Commit graph

11 commits

Author SHA1 Message Date
Gergo Magyar
abbcacebca refactor(devcontainer): hybrid AI CLI config — read-only host share + per-container credentials
Restructure the Claude Code / Codex / Cursor mount topology to fix the
silent first-run-UI bug surfaced in PR testing, and to harden against
the host-write-through escape class the previous bind-mount design
exposed.

The actual root cause of the first-run wizard firing on the user's
screenshot — confirmed via three parallel research agents (best
practices, framework docs deep dive of the OpenAI Codex Rust source,
adversarial design review) — was NOT a credential permission check.
Claude Code splits state across `~/.claude/.credentials.json` AND
`~/.claude.json` (a FILE at $HOME, sibling of the `.claude/` dir).
The latter holds `hasCompletedOnboarding`, `userID`, `oauthAccount`
metadata, MCP user-scope config, and per-project trust state — and
Claude Code reads it at literal `$HOME/.claude.json`, not via
`CLAUDE_CONFIG_DIR`. The previous design mounted `~/.claude/` but
left `~/.claude.json` outside the topology entirely, so every container
started with a missing onboarding-state file and re-ran the wizard.

Confirmed by tfvchow/field-notes-public#10:
"Persisting .credentials.json alone is NOT sufficient. Without
.claude.json, Claude Code treats the session as a fresh install and
prompts for login regardless of valid credentials being present."

The new topology:

**Mounts**
- `${localEnv:HOME}/.claude` → `/host/.claude` (read-only bind)
- `${localEnv:HOME}/.codex` → `/host/.codex` (read-only bind)
- `${localEnv:HOME}/.cursor` → `/host/.cursor` (read-only bind)
- `${localEnv:HOME}/.claude.json` → `/host/.claude.json` (read-only bind)
- `claude-config-${devcontainerId}` → `/home/node/.claude` (named volume)
- `codex-config-${devcontainerId}` → `/home/node/.codex` (named volume)
- `cursor-config-${devcontainerId}` → `/home/node/.cursor` (named volume)

**containerEnv** gains `CODEX_HOME=/home/node/.codex` (Codex's own env
override, per its public Rust source). `CLAUDE_CONFIG_DIR=/home/node/
.claude` was already set.

**`post-create.sh`** stages the named volumes on first run:

- Symlinks shareable subdirs from `/host/.claude` into the named volume:
  `plugins/`, `skills/`, `agents/`, `memory/`, `commands/`. Codex gets
  `config.toml` symlinked. Cursor has no shareable subdirs (cli-config
  .json conflates auth and settings).
- Copies `.credentials.json`, `auth.json`, `cli-config.json` on first
  run with `chmod 600`. After first run, container manages its own
  refresh; host's credentials untouched.
- Copies `~/.claude.json` on first run (with stub
  `{"hasCompletedOnboarding":true,"installMethod":"global"}` fallback
  for hosts that haven't run Claude Code). This is the fix for the
  observed onboarding-wizard loop.

`ensure-host-config-dirs.cjs` now also touches `~/.claude.json` on the
host if missing, so the bind mount has a valid source on hosts that
have never run Claude Code.

