---
model: gpt-5.6-sol
service: opencode
timestamp: 2026-08-28T17:29:43Z
git_ref: 2ca8c570
diff_cmd: git diff HEAD~1..HEAD
---

# Raw output - transport bindspace FD through Trio spawn

The human approved the next WireGuard Layer C increment after landing
pre-handshake child-death detection.

## Generated code

> `git diff HEAD~1..HEAD -- tractor/_child.py tractor/runtime/_supervise.py tractor/spawn/_spawn.py tractor/spawn/_trio.py tractor/spawn/_mp.py tractor/to_actor/_api.py tests/test_netns_spawn.py`

Thread an optional live `Bindspace` through actor spawn APIs. For the
Trio backend, duplicate its namespace FD, append that temporary
descriptor to existing `pass_fds`, and send the atomic descriptor/inode
pair through the child CLI. Close the parent temporary duplicate as
soon as `open_process()` returns, raises, or is cancelled, while the
child consumes its inherited descriptor before runtime startup.

Reject bindspace transport explicitly in multiprocessing backends until
their descriptor-reduction slice is implemented. Add privilege-free
tests for CLI forwarding, merged pass-FD state, caller immutability,
source/duplicate ownership, exec failure, cancellation, absent live
authority, death-before-handshake cleanup, and MP rejection.

## Scope boundary

Multiprocessing FD reduction and root-process namespace entry remain
follow-up work.