From 2acf3ff368b4161ddc63ce65d387af8b139e2698 Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 00:15:55 -0700
Subject: [PATCH 01/16] test: add stock bash runner contract lane

---
 .github/workflows/ci.yml        | 12 +++++-
 bin/fm-test-run-stock-bash.sh   | 22 +++++++++++
 bin/fm-test-run.sh              | 22 ++++++++++-
 docs/fm-test-portable-shards.md |  8 ++++
 tests/fm-test-run.test.sh       | 66 +++++++++++++++++++++++++++++++++
 5 files changed, 126 insertions(+), 4 deletions(-)
 create mode 100755 bin/fm-test-run-stock-bash.sh

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8b81bf63767..6d78ed1aaa3 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -322,12 +322,12 @@ jobs:
           if-no-files-found: warn
 
   macos-stock-bash:
-    name: Stock macOS Bash snapshot compatibility
+    name: Stock macOS Bash runner compatibility
     runs-on: macos-latest
     timeout-minutes: 10
     steps:
       - uses: actions/checkout@v6
-      - name: Run snapshot consumers with stock Bash
+      - name: Run focused runner contract with stock Bash
         shell: /bin/bash {0}
         env:
           PATH: /bin:/usr/bin:/usr/sbin:/sbin:/usr/local/bin:/opt/homebrew/bin
@@ -348,6 +348,14 @@ jobs:
           done < "$shell_inventory"
           [ "$parse_fail" -eq 0 ] || { echo "::error::stock macOS Bash 3.2 parse sweep failed"; exit 1; }
 
+          runner_test_output=$(bin/fm-test-run-stock-bash.sh)
+          printf '%s\n' "$runner_test_output"
+          runner_test_count=$(printf '%s\n' "$runner_test_output" | grep -c '^ok - ')
+          [ "$runner_test_count" -eq 19 ] || {
+            echo "::error::expected 19 focused runner contract tests, got $runner_test_count"
+            exit 1
+          }
+
           snapshot_output=$(/bin/bash tests/fm-fleet-snapshot-view.test.sh)
           printf '%s\n' "$snapshot_output"
           snapshot_count=$(printf '%s\n' "$snapshot_output" | grep -c '^ok - ')
diff --git a/bin/fm-test-run-stock-bash.sh b/bin/fm-test-run-stock-bash.sh
new file mode 100755
index 00000000000..85f8a5e0b93
--- /dev/null
+++ b/bin/fm-test-run-stock-bash.sh
@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+# fm-test-run-stock-bash.sh - run the focused runner contract under stock
+# macOS Bash 3.2, with an explicit local skip when that interpreter is absent.
+set -eu
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+if [ ! -x /bin/bash ]; then
+  printf 'skip: stock Bash 3.2 unavailable (evidence: /bin/bash is missing)\n'
+  exit 0
+fi
+
+version=$(/bin/bash -c 'printf "%s" "$BASH_VERSION"')
+case "$version" in
+  3.2.*) ;;
+  *)
+    printf 'skip: stock Bash 3.2 unavailable (evidence: /bin/bash reports %s)\n' "$version"
+    exit 0
+    ;;
+esac
+
+exec /bin/bash "$ROOT/tests/fm-test-run.test.sh" "$@"
diff --git a/bin/fm-test-run.sh b/bin/fm-test-run.sh
index 0c24afd1628..cb5dcf0eba3 100755
--- a/bin/fm-test-run.sh
+++ b/bin/fm-test-run.sh
@@ -1504,7 +1504,21 @@ RUN_TMP=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run.XXXXXX")
 RECORDS="$RUN_TMP/records.tsv"
 FAMILIES_TSV="$RUN_TMP/families.tsv"
 : >"$RECORDS"
-trap 'rm -rf "$RUN_TMP"' EXIT
+
+cleanup_run() {
+  local rc=$? pid
+  trap - EXIT INT TERM HUP
+  for pid in $(jobs -p 2>/dev/null); do
+    kill "$pid" 2>/dev/null || true
+  done
+  rm -rf "$RUN_TMP"
+  exit "$rc"
+}
+
+trap cleanup_run EXIT
+trap 'exit 130' INT
+trap 'exit 143' TERM
+trap 'exit 129' HUP
 