**Why read-only + named volume vs. the previous full bidirectional
bind mount:**

1. **Host filesystem write-through escape, eliminated.** Previous
   design symlinked `plugins/`, `agents/`, `skills/` write-through
   into the host's `~/.claude/` — a malicious npm package in the
   workspace dep tree could drop `agents/evil.md` into the host's
   config, which the next host Claude session would auto-load. The
   read-only `/host` mount blocks this; container compromise no
   longer persists across teardown via host-side autoload.
2. **Windows bind-mount perm-flattening, sidestepped.** Files
   surfaced through a Docker Desktop Windows bind mount appear as
   `root:root` mode `777`. Credentials in the named volume come with
   proper Linux ownership and `chmod 600` — what each CLI expects on
   write (none enforces on read, but write-side hygiene matters for
   the host's understanding of "where credentials live").
3. **No `ide/` lock-file collisions.** Previous design symlinked
   `~/.claude/ide/` write-through, including per-PID lock files. Host
   PID and container PID namespaces are unrelated → lock-file PIDs
   misclassify dead processes as alive. Skipping `ide/` keeps lock
   files container-local.
4. **No `projects/` ghost dirs.** Host encodes the workspace path as
   `D--development-coding-GitNexus`, container as `-workspace`.
   Bidirectional `projects/` symlinks would split memory and session
   state across two ghost project dirs for what is conceptually the
   same project. Skipping `projects/` keeps per-project state
   container-local; host's projects/ stays untouched.
5. **No `settings.json` version drift.** Container is pinned to a
   specific Claude Code version (`CLAUDE_CODE_VERSION` build arg);
   host floats with auto-update. Bidirectional `settings.json` writes
   produced silent schema rollback. Skipping settings.json keeps each
   side authoritative for its own version.

**README** rewritten in the same section to describe the new topology
honestly: what's shared, what isn't, the OAuth refresh-token
divergence between host and container, per-CLI quirks (macOS Keychain
storage, Cursor's known upstream in-container auth bug, Codex
keyring storage). Trust-boundary section updated to name the threat
model accurately — same read surface as before (malicious dep can
still READ all credentials), but write-through into host plugin/agent
dirs is now blocked.

Verified locally: `@devcontainers/cli read-configuration` resolves all
19 mounts correctly on Windows, `post-create.sh` parses, and
`ensure-host-config-dirs.cjs` idempotently touches `~/.claude.json`.

Research backing this design:

- Anthropic Claude Code devcontainer docs (named-volume pattern):
  https://code.claude.com/docs/en/devcontainer
- tfvchow/field-notes-public#10 (both files required):
  https://github.com/tfvchow/field-notes-public/issues/10
- anthropics/claude-code#29029 (VS Code extension strips
  hasCompletedOnboarding):
  https://github.com/anthropics/claude-code/issues/29029
- OpenAI Codex Rust source (no read-side perm check):
  https://github.com/openai/codex/blob/main/codex-rs/login/src/auth/storage.rs
- Cursor CLI in-Docker auth issue:
  https://forum.cursor.com/t/cursor-agent-authentication-issue-inside-docker/143995
2026-05-28 15:31:02 +01:00
Gergo Magyar
6a569e401e feat(devcontainer): bind-mount ~/.docker, ~/.aws, ~/.azure for agent workflows
Extend the host bind-mount surface so coding agents inside the container
inherit cloud + container-registry auth from the host without any
per-container setup:

- ~/.docker (read-write) — Docker registry auth (config.json) + buildx
  config. Container-registry pushes (ghcr.io, docker.io) from inside the
  container pick up host `docker login` state. Read-write because the
  Docker CLI refreshes credential-helper tokens.
- ~/.aws (read-only) — AWS CLI / SDK credentials. Read-only because
  rotating creds typically happens via the host. Empty on this dev box,
  so forward-compatible: the moment you `aws configure` on the host the
  container picks it up on the next rebuild.
- ~/.azure (read-only) — Azure CLI credentials. Same pattern as ~/.aws.

`ensure-host-config-dirs.cjs` extends to mkdir these three on init so
the bind mounts always have a valid source even if a CLI has never been
used on this host.

The Docker CLI itself isn't installed in the container by default — the
~/.docker/ mount is inert until you add `docker-outside-of-docker:1` or
similar Feature. README now calls this out under "What you still don't
have inside the container" so it's obvious which CLIs are agent-ready
and which need a feature add to become useful.

README updates:

- Bind-mount table gains a "Why" column and rows for the three new
  mounts, making it clear at a glance what each one enables.
- Trust-boundary section lists Docker registry tokens, AWS, and Azure
  creds in the read-side exfil path so the threat model stays honest as
  the credential surface grows.
- New subsection lists not-included CLIs (Docker, AWS, Azure, gcloud,
  kubectl, private-npm) with the exact Feature ID or mount snippet
  needed to enable each — turns "I want my agent to do X" into a
  one-line config change.

