---
name: unit-lane-inprocess-isolation
description: "releases#47 closed — threaded cargo test shares env block + inheritable-handle table; ambient prod writes (FF loudness path) cross-mint into with_home windows or the REAL live home; unit lane converted to nextest"
metadata: 
  node_type: memory
  type: project
  originSessionId: 6c0a72dc-b7e0-4516-9fc1-23f61e6c2c50
  modified: 2026-07-31T05:06:42.426Z
---

releases#47 (thin unit(Windows) reds at golden-green shas) closed 2026-07-30: lane fix/unit-lane-isolation @ 0f2603d+57b3fcc pushed.

Class: `cargo test` threads share process-global state. Specimen 1 = unwrapped fire_due_rotations test (explicit store paths = LOOKS hermetic) walks the FF ADR-0051 §2a loudness into ambient NotifStore::open()+EpochSource::load() → mints into a concurrent with_home window (psyrelay cafe:2) or, with no window, the RUNNER'S REAL live home (3 admin-rotation-incomplete rows + 3 real epochs found in live notifs.db, dismissed-not-deleted 2026-07-30). Specimen 2 = deliberately-inheritable canary swept into unrelated children by concurrent std Command spawns (bInheritHandles=TRUE, no handle list) — unfixable by locks.

**Why:** unit(Windows) intermittents at golden-green shas = check in-process shared-state class first; nextest process-per-test kills cross-test halves but NOT ambient-writes-to-real-home (only with_home wrap / de-ambienting does).
**How to apply:** RCA instrument = eprintln thread-name attribution in the shared resource (thread name == test name under libtest); repro loop = `cargo test -p spt-daemon --lib -- --skip seedmap --skip serveprobe --skip shellwake` (~50s/iter, reproduces under load). Unit lane now `cargo nextest run --workspace -E 'kind(lib) + kind(bin)'`. Follow-up REQ pending: no-ambient-home-resolution gate (recorded on #47). Product flag (todlando): asymmetric plumbing in admin_rotation_incomplete_loudness + KH 4.8 ambient-EpochSource surface. Related [[subnet-visibility-lease-regression]] [[stale-breadcrumb-tree-kill-class]].