 RUN_STARTED_ISO=$(now_iso)
 RUN_STARTED_MS=$(now_ms)
@@ -1746,8 +1760,12 @@ else
         FM_PROJECTS_OVERRIDE FM_CONFIG_OVERRIDE FM_BACKEND 2>/dev/null || true
       cd "$ROOT" || exit 1
       begin_ms=$(now_ms)
-      bash "$script" >"$work/output" 2>&1
+      bash "$script" >"$work/output" 2>&1 &
+      child_pid=$!
+      trap 'kill "$child_pid" 2>/dev/null || true; wait "$child_pid" 2>/dev/null || true; exit 143' INT TERM HUP
+      wait "$child_pid"
       rc=$?
+      trap - INT TERM HUP
       end_ms=$(now_ms)
       duration=$((end_ms - begin_ms))
       if [ "$duration" -lt 0 ]; then
diff --git a/docs/fm-test-portable-shards.md b/docs/fm-test-portable-shards.md
index 5268627c2a2..13a31c6b02c 100644
--- a/docs/fm-test-portable-shards.md
+++ b/docs/fm-test-portable-shards.md
@@ -96,6 +96,14 @@ It separately verifies that the portable serial CI shards are non-empty, disjoin
 
 Portable shards, each portable serial shard, and the Herdr lane upload runner-generated timing JSON.
 `bin/fm-test-run.sh --aggregate-json` creates the combined summary artifact.
+
+## Stock macOS Bash compatibility
+
+The CI job `macos-stock-bash` runs the focused `tests/fm-test-run.test.sh` contract under `/bin/bash` from the macOS image, covering parallel scheduling, result aggregation, quoting, private temporary paths, signal cleanup, and the GNU/BSD `stat` difference.
+The same job performs the repository-wide Bash parse sweep before the focused contract run.
+The compatibility boundary is stock macOS Bash 3.2.57 plus the commands explicitly required by the focused fixtures, including `mktemp`, `stat`, `sleep`, and `python3` for JSON assertions.
+The local reproduction command is `bin/fm-test-run-stock-bash.sh`.
+When Bash 3.2 is unavailable locally, the compatibility check may emit `skip: stock Bash 3.2 unavailable (evidence: <version or missing /bin/bash>)` and exit successfully; CI remains required on `macos-latest` and does not accept that skip.
 `.github/workflows/ci.yml` owns the exact artifact names and aggregation wiring.
 
 ## Local entry points
diff --git a/tests/fm-test-run.test.sh b/tests/fm-test-run.test.sh
index d2a33866a40..f0902439c00 100755
--- a/tests/fm-test-run.test.sh
+++ b/tests/fm-test-run.test.sh
@@ -256,6 +256,70 @@ assert "family" in doc["scripts"][0]
   pass "timing markers and JSON artifact are valid"
 }
 
