---
model: claude-opus-4-7[1m]
service: claude
session: subints-spawner-phase-a-impl
timestamp: 2026-04-17T03:58:05Z
git_ref: 61a73ba
scope: code
substantive: true
raw_file: 20260417T035800Z_61a73ba_prompt_io.raw.md
---

## Prompt

Follow-up from the design session logged in
`20260417T034918Z_9703210_prompt_io.md`: the user
greenlit Phase A after `/prompt-io` tracking, so
execute the Phase A "modularize `spawn._spawn`" plan
end-to-end in a new worktree — four logical steps
(pytest harness prep, `trio_proc` extraction,
`mp_proc` extraction, docstring refresh), each green
via `/run-tests`.

User directives during execution:
- **Option 3** for the test cadence ("continue A.2–A.4
  first, then run the full suite once at the end of
  Phase A").
- **One commit** for the whole phase ("can't we just
  commit the whole patch in one commit?") instead of
  the 3/4-commit split I initially proposed.
- **Don't pre-draft** commit messages — wait for the
  user to invoke `/commit-msg` (captured as feedback
  memory `feedback_no_auto_draft_commit_msgs.md`).

## Response summary

Produced the cohesive Phase A modularization patch,
landed as commit `61a73bae` (subject: `Mv
trio_proc`/`mp_proc` to per-backend submods`). Five
files changed, +565 / -418 lines.

Key pieces of the patch (generated by claude,
reviewed by the human before commit):
- `tractor/spawn/_trio.py` — **new**; receives
  `trio_proc()` verbatim from `_spawn.py`; imports
  cross-backend helpers back from `._spawn`.
- `tractor/spawn/_mp.py` — **new**; receives
  `mp_proc()` verbatim; uses `from . import _spawn`
  for late-binding access to the mutable `_ctx` /
  `_spawn_method` globals (design decision made
  during impl, not the original plan).
- `tractor/spawn/_spawn.py` — shrunk 847 → 448 LOC;
  import pruning; bottom-of-module late imports for
  `trio_proc` / `mp_proc` with a one-line comment
  explaining the circular-dep reason.
- `tractor/spawn/__init__.py` — docstring refresh
  describing the new layout.
- `tractor/_testing/pytest.py` — the valid-backend
  set now comes from `typing.get_args(SpawnMethodKey)`
  so future additions (`'subint'`) don't need harness
  edits.

## Files changed

See `git diff 61a73ba~1..61a73ba --stat`:

```
 tractor/_testing/pytest.py |  12 +-
 tractor/spawn/__init__.py  |  31 +++-
 tractor/spawn/_mp.py       | 235 ++++++++++++++++++++++++
 tractor/spawn/_spawn.py    | 413 +-------------------------------
 tractor/spawn/_trio.py     | 292 ++++++++++++++++++++++++++++
 5 files changed, 565 insertions(+), 418 deletions(-)
```

Validation:
- import probe + `_methods` wiring check — OK
- spawn-relevant test subset — 37 passed, 1 skipped
- full suite — 350 passed, 14 skipped, 7 xfailed, 1
  xpassed

## Human edits

None — committed as generated by claude (no diff
between `.claude/git_commit_msg_LATEST.md` and the
committed body, as far as the assistant could
observe).