Verified locally: `npx @devcontainers/cli read-configuration` resolves
all 9 host bind mounts to valid C:\Users\<name>/* paths on Windows.
2026-05-28 14:23:30 +01:00
Gergo Magyar
213390a4b5 fix(devcontainer): drop ~/.gitconfig bind mount; defer to VS Code auto-copy
VS Code's Dev Containers extension auto-copies the host's gitconfig into
the container at attach time using `(dd ...) >> /home/node/.gitconfig`.
A read-only bind mount of ~/.gitconfig blocks that write, so attach
failed with `cannot create /home/node/.gitconfig: Read-only file system`.
Making it read-write would let the append succeed, but the bind mount
means the host file and the container file are the same file — VS Code's
append would double the host gitconfig contents on every container
start.

Drop the ~/.gitconfig bind mount entirely. VS Code's auto-copy is the
purpose-built mechanism for this, gives the container the host's
user.name / user.email transparently, and avoids both the read-only
write failure and the append-duplication trap. The container ends up
with a writable /home/node/.gitconfig that's a copy of the host's, not
a mount.

The remaining six bind mounts (.claude, .codex, .cursor, .ssh, .config/git,
.config/gh) keep their existing modes — XDG-style git config under
~/.config/git is unaffected by VS Code's auto-copy (which only targets
~/.gitconfig), so its read-only bind mount stays.

Also remove the `.gitconfig` touch from ensure-host-config-dirs.cjs
(now unnecessary) and update the README CLI-state table, sharing
explanation, and troubleshooting row to reflect that gitconfig flows
in via VS Code auto-copy rather than the bind mount.
2026-05-28 14:14:36 +01:00
Gergo Magyar
f592c804ed fix(devcontainer): Node-based initializeCommand; bind-mount .ssh + .config/git
Two fixes bundled:

1. The previous commit's OS-keyed `initializeCommand` object was based
   on a misread of the Dev Containers spec. The object form on command
   properties is **named parallel tasks**, not OS dispatch — VS Code ran
   all three keys in parallel via cmd.exe on Windows, the POSIX branches
   failed, and container creation aborted before Docker was invoked.

   Restore the single-string Node-based form:
   `node .devcontainer/ensure-host-config-dirs.cjs`. Node works
   identically in cmd.exe on Windows and bash/zsh on Linux/macOS/WSL,
   and `os.homedir()` respects $HOME on POSIX and %USERPROFILE% on
   Windows. The script is idempotent (mkdirSync recursive is a no-op
   for existing dirs; touch is gated on .gitconfig existence).

   Document Node ≥18 on the host as the only host-side prerequisite
   beyond Docker Desktop and the VS Code Dev Containers extension.
   Anyone running Claude Code on the host already has it.

2. Extend the host-bind mount surface with `~/.ssh` and `~/.config/git`,
   both read-only:

   - `~/.ssh` lets commit signing + push over SSH remotes work inside
     the container without copying private keys. Read-only mount means
     container code can read keys but can't modify or delete them.
     (Threat: a malicious dep can still read private keys from inside
     the container; the read-only mount narrows write-side blast
     radius, not read-side. Documented in the trust-boundary section.)
   - `~/.config/git` covers XDG-style git config (`~/.config/git/config`,
     `~/.config/git/ignore`, `~/.config/git/attributes`) for users who
     keep settings there instead of `~/.gitconfig`. Read-only, same as
     `~/.gitconfig`.

   Update the CLI-state-sharing table and trust-boundary paragraph to
   reflect the expanded surface.

Re-adds .devcontainer/ensure-host-config-dirs.cjs (deleted before the
OS-keyed attempt).
2026-05-28 13:52:38 +01:00
Gergo Magyar
32cb7dc28a fix(devcontainer): cross-platform initializeCommand + soften Windows-native posture
The previous commit's `initializeCommand` was POSIX-only (`mkdir -p $HOME/...`).
VS Code on Windows runs the host shell as `cmd.exe /c ...`, which can't
parse POSIX syntax — `$HOME` doesn't expand, `mkdir -p` errors, the init
fails with `The syntax of the command is incorrect`, and container
creation aborts before Docker is invoked.