+test_quoting_and_platform_temp_paths() {
+  local tmp repo fixture json out
+  tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-quoted.XXXXXX")
+  repo="$tmp/repo with spaces"
+  fixture="$repo/fixture with spaces.test.sh"
+  json="$tmp/artifact with spaces/timing.json"
+  mkdir -p "$repo/bin"
+  cp "$RUNNER" "$repo/bin/fm-test-run.sh"
+  chmod +x "$repo/bin/fm-test-run.sh"
+  cat >"$fixture" <<'SH'
+#!/usr/bin/env bash
+printf 'ok - quoted fixture\n'
+SH
+  chmod +x "$fixture"
+  out=$(cd "$repo" && ./bin/fm-test-run.sh --json "$json" "$fixture") \
+    || { rm -rf "$tmp"; fail "runner rejected a script or artifact path containing spaces"; }
+  assert_contains "$out" "FM_TEST_SUMMARY total=1 failed=0" "quoted path summary"
+  [ -f "$json" ] || { rm -rf "$tmp"; fail "quoted JSON path was not created"; }
+  rm -rf "$tmp"
+  pass "quoting, temporary paths, and platform stat fallback stay portable"
+}
+
+test_interrupt_cleans_parallel_worker() {
+  local tmp repo runner fixture evidence child_pid runner_pid rc
+  tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-signal.XXXXXX")
+  repo="$tmp/repo"
+  runner="$repo/bin/fm-test-run.sh"
+  fixture=tests/fm-brief.test.sh
+  evidence="$tmp/evidence"
+  mkdir -p "$repo/bin" "$repo/tests" "$evidence"
+  cp "$RUNNER" "$runner"
+  cat >"$repo/$fixture" <<'SH'
+#!/usr/bin/env bash
+printf '%s\n' "$$" >"$SCHED_EVIDENCE/child.pid"
+while :; do
+  sleep 1
+done
+SH
+  chmod +x "$runner" "$repo/$fixture"
+  SCHED_EVIDENCE="$evidence" "$runner" --jobs 2 "$fixture" >"$tmp/out" 2>"$tmp/err" &
+  runner_pid=$!
+  child_pid=
+  for _ in 1 2 3 4 5 6 7 8 9 10; do
+    if [ -s "$evidence/child.pid" ]; then
+      child_pid=$(cat "$evidence/child.pid")
+      break
+    fi
+    sleep 0.1
+  done
+  [ -n "$child_pid" ] || { kill "$runner_pid" 2>/dev/null || true; wait "$runner_pid" 2>/dev/null || true; rm -rf "$tmp"; fail "signal fixture never started"; }
+  kill -TERM "$runner_pid"
+  set +e
+  wait "$runner_pid"
+  rc=$?
+  set -e
+  [ "$rc" -eq 143 ] || { rm -rf "$tmp"; fail "runner TERM exit should be 143, got $rc"; }
+  if kill -0 "$child_pid" 2>/dev/null; then
+    rm -rf "$tmp"
+    fail "runner TERM left its worker child alive"
+  fi
+  rm -rf "$tmp"
+  pass "signals terminate parallel workers and clean private temporary state"
+}
+
 test_aggregate_exit_behavior() {
   local tmp pass_f fail_f rc
   tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-agg.XXXXXX")
@@ -847,6 +911,8 @@ test_changed_file_selection_is_conservative
 test_changed_dependency_selection_and_unmapped_failure
 test_empty_selection_emits_summary
 test_timing_markers_and_json
+test_quoting_and_platform_temp_paths
+test_interrupt_cleans_parallel_worker
 test_aggregate_exit_behavior
 test_gate_skip_accounting
 test_runtime_gate_required_and_optional_outcomes

From 2dcc637d3cb9eba797c2c04ff37c75d26f106fa9 Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 00:56:12 -0700
Subject: [PATCH 02/16] no-mistakes(review): fix: reap runner process trees
 synchronously

---
 .github/workflows/ci.yml  |  20 +-----
 bin/fm-test-run.sh        |  85 ++++++++++++++++++++---
 tests/fm-test-run.test.sh | 142 ++++++++++++++++++++++++++++++++++++--
 3 files changed, 215 insertions(+), 32 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6d78ed1aaa3..c06c9973ef7 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -351,24 +351,8 @@ jobs:
           runner_test_output=$(bin/fm-test-run-stock-bash.sh)
           printf '%s\n' "$runner_test_output"
           runner_test_count=$(printf '%s\n' "$runner_test_output" | grep -c '^ok - ')
-          [ "$runner_test_count" -eq 19 ] || {
-            echo "::error::expected 19 focused runner contract tests, got $runner_test_count"
-            exit 1
-          }
-
-          snapshot_output=$(/bin/bash tests/fm-fleet-snapshot-view.test.sh)
-          printf '%s\n' "$snapshot_output"
-          snapshot_count=$(printf '%s\n' "$snapshot_output" | grep -c '^ok - ')
-          [ "$snapshot_count" -eq 15 ] || {
-            echo "::error::expected 15 snapshot/fleet-view tests, got $snapshot_count"
-            exit 1
-          }
-
-          bearings_output=$(/bin/bash tests/fm-bearings-snapshot.test.sh)
-          printf '%s\n' "$bearings_output"
-          bearings_count=$(printf '%s\n' "$bearings_output" | grep -c '^ok - ')
-          [ "$bearings_count" -eq 41 ] || {
-            echo "::error::expected 41 Bearings tests, got $bearings_count"
+          [ "$runner_test_count" -eq 22 ] || {
+            echo "::error::expected 22 focused runner contract tests, got $runner_test_count"
             exit 1
           }
 
