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+# Ubongo Physical Build — Implementation Plan
+
+> **For agentic workers:** Execute task-by-task. This is the **physical bring-up** of
+> `ubongo`. The 2026-06-05 plan (`2026-06-05-ubongo-control-host.md`) was
+> *documentation-only* (it authored ADR-015); this is its sequel — taking the actual
+> box from bare Debian 13 to a working control / AI-worker node.
+
+**Goal:** Bring the Lenovo ThinkCentre M70q from a fresh Debian 13 install to a working
+control node: toolchain, dedicated `claude` identity, repo + Claude Code, vault access,
+inventory wiring, keys-only SSH, and reconciliation of the docs to "built."
+
+**Spec / decisions of record:** ADR-015 + `docs/superpowers/specs/2026-06-05-ubongo-control-host-design.md`,
+plus the interactive build decisions captured below (2026-06-11 session).
+
+---
+
+## Decisions made this session (2026-06-11)
+
+- **Hardware:** Lenovo ThinkCentre M70q Tiny · i3-10100T (4c/8t) · 16 GB · 256 GB
+  SanDisk X600 SATA SSD (TCG **Opal**-capable; Opal **unused**, see encryption).
+- **BIOS:** auto-power-on after loss; Wake-on-LAN on; ErP/deep-S5 off; **supervisor
+  password set**; external/USB + PXE boot **disabled**; Secure Boot on; TPM (PTT) on;
+  VT-x/VT-d on; Better-Thermal cooling.
+- **Disk encryption: NONE.** Accepted risk — compensated by physical security + BIOS
+  supervisor password + disabled external boot. Recorded in `accepted-risks.md` (Task H1).
+- **Partitioning:** simple single ext4 root (`/dev/sda2`, 221 G) + 12 G swap, no LVM.
+  Revisit via reinstall onto LVM/bigger drive only if the layout bites.
+- **Identity:** dedicated **`claude`** user — for **attribution + revocation, not
+  containment**. In the `docker` group (Molecule); **no local sudo** (boma deploys run
+  over SSH as `ansible`; the agent needs Docker, not root). Reached via `sudo -iu claude`
+  from `sjat`. Own `ed25519` key for Forgejo. ADR-021 leaves this identity open — note it.
+- **Access:** LAN SSH only for now — the NetBird mesh (ADR-016) is deferred (`askari` +
+  service machinery unbuilt). Keys-only enforced after bootstrap.
+- **Address:** `10.20.10.151/24` on `eno1`. Make stable via an OPNsense DHCP reservation.
+
+**Pinned versions (match `fisi`):** docker 29.5.2 · rbw 1.15.0 · node 20.19.2 ·
+claude 2.1.173. Terraform is absent on `fisi` (TF un-init'd) — install deferred.
+
+---
+
+## Pre-flight
+
+- **Temp passwordless sudo** for `sjat` during the build (`/etc/sudoers.d/99-boma-build`);
+  **removed in Task F2**. Without it, non-interactive SSH `sudo` hangs.
+- **`rbw unlock`** on `fisi` before any commit (pre-commit decrypts `vault.yml`).
+- **Commit style:** one commit per logical unit; imperative subject ≤72 chars; trailer
+  `Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>`.
+- Drive the live box (`ubongo`) directly over SSH; do repo/doc tasks (H) as clean commits.
+
+---
+
+## Stage A — Toolchain (on `ubongo`, via `sjat` sudo)
+
+- [ ] **A1.** apt base: `git make build-essential python3-venv python3-pip curl
+  ca-certificates gnupg jq` (+ `apt update`).
+- [ ] **A2.** Docker Engine from Docker's official apt repo (Debian 13/trixie); enable +
+  start; confirm `docker --version` ≈ 29.5.2.
+- [ ] **A3.** `rbw` 1.15.0 — try `apt install rbw`; if the version doesn't match, install
+  the pinned release binary to `/usr/local/bin` (match `fisi`).
+- [ ] **A4.** Node 20.19.2 (nodesource or distro) — only if Claude Code needs it; the
+  native installer bundles its runtime, so Node may be optional.
+- [ ] **A5.** Claude Code via the **native installer** (matches `fisi`'s
+  `~/.local/share/claude/versions/`), installed under the `claude` user in Stage C.