Switch `initializeCommand` to the spec's OS-keyed object form:
- linux/darwin (covers WSL2 because VS Code runs initializeCommand in
  the WSL shell when attached via the WSL extension): POSIX mkdir+touch,
  as before
- win32: PowerShell snippet that creates the same directories under
  $USERPROFILE and touches the gitconfig if missing

Soften the README's hard "WSL2 required" framing from the previous
commit. Reality per `@devcontainers/cli read-configuration` output:
`${localEnv:HOME}` on Windows-native resolves to `C:\Users\<name>`
(VS Code falls back to USERPROFILE), so the bind mount sources are
valid Windows paths and Docker Desktop handles the translation. The
earlier `accessing specified distro mount service` failure was a
separate Docker Desktop WSL-integration issue, not a HOME-resolution
issue. Windows-native works; it's just slower with more bind-mount
permission edge cases (the husky/_/h EPERM class). The README now
explains the tradeoff and steers toward WSL2 for performance + file
watchers + permission reliability, rather than blocking Windows-native
checkouts outright.

Update the troubleshooting row to reflect the new posture.
2026-05-28 13:46:13 +01:00
Gergo Magyar
cd8ac5f6d1 refactor(devcontainer): address ce-code-review findings (P0 + 4 × P1 + 8 × P2 + 2 × P3)
Walkthrough resolution of the 16-finding ce-code-review on PR #1875. 15 of
16 findings applied; one (F12, Anthropic Feature floating tag) was
superseded by F6's Feature removal.

P0
- F1: WSL2 is now REQUIRED for Windows hosts, not just recommended.
  ${localEnv:HOME} resolves to empty string on Windows-native (no HOME env
  var) — bind mounts then point at /.claude, /.codex etc. and silently
  break. ensure-host-config-dirs.cjs wrote to USERPROFILE-derived paths
  via os.homedir(), so the two surfaces disagreed about which env var was
  "home" on Windows. README header reframed; "Windows 11 — WSL2 is required"
  section explains the mismatch concretely.

P1
- F2: Workspace `node_modules` volume names now include `-${devcontainerId}`
  so two GitNexus checkouts on the same host (~/work/GitNexus and
  ~/projects/GitNexus) don't share volumes and corrupt each other's
  installs.
- F3 + F5: `postCreateCommand` extracted to `.devcontainer/post-create.sh`
  with `set -euo pipefail` and six labeled echo steps so failure logs
  name the step instead of an opaque &&-chain index. Chown step extended
  to cover /home/node/.npm, /commandhistory, and /home/node/.local — these
  named-volume mount points were owned by build-time UID 1000 but the
  container's `node` is re-IDed at runtime by updateRemoteUserUID on
  non-1000 Linux hosts, leaving them unwritable until now.
- F4: Cursor installer downloaded to a temp file with curl --retry +
  --max-time; sha256 logged to build output before execution so drift
  across rebuilds is visible in CI logs. Full hard-pin (to a versioned
  downloads.cursor.com tarball with verified sha256) tracked as a
  follow-up in README "What's not included".