diff --git a/bin/fm-test-run.sh b/bin/fm-test-run.sh
index cb5dcf0eba3..3adfefcd5c3 100755
--- a/bin/fm-test-run.sh
+++ b/bin/fm-test-run.sh
@@ -1505,12 +1505,54 @@ RECORDS="$RUN_TMP/records.tsv"
 FAMILIES_TSV="$RUN_TMP/families.tsv"
 : >"$RECORDS"
 
+terminate_and_reap_process_tree() {
+  local root=$1 idx=0 parent children child seen pid
+  local -a process_tree_pids=()
+  if ! kill -STOP "$root" 2>/dev/null; then
+    wait "$root" 2>/dev/null || true
+    return
+  fi
+  process_tree_pids[0]=$root
+  while [ "$idx" -lt "${#process_tree_pids[@]}" ]; do
+    parent=${process_tree_pids[$idx]}
+    children=$(ps -eo pid=,ppid= 2>/dev/null | awk -v parent="$parent" '$2 == parent { print $1 }' || true)
+    while IFS= read -r child; do
+      [ -n "$child" ] || continue
+      seen=0
+      for pid in "${process_tree_pids[@]}"; do
+        if [ "$pid" = "$child" ]; then
+          seen=1
+          break
+        fi
+      done
+      if [ "$seen" -eq 0 ] && kill -STOP "$child" 2>/dev/null; then
+        process_tree_pids[${#process_tree_pids[@]}]=$child
+      fi
+    done <<<"$children"
+    idx=$((idx + 1))
+  done
+  for pid in "${process_tree_pids[@]}"; do
+    kill -TERM "$pid" 2>/dev/null || true
+  done
+  for pid in "${process_tree_pids[@]}"; do
+    kill -CONT "$pid" 2>/dev/null || true
+  done
+  wait "$root" 2>/dev/null || true
+  for pid in "${process_tree_pids[@]}"; do
+    while kill -0 "$pid" 2>/dev/null; do
+      sleep 0.01
+    done
+  done
+}
+
 cleanup_run() {
-  local rc=$? pid
+  local rc=$? pid cleanup_pids="$RUN_TMP/cleanup-pids"
   trap - EXIT INT TERM HUP
-  for pid in $(jobs -p 2>/dev/null); do
-    kill "$pid" 2>/dev/null || true
-  done
+  jobs -p >"$cleanup_pids" 2>/dev/null || true
+  while IFS= read -r pid; do
+    [ -n "$pid" ] || continue
+    terminate_and_reap_process_tree "$pid"
+  done <"$cleanup_pids"
   rm -rf "$RUN_TMP"
   exit "$rc"
 }
@@ -1637,7 +1679,7 @@ record_script_result() {
 
 run_one_serial() {
   local script=$1
-  local base family runtime requirement out begin_iso begin_ms end_ms end_iso duration rc
+  local base family runtime requirement out fifo begin_iso begin_ms end_ms end_iso duration rc child_pid tee_pid
   base=$(basename "$script")
   family=$(family_for_basename "$base")
   runtime=$(runtime_gate_for_basename "$base")
@@ -1650,10 +1692,16 @@ run_one_serial() {
     "$begin_iso" "$script" "$family" "$runtime" "$requirement"
 
   set +e
-  # Stream live output while retaining a copy for gate-skip detection.
-  # PIPESTATUS[0] is the test script; tee's exit is ignored for aggregate.
-  bash "$script" 2>&1 | tee "$out"
-  rc=${PIPESTATUS[0]}
+  fifo="$RUN_TMP/serial.$TOTAL.fifo"
+  mkfifo "$fifo"
+  tee "$out" <"$fifo" &
+  tee_pid=$!
+  bash "$script" >"$fifo" 2>&1 &
+  child_pid=$!
+  wait "$child_pid"
+  rc=$?
+  wait "$tee_pid" 2>/dev/null || true
+  rm -f "$fifo"
   set -e
   : "${rc:=1}"
 
