hermes 976b3f0005 docs: record the review follow-ups, with evidence for the one we declined
Second review round asked for three things. Two adopted, one measured and declined.

ADOPTED
  - Removing the Terminal plugin is recommended in writing as the right move (it is the
    largest attack surface, and macros already provide command execution). Left installed
    because it is the operator's plugin - removing a tool unilaterally is not the agent's
    call. Documented how: rename to Terminal.disabled (readDirectory() skips *.disabled).
  - Automatic password rotation and the deploy-key-read-only suggestion are recorded as
    operator decisions with their trade-offs.

DECLINED, WITH EVIDENCE
  - "php.ini should disable exec/shell_exec/passthru/system by default." Measured, this
    would break the editor's core function, so it cannot be a default:
        components/codegit/*   -> Common::safe_execute   31 call sites (every git op)
        components/macro/*     -> Common::raw_execute     1 call site
        common.php raw_execute -> function_exists("system") / function_exists("exec")
    Every commit, push and fetch from the editor runs through exec/system. It stays a
    deliberate exposure lever (S-7), not a default.

CORRECTED
  - Review claimed the redacted patch file had a syntax error. Verified on the guest with
    php83 -l: "No syntax errors detected". The placeholder is a plain string literal inside
    a double-quoted PHP string. That finding was wrong, and is recorded as such rather than
    "fixed" to satisfy a false positive.

Also fixed the section ordering in the doc.
2026-09-29 16:22:25 +10:00

atheos-blog-lxc

Provisioning for a browser-based code editor (Atheos) in an Alpine LXC, wired to Gitea, with the armistace/blog repository cloned and ready to edit.

Built with the AI-DLC workflow — the full process trail (requirements, design, units, decisions, audit log) lives in aidlc-docs/.


What this is

A small, single-purpose Proxmox container that puts an editor in your browser so you can write blog posts and commit them to Gitea — without VS Code, without a cloud IDE, and without a build toolchain.

Guest Proxmox LXC 136 on node scotty
OS Alpine 3.23.2 (unprivileged, OpenRC)
URL http://192.168.178.57/ — LAN only
Stack nginx → php-fpm 8.3 (unix socket) → Atheos IDE
Sizes 2 vCPU · 1 GB RAM · 20 GB rootfs · onboot=1
Editor Atheos — PHP, no database, real vim keybindings
Project armistace/blog cloned to /var/www/atheos/workspace/blog
Git auth per-repository deploy key (write-enabled)

What it deliberately is NOT

  • Not VS Code / code-server / Coder. Atheos is an independent, lightweight PHP editor.
  • Not a build environment. The blog is a Pelican site, but building/publishing happens in your existing pipeline. There is intentionally no Python, no pelican, no make here — the presence of Python would be a defect (verified by acceptance criterion AC-8).
  • Not internet-facing. No reverse proxy host, no DNS record, no port-forward is created.

Quick start

If you just want to use it:

  1. Open http://192.168.178.57/ and complete the Atheos first-run installer.
  2. ssh root@192.168.178.57, then set your git identity — see RUNBOOK.md STEP 1. Git will not let you commit until you do, and that is deliberate: the agent does not create your identity.
  3. Add the deploy key to armistace/blog and switch the remote to SSH — RUNBOOK.md STEP 2 & 3.

👉 The full operational guide is RUNBOOK.md. Start at STEP 1.


Repo layout

.
├── README.md                     this file
├── RUNBOOK.md                    ← operational guide; START AT STEP 1
├── docs/
│   ├── security-notes.md         credential model + hardening TODOs if ever exposed
│   ├── resiliency-notes.md       what a non-PoC deployment would need
│   └── writer-branch-workflow.md how writing/publishing works from the editor
├── files/
│   ├── atheos.conf               nginx vhost (install to /etc/nginx/http.d/atheos.conf)
│   ├── ssh-config                ~atheos/.ssh/config (the gitea-blog alias)
│   └── macros.db.php             installed copy of the Atheos writer macros
├── scripts/
│   ├── provision.sh              rebuild the whole guest from scratch
│   └── update-atheos.sh          update Atheos to latest upstream + re-pin
└── aidlc-docs/                   AI-DLC process trail (requirements → design → units → audit)

Rebuilding from scratch

The guest holds nothing unique — the blog's source of truth is Gitea — so a rebuild is cheap:

# on scotty (192.168.178.69), as root
pct destroy 136
sh scripts/provision.sh

scripts/provision.sh is written to be re-runnable and reproduces the documented build exactly, including the pinned Atheos commit and its verified tarball checksum.


Design decisions worth knowing

# Decision Why
D1 No git identity is configured by the agent. You set it (RUNBOOK STEP 1). You own the armistace identity; setting it programmatically would impersonate you and blur attribution (requirement FR-11).
D2 Atheos is pinned to a commit SHA, with update-atheos.sh to deliberately move it. Atheos has no releases; a moving branch is not reproducible.
D3 nginx :80, web root /var/www/atheos, php-fpm over a unix socket. Smallest network surface — nothing extra listens on the LAN.
D6 Per-repository deploy key, not a personal access token. A Gitea PAT's scopes are route groups matched against your whole account, so a stolen token reaches every repo you can write. A deploy key reaches exactly one.

Full rationale, including the alternatives that were rejected and the verification behind them, is in aidlc-docs/design-artifacts/application-design.md and docs/security-notes.md.


Security at a glance

  • Writing happens on a branch, never on master. The editor commits to a long-lived atheos-writer branch and you merge via PR in Gitea — see docs/writer-branch-workflow.md. ⚠️ This only holds if branch protection is enabled on armistace/blog's master — without it the deploy key could force-push master directly. Confirm with the branch_protections API call in that document.
  • Git auth: deploy key scoped to armistace/blog, private key mode 600, owned by the php-fpm user.
  • The SSH alias uses IdentitiesOnly yes, so no other key is ever offered.
  • The web app runs as a dedicated unprivileged user (atheos), which also owns the workspace.
  • ⚠️ Accepted risk: Atheos runs as a web app with shell-exec reach, so a compromise can use the deploy key to write blog. That is the intended floor (one repo, one branch) rather than the ceiling. Keep branch protection on blog's master.
  • If this is ever exposed to the wider web, work through docs/security-notes.md §2 first.

Provenance

Built 2026-09-29
AI-DLC stages executed Workspace Detection, Requirements, Workflow Planning, Application Design, Units Generation, Infrastructure Design, Code Generation, Build & Test
Stages skipped (with rationale) Reverse Engineering, User Stories, Functional Design, NFR Requirements, NFR Design — see aidlc-docs/plans/execution-plan.md
Atheos pin f90cd1806dbe0e25673a77e27390e8b1a240c3f6 (build 611), tarball sha256 03ebcb1479b59f1898b5fa50808b181750b42211698f7f7b4042cf2514d78b20
S
Description
Alpine LXC running Atheos (browser editor) wired to Gitea + armistace/blog. LAN-only. Built with AI-DLC.
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