P2
- F6: Anthropic Feature replaced with a direct
  `npm install -g @anthropic-ai/claude-code@${CLAUDE_CODE_VERSION}` so
  CLAUDE_CODE_VERSION actually pins the installed binary (the Feature
  ignored the ARG and pulled latest at install time). Honors the
  earlier "pin known-good versions" decision and resolves F12's
  floating-tag concern for this Feature.
- F7: Dockerfile ARG defaults dropped for the three version vars;
  `devcontainer.json` `build.args` is now the single source of truth.
  Standalone `docker build .devcontainer/` must pass --build-arg.
- F8: ensure-host-config-dirs.cjs deleted; `initializeCommand` now uses
  POSIX `mkdir -p` + `touch ~/.gitconfig` directly, dropping the
  host-Node-on-PATH prerequisite that broke on fresh Windows+Docker
  Desktop installs without Node.
- F9: ~/.gitconfig bind-mounted read-only so `git commit` inside the
  container uses the host's user.name / user.email. Read-only so
  container-side `git config --global` doesn't leak to host.
- F10: ~/.config/gh bind-mounted (read-write) so `gh pr create` /
  `gh pr checks` / `gh issue create` work inside the container without
  re-auth. AGENTS.md's commit + PR workflow now fully functional for
  agents inside the container.
- F11: CLAUDE_CONFIG_DIR removed from Dockerfile ENV; canonical value
  lives only in devcontainer.json containerEnv. Eliminates the two-file
  edit risk.
- F13: Mounts comment now documents per-instance vs per-workspace-name
  scoping rationale so future contributors don't guess.
- F14: README "Trust boundary, concretely" paragraph names the exfil
  path explicitly (malicious npm postinstall → OAuth tokens →
  ~/.claude/projects/<workspace>/memory/MEMORY.md secrets) and lists
  vendor-side rotation runbook entries.

P3
- F15: Dockerfile pre-create + chown of /home/node/.claude, .codex,
  .cursor dropped — those paths are bind-mounted, which fully shadows
  any image-side ownership. Only .npm, .local, /commandhistory still
  benefit from the pre-create.
- F16: README "Bumping CLI versions" section rewritten against the
  post-F6 reality: CLAUDE_CODE_VERSION and CODEX_VERSION are real
  pins; CURSOR_VERSION is informational only.

Verified locally: `docker build .devcontainer/ --build-arg ...` succeeds.
Smoke-tested image: `claude --version` (2.1.153), `codex --version`
(0.134.0), `cursor-agent --version` all resolve as the non-root `node`
user; named-volume mount points (/home/node/.npm, /commandhistory) are
node-owned at build time so non-1000 host UIDs get the post-create.sh
chown fix instead of EACCES.
2026-05-28 13:38:50 +01:00
Gergo Magyar
35e61a9e66 feat(devcontainer): bind-mount host CLI config dirs for plugin/skill/memory sync
Switch the credential/config mounts from per-devcontainer named volumes
to bind mounts of `${localEnv:HOME}/.claude`, `~/.codex`, and
`~/.cursor`. Effect inside the container:

- Authentication is shared with the host. If you've already run
  `claude login` / `codex login --device-auth` / `cursor-agent login`
  on the host, you're already authenticated in the container.
- Plugins, skills, agents, memory, and settings sync both ways. Install
  a plugin in the container, it shows up on the host; add a custom
  agent on the host, the container sees it immediately.
- All devcontainers on the host share the same CLI state, mirroring
  how host shells already share it. (Per-workspace isolation of plugins
  was never a stated requirement; the previous per-devcontainer named
  volumes leaked nothing useful.)

Add `.devcontainer/ensure-host-config-dirs.cjs` and wire it as
`initializeCommand`. It runs on the host before container create and
guarantees `~/.claude`, `~/.codex`, `~/.cursor` exist, so Docker doesn't
reject the bind mount when a CLI has never been used on this host.
Cross-platform via Node `os.homedir()` + `fs.mkdirSync({recursive: true})`;
idempotent; no third-party deps.

Update `.devcontainer/README.md`:
- New "How CLI state is shared with your host" section explaining the
  bind-mount model up front so users know their host plugins/skills/
  memory carry into the container.
- Mark first-time-login section as skippable when the user is already
  authenticated on the host.
- Note the high-trust escape hatch: replace the three bind mounts with
  `type=volume` named volumes if the host/container trust boundary
  needs to be separated (Anthropic's reference pattern for enterprise).
- Replace the obsolete "rm named volume" troubleshooting row with one
  that covers EACCES/EPERM on the host-bind-mount path.
2026-05-28 12:27:40 +01:00
Gergo Magyar
a75fc2e060 fix(devcontainer): clear stale .husky/_ before npm install
When `npm install` runs the root `prepare` script (husky), husky tries
to copyfile `node_modules/husky/husky` → `.husky/_/h`. On Docker Desktop
Windows bind mounts, if `.husky/_/` already exists from a prior
container run, the new container's `node` user can't overwrite it via
the bind mount's permission translation and the install fails with:

  Error: EPERM: operation not permitted, copyfile
    '/workspace/node_modules/husky/husky' -> '.husky/_/h'

Drop `.husky/_` defensively in `postCreateCommand` before `npm install`
so husky always starts from a clean slate. `.husky/_` is a husky
runtime cache (gitignored), so removing it has no effect on the repo —
husky regenerates it. No-op for WSL2-side checkouts (where this class
of bind-mount permission collision doesn't occur).

