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+# DevGuard upstream-adapter packet (2026-09-28)
+
+This note points CodeSpace agents and reviewers to DevGuard's W0–W2 packet for CS-DG-UPSTREAM-ADAPTER-WORK-SPEC-1 v1.0. It is a dated, non-normative record, not part of the documentation site. It approves no architecture, dependency, pin, experiment or merge, and it changes no CodeSpace behaviour. Re-query GitHub and git before acting.
+
+- Living trackers: [#76](https://github.com/novelKR/CodeSpace/issues/76) (CodeSpace) and [novelKR/DevGuard#14](https://github.com/novelKR/DevGuard/issues/14) (primary, cross-repository).
+- The packet: [novelKR/DevGuard#16](https://github.com/novelKR/DevGuard/pull/16), file [`docs/handoff/2026-09-28-upstream-adapter-packet.md`](https://github.com/novelKR/DevGuard/blob/a67facbbebb192d83126c5afa1a9ef2d713c2e2e/docs/handoff/2026-09-28-upstream-adapter-packet.md) at head `a67facbbebb192d83126c5afa1a9ef2d713c2e2e`. The same PR carries the specification and its start instruction.
+- The owner's policy direction, recorded on both trackers: DevGuard may use Codex and other external dependencies behind adapters, with reviewed, explicit upstream pins. CodeSpace's own pin and review process is unchanged.
+
+## Unchanged in CodeSpace
+
+- The Codex pin: `6b9826e3aa83b1a5947db50f4332cb9c65f1b340` (rust-v0.154.0), `docs/upstream-lock.md` and the gitlink.
+- Every documentation page, including the CS-RG hold notices from #75. The CS-RG suspension stays in force.
+- Manifests, locks, scripts, CI policy and the Codex adapters.
+- The governance-free `off` path: it needs no DevGuard dependency, service or credential.
+
+## Findings that concern CodeSpace
+
+These are summaries; the packet has the citations and evidence levels.
+
+- **Upstream PTY API (packet section 7).** `ChildFds::Attached` exists at rust-v0.159.0-alpha.11 (`72b8d8b`) and Codex `main`, not in stable rust-v0.157.1. From that revision on, the last parameter of `spawn_pty_process` is `ChildFds<'_>`. A pin move past stable would therefore need a coordinated edit of `crates/pty/src/lib.rs:66-77` in the reviewed pin PR, for example `ChildFds::Inherited(&[])`, which keeps today's behaviour. No pin change is proposed.
+- **Descriptor inheritance on macOS (sections 8 and 11).**
+  - Rust std and tokio do not create pipes and sockets close-on-exec atomically on macOS, and std `Command` does not use `POSIX_SPAWN_CLOEXEC_DEFAULT`.
+  - The BD-1 diagnostic exercised `codex-utils-pty` at `72b8d8b` in a scratch crate outside both repositories. In it, unrelated std and tokio children received a transient PTY master in 104 of 2000 cases and pipe ends in 39 of 2000, from other threads' creation windows.
+  - By inference, the same applies to CodeSpace's Tokio pipe path, patch helper and sandbox probe, which spawn without child-side exclusion. The effect on CodeSpace, such as a delayed EOF, was not measured.
+  - An independent CodeSpace descriptor-hygiene proposal is an optional owner decision (packet section 14, decision 9). CS-RG does not justify it.
+- **Dependency gates (section 6).**
+  - `scripts/check-no-model-deps.sh` checks only direct `codex-*` keys in core manifests.
+  - `scripts/upstream_dependencies.py` rejects named crates only: the four `FORBIDDEN` names at any depth from every product root, plus `RUNNER_FORBIDDEN` from the Runner.
+  - So a transitive `codex-utils-pty` arriving through a DevGuard client would not be flagged today.
+  - The packet drafts an executable single-identity and transitive check for the PR in which a DevGuard crate first enters a CodeSpace graph. Nothing is applied.
+- **Pipe observation (section 9.2).** Tokio 1.53.1 offers no non-reaping exit observation. The packet identifies no thin, backend-owned pipe facility. A peek added to CodeSpace's own wait loop would conflict with the specification (its section 8.1) unless the owner rules it a generic capability of the existing backend; the packet does not recommend it.
+
+## Wording the packet drafts (not applied)
+
+| Page, lines at `326bdcb` | Current point | Draft direction |
+| --- | --- | --- |
+| `docs/codex-reuse.md:78` (ko `:96`) | "D3, DevGuard. No Codex dependency is added to DevGuard now…" | D3 superseded: DevGuard may consume Codex behind declared adapters with reviewed pins; CodeSpace's generic resource client imports no Codex types; CodeSpace's pin process unchanged |
+| `docs/upstream-update.md:90-131` (ko `:91-129`), under the hold notice | "The planned resource client must bring no transitive Codex dependency…", documentation only (`:94`) | kept, plus: a DevGuard binding linked into a CodeSpace executable consumes Codex through this repository's gitlink, with an executable single-identity check |
+
+Any change to these pages is a separate, reviewed CodeSpace PR with its Korean pages and registry hashes (packet decision 7).
+
+## Status at writing (2026-09-28, about 04:20 UTC)
+
+| Item | State |
+| --- | --- |
+| `main` | `326bdcb181f62f61bcb3c4e9c3de7535d50b0232`, the merge of #77. CI 36336337315 and documentation 36336337674 passed. Scheduled run 36355653598 on the same commit passed, with no ETXTBSY recurrence in that run |
+| novelKR/DevGuard#16 | Open at head `a67facbbebb192d83126c5afa1a9ef2d713c2e2e`; waits for the owner's exact-head decision |
+| This note's PR | Open; see #76 for its number and head |
+| novelKR/DevGuard#13 | Open at `edf5e2f20f88feed55822a078abffc18af5f9a4e`; a separate decision |
+
+## Next step and stop boundary
+
+The next step is the owner's decisions in packet section 14: merges at exact heads, the bounded experiments A, B and C, and normative reconciliation. Until then there is no merge, no experiment, no normative PR, no pin, dependency, service or credential change, and no upstream submission.
+
+If the packet changes before this note merges, this note is updated to the new head first.