@@ -1754,6 +1802,24 @@ else
       "$(now_iso)" "$script" "$family" "$runtime" "$requirement"
     (
       set +e
+      child_pid=
+      worker_signal_exit() {
+        local signal_rc=$1 pid signal_pids="$work/signal-pids"
+        trap - INT TERM HUP
+        if [ -n "$child_pid" ]; then
+          terminate_and_reap_process_tree "$child_pid"
+        else
+          jobs -p >"$signal_pids" 2>/dev/null || true
+          while IFS= read -r pid; do
+            [ -n "$pid" ] || continue
+            terminate_and_reap_process_tree "$pid"
+          done <"$signal_pids"
+        fi
+        exit "$signal_rc"
+      }
+      trap 'worker_signal_exit 130' INT
+      trap 'worker_signal_exit 143' TERM
+      trap 'worker_signal_exit 129' HUP
       export TMPDIR="$work/tmp"
       export TMP="$work/tmp"
       unset FM_HOME FM_STATE_OVERRIDE FM_DATA_OVERRIDE FM_ROOT_OVERRIDE \
@@ -1762,7 +1828,6 @@ else
       begin_ms=$(now_ms)
       bash "$script" >"$work/output" 2>&1 &
       child_pid=$!
-      trap 'kill "$child_pid" 2>/dev/null || true; wait "$child_pid" 2>/dev/null || true; exit 143' INT TERM HUP
       wait "$child_pid"
       rc=$?
       trap - INT TERM HUP
diff --git a/tests/fm-test-run.test.sh b/tests/fm-test-run.test.sh
index f0902439c00..a4340abe4b0 100755
--- a/tests/fm-test-run.test.sh
+++ b/tests/fm-test-run.test.sh
@@ -278,8 +278,78 @@ SH
   pass "quoting, temporary paths, and platform stat fallback stay portable"
 }
 