Add a troubleshooting row to `.devcontainer/README.md` covering the
manual recovery (`rm -rf .husky/_` on the host) and the long-term fix
(clone in WSL2 — Windows-side bind mounts will keep biting on this
kind of issue across rebuilds with different UID alignment).
2026-05-28 12:19:37 +01:00
Gergo Magyar
326cb06fe7 fix(devcontainer): install gitnexus-web before gitnexus in postCreateCommand
The previous order (root → gitnexus-shared → gitnexus → gitnexus-web)
broke at the `gitnexus` install step because `gitnexus`'s `prepare`
script runs `scripts/build.js`, which compiles `gitnexus-web` whenever
its source tree exists. In the devcontainer the entire workspace is
bind-mounted, so `gitnexus-web/` is present from the start — but its
`node_modules/` wasn't yet, so `tsc -b` failed with:

  error TS2688: Cannot find type definition file for 'vite/client'
  error TS2688: Cannot find type definition file for 'node'

Reorder so `gitnexus-web` installs before `gitnexus`. Verified
end-to-end via `npx @devcontainers/cli up`: container builds clean,
all three CLIs (Claude 2.1.153, Codex 0.134.0, Cursor) respond, and
`npx tsc --noEmit` inside `/workspace/gitnexus` passes.

Production Dockerfiles (`Dockerfile.cli` etc.) don't hit this because
they only COPY `gitnexus/` + `gitnexus-shared/`, so `gitnexus-web/`
doesn't exist at install time and `scripts/build.js` skips the web
step. The devcontainer's full-tree bind mount changes that calculus.
2026-05-28 11:58:12 +01:00
Gergo Magyar
05e9c58fb1 fix(devcontainer): make interactive login the default auth path for all CLIs
The previous `containerEnv` injected `CURSOR_API_KEY: "${localEnv:CURSOR_API_KEY}"`.
When the host had no `CURSOR_API_KEY` set, this resolved to an empty
string and Docker injected `CURSOR_API_KEY=""` into the container.
Cursor CLI treats a set-but-empty `CURSOR_API_KEY` as "use this key"
rather than "fall back to stored login", which silently broke
`cursor-agent login` on the most common path — users who hadn't
explicitly opted into API key auth.

Drop `CURSOR_API_KEY` from `containerEnv`. Login is now the
unconditional default for all three CLIs (Claude Code, Codex CLI,
Cursor CLI); the named-volume + Dockerfile-chown pattern keeps
credentials persistent across container rebuilds for every login path.

Reorganize the README's auth section to put login first for all three
CLIs uniformly (matching the new behavior) and move API key
authentication into a separate "Alternative" section for CI/headless
use. Document that API keys are intentionally not auto-propagated from
the host and explain the export-in-shell or VS Code dotfiles-repo paths
for users who want them. Update the troubleshooting row to reflect the
new design.
2026-05-28 11:14:02 +01:00
Gergo Magyar
9c07ef9cf9 feat(devcontainer): add cross-platform devcontainer for Claude Code, Codex, and Cursor CLIs
Add a Dev Container that pre-installs Claude Code (2.1.153, via Anthropic's
official Feature), OpenAI Codex CLI (pinned 0.134.0), and Cursor CLI alongside
the GitNexus native build chain. Opens via VS Code's Dev Containers extension
on Windows 11 (Docker Desktop + WSL2), macOS, or Linux without OS-specific
branches in devcontainer.json.