+- [ ] Defer Terraform (absent on `fisi`).
+
+## Stage B — Identity (`claude` user)
+
+- [ ] **B1.** `useradd -m -s /bin/bash claude`; lock the password (`passwd -l claude`) —
+  reached only via `sudo -iu claude` from `sjat` or its own key.
+- [ ] **B2.** Add `claude` to the `docker` group.
+- [ ] **B3.** No sudo for `claude` (explicit decision). Confirm `sudo -iu claude` works.
+
+## Stage C — Repo + Claude Code (as `claude`)
+
+- [ ] **C1.** Generate `claude`'s `ed25519` key; **[USER]** register the public key in
+  Forgejo (Settings → SSH keys).
+- [ ] **C2.** Clone `ssh://git@forgejo.nyumbani.baobab.band:7577/sjat/boma.git` into
+  `/home/claude/Projects/boma`.
+- [ ] **C3.** `make setup` (venv + `requirements.txt`); `make collections`.
+- [ ] **C4.** Install Claude Code (native installer) for `claude`; set up plugins/MCP/
+  settings per `docs/runbooks/claude-code-setup.md`. Set git `user.name`/`user.email`.
+
+## Stage D — Vault (`rbw`)
+
+- [ ] **D1.** `rbw config set base_url https://vaultwarden.baobab.band`; set email.
+- [ ] **D2. [USER]** `rbw login` (master password) on `ubongo`; then `rbw sync`,
+  `rbw unlock`; verify `rbw get boma-ansible-vault` returns the vault password.
+- [ ] **D3.** **Offline-cache verification (ADR-015 open item, security-relevant):**
+  confirm `rbw` decrypts its local cache with Vaultwarden unreachable. Stamp the result
+  into ADR-015 / `rotate-secrets.md` (replaces the `TO VERIFY` note).
+
+## Stage E — Inventory + base (partial)
+
+- [ ] **E1.** Add `ubongo` to `inventories/production/hosts.yml` under `control`
+  (manual exception; note `tf-inventory` will overwrite — re-add after).
+- [ ] **E2.** Set `base__firewall_control_addr` to `10.20.10.151` in the appropriate
+  `group_vars` (the dormant `ssh-from-control` knob, ADR-020/021).
+- [ ] **E3.** `make check PLAYBOOK=site` against `control`; apply the built `firewall`
+  concern only (SSH-hardening/fail2ban/auditd concerns are unbuilt — note the gap).
+
+## Stage F — Hardening / address
+
+- [ ] **F1.** Disable SSH password auth (keys-only) via `/etc/ssh/sshd_config.d/`;
+  `PermitRootLogin no`; reload `sshd` (we're on a key, so safe).
+- [ ] **F2.** **Remove the temp NOPASSWD** drop-in (`/etc/sudoers.d/99-boma-build`).
+- [ ] **F3. [USER]** OPNsense DHCP reservation for `10.20.10.151`.
+
+## Stage H — Docs reconciliation (repo commits)
+
+- [ ] **H1.** `accepted-risks.md`: add the plaintext-disk accepted risk (compensations:
+  physical security, BIOS supervisor password, no external boot).
+- [ ] **H2.** `docs/hardware/reference.md`: fill `ubongo`'s real specs (M70q, i3-10100T,
+  16 GB, 256 GB SanDisk X600) into the TBD skeleton; node-capacity row already present.
+- [ ] **H3.** `STATUS.md`: move `ubongo` from "Designed but not built" toward built
+  (note what's live vs. still pending — mesh, full `base`).
+- [ ] **H4.** Note the dedicated-`claude` identity decision (short amendment to ADR-021
+  or ADR-015) and the LAN address.
+
+---
+
+## Out of scope this session
+
+- **Mesh VPN** (NetBird) — needs `askari` + service roles (ADR-016). SSH stays LAN-only.
+- **Full `base` hardening** — SSH/fail2ban/auditd concerns not built (only `firewall`).
+- **Recovery wiring (G)** — TF-state backup to `mamba`, rbw mirror — no TF state yet
+  (TF un-init'd). `mamba` as break-glass clone tracked separately.