '(password|api_key|token|client_secret|bearer)["'"'"']?\s*[:=]\s*["'"'"']?[A-Za-z0-9_\-\.\+/=]{8,}'
+)
+
+HIT=""
+for p in "${PATTERNS[@]}"; do
+  # NOTE: "-e" is mandatory — BusyBox grep treats a pattern starting with "-" as an
+  # option and silently skips it otherwise (LESSON-05, caught by a canary test).
+  M="$(echo "$DIFF" | grep -inE -e "$p" | grep -viE '!secret|REDACTED|example|changeme|password_here' || true)"
+  [ -n "$M" ] && HIT="$HIT
+[$p]
+$M"
+done
+
+if [ -n "$HIT" ]; then
+  {
+    echo "$(date '+%F %T') SECRET-SCAN BLOCKED COMMIT:"
+    echo "$HIT" | head -40
+    echo "--- False positive? Add the exact line to $ALLOWLIST"
+  } >> "$LOG" 2>/dev/null || true
+  echo "SECRET DETECTED — commit blocked. Details: $LOG" >&2
+  exit 1
+fi
+exit 0