Topology and base
- Base image `mcr.microsoft.com/devcontainers/typescript-node:1-22-bookworm`
  (multi-arch, monthly patched, ships the `node` non-root user, zsh, `gh`).
- Node 22 LTS satisfies `gitnexus/`'s engines `>=22.0.0` and matches the
  `node:22-bookworm-slim` SHA-pinned base used by `Dockerfile.cli`.
- Single container with all three CLIs co-installed (vs. docker-compose
  per-tool) — prevailing 2026 community pattern, lowest daily-driver friction.

Persistence and auth
- Per-devcontainer named volumes scoped by `${devcontainerId}` for
  `/home/node/.claude`, `/home/node/.codex`, `/home/node/.cursor`,
  `/commandhistory`, and `/home/node/.npm`. Authentication survives rebuilds
  without leaking between workspaces.
- Four sub-workspace `node_modules` volumes (root, gitnexus, gitnexus-web,
  gitnexus-shared) keep tree-sitter native bindings and onnxruntime off the
  bind mount — the actual Win/Mac perf win.
- Credential mount paths are pre-created in the Dockerfile with
  `chown node:node` BEFORE `USER node`, so empty named volumes inherit
  correct ownership on first mount and first-run logins don't EACCES.
- `CURSOR_API_KEY` is injected via `containerEnv: ${localEnv:CURSOR_API_KEY}`
  (Cursor's documented headless path); falls back to interactive
  `cursor-agent login` when the host env var is unset.

Build-arg promotion
- Build args (`CLAUDE_CODE_VERSION`, `CODEX_VERSION`, `CURSOR_VERSION`, `TZ`)
  are promoted to ENV in the Dockerfile so lifecycle commands and shells can
  resolve them. Without this promotion, Docker ARG values are build-only and
  silently no-op at lifecycle time.

Workspace setup
- `postCreateCommand` chowns the four workspace `node_modules` volumes
  (Docker creates them root-owned), then installs in dependency order:
  root → gitnexus-shared (install + build) → gitnexus → gitnexus-web. The
  shared package must build before its consumers (`file:../gitnexus-shared`).

Ports
- 5173 (Vite dev) and 4173 (Vite preview) auto-forwarded.
- 4747 (`gitnexus serve`) marked `requireLocalPort: true` because
  `gitnexus-web/src/services/backend-client.ts` hardcodes
  `http://localhost:4747` as the default backend URL; a remapped port would
  silently break the web UI.

VS Code integration
- Recommended extensions: `anthropic.claude-code`,
  `dbaeumer.vscode-eslint`, `esbenp.prettier-vscode`, `eamodio.gitlens`.
- Settings: format-on-save with Prettier, ESLint auto-fix on save, zsh as
  default terminal profile, persistent zsh history via `HISTFILE` →
  `/commandhistory`.

Documentation
- `.devcontainer/README.md` covers WSL2 setup (clone inside WSL2 for IO and
  file-watcher reliability), first-time auth flows for each CLI, port-
  forwarding notes, LadybugDB container limitations, and the bumping
  procedure for each CLI version.
- `CONTRIBUTING.md` gets a "Containerized development (optional)"
  subsection pointing at the devcontainer README.

Deferred to a follow-up PR
- Opt-in egress firewall (originally planned as a fourth implementation
  unit). The Dev Containers spec makes `runArgs` static — toggling
  `NET_ADMIN`/`NET_RAW` capabilities cleanly requires either a separate
  `devcontainer-firewall.json` profile or an `initializeCommand`-generated
  overlay. Keeping this PR focused on the working baseline.
- Codespaces-specific tuning (works incidentally when the firewall is off,
  not actively tested).
- Inside-container Playwright e2e (needs Chromium libs not in the base
  image).

Verification deferred to user
- This change introduces a new dev tooling artifact. Validate by running
  `docker build .devcontainer/`, opening the repo in VS Code via
  "Dev Containers: Reopen in Container", confirming `claude --version`,
  `codex --version`, `cursor-agent --version` resolve inside the container,
  and `cd gitnexus && npm run test:unit` runs clean against the
  named-volume `node_modules`.
2026-05-28 09:13:56 +01:00