-test_interrupt_cleans_parallel_worker() {
-  local tmp repo runner fixture evidence child_pid runner_pid rc
+test_parallel_child_can_signal_immediately() {
+  local tmp repo runner fixture evidence child_pid rc
+  tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-pretrap.XXXXXX")
+  repo="$tmp/repo"
+  runner="$repo/bin/fm-test-run.sh"
+  fixture=tests/fm-brief.test.sh
+  evidence="$tmp/evidence"
+  mkdir -p "$repo/bin" "$repo/tests" "$evidence"
+  cp "$RUNNER" "$runner"
+  cat >"$repo/$fixture" <<'SH'
+#!/usr/bin/env bash
+printf '%s\n' "$$" >"$SCHED_EVIDENCE/child.pid"
+kill -TERM "$PPID"
+while :; do
+  sleep 1
+done
+SH
+  chmod +x "$runner" "$repo/$fixture"
+  set +e
+  SCHED_EVIDENCE="$evidence" "$runner" --jobs 2 "$fixture" >"$tmp/out" 2>"$tmp/err"
+  rc=$?
+  set -e
+  [ "$rc" -eq 1 ] || { rm -rf "$tmp"; fail "signaled parallel fixture should aggregate as failure, got $rc"; }
+  child_pid=$(cat "$evidence/child.pid" 2>/dev/null || true)
+  [ -n "$child_pid" ] || { rm -rf "$tmp"; fail "immediate-signal fixture never started"; }
+  if kill -0 "$child_pid" 2>/dev/null; then
+    rm -rf "$tmp"
+    fail "immediate child signal escaped worker cleanup"
+  fi
+  rm -rf "$tmp"
+  pass "parallel workers own signals before launching test children"
+}
+
+test_interrupt_cleans_serial_child() {
+  local tmp fixture child_pid runner_pid rc
+  tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-serial-signal.XXXXXX")
+  fixture="$tmp/serial.test.sh"
+  cat >"$fixture" <<'SH'
+#!/usr/bin/env bash
+printf '%s\n' "$$" >"$SCHED_EVIDENCE/child.pid"
+while :; do
+  sleep 1
+done
+SH
+  chmod +x "$fixture"
+  SCHED_EVIDENCE="$tmp" "$RUNNER" "$fixture" >"$tmp/out" 2>"$tmp/err" &
+  runner_pid=$!
+  child_pid=
+  for _ in 1 2 3 4 5 6 7 8 9 10; do
+    if [ -s "$tmp/child.pid" ]; then
+      child_pid=$(cat "$tmp/child.pid")
+      break
+    fi
+    sleep 0.1
+  done
+  [ -n "$child_pid" ] || { kill "$runner_pid" 2>/dev/null || true; wait "$runner_pid" 2>/dev/null || true; rm -rf "$tmp"; fail "serial signal fixture never started"; }
+  kill -TERM "$runner_pid"
+  set +e
+  wait "$runner_pid"
+  rc=$?
+  set -e
+  [ "$rc" -eq 143 ] || { rm -rf "$tmp"; fail "serial runner TERM exit should be 143, got $rc"; }
+  if kill -0 "$child_pid" 2>/dev/null; then
+    rm -rf "$tmp"
+    fail "runner TERM left its serial child alive"
+  fi
+  rm -rf "$tmp"
+  pass "signals terminate and reap serial test children"
+}
+
+test_interrupt_cleans_parallel_process_tree() {
+  local tmp repo runner fixture evidence child_pid descendant_pid runner_pid rc
   tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-signal.XXXXXX")
   repo="$tmp/repo"
   runner="$repo/bin/fm-test-run.sh"
@@ -290,6 +360,12 @@ test_interrupt_cleans_parallel_worker() {
   cat >"$repo/$fixture" <<'SH'
 #!/usr/bin/env bash
 printf '%s\n' "$$" >"$SCHED_EVIDENCE/child.pid"
+(
+  while :; do
+    sleep 1
+  done
+) &
+printf '%s\n' "$!" >"$SCHED_EVIDENCE/descendant.pid"
 while :; do
   sleep 1
 done
@@ -306,6 +382,8 @@ SH
     sleep 0.1
   done
   [ -n "$child_pid" ] || { kill "$runner_pid" 2>/dev/null || true; wait "$runner_pid" 2>/dev/null || true; rm -rf "$tmp"; fail "signal fixture never started"; }
+  descendant_pid=$(cat "$evidence/descendant.pid" 2>/dev/null || true)
+  [ -n "$descendant_pid" ] || { kill "$runner_pid" 2>/dev/null || true; wait "$runner_pid" 2>/dev/null || true; rm -rf "$tmp"; fail "descendant fixture never started"; }
   kill -TERM "$runner_pid"
   set +e
   wait "$runner_pid"
@@ -316,8 +394,61 @@ SH
     rm -rf "$tmp"
     fail "runner TERM left its worker child alive"
   fi
+  if kill -0 "$descendant_pid" 2>/dev/null; then
+    rm -rf "$tmp"
+    fail "runner TERM left its worker descendant alive"
+  fi
+  rm -rf "$tmp"
+  pass "signals terminate complete parallel worker process trees"
+}
+
+test_interrupt_waits_for_parallel_cleanup() {
+  local tmp repo runner fixture evidence child_pid runner_pid rc
+  tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-synchronous.XXXXXX")
+  repo="$tmp/repo"
+  runner="$repo/bin/fm-test-run.sh"
+  fixture=tests/fm-brief.test.sh
+  evidence="$tmp/evidence"
+  mkdir -p "$repo/bin" "$repo/tests" "$evidence"
+  cp "$RUNNER" "$runner"
+  cat >"$repo/$fixture" <<'SH'
+#!/usr/bin/env bash
+finish_cleanup() {
+  sleep 0.2
+  printf 'done\n' >"$SCHED_EVIDENCE/cleanup.done"
+  exit 0
+}
+trap finish_cleanup TERM
+printf '%s\n' "$$" >"$SCHED_EVIDENCE/child.pid"
+while :; do
+  sleep 1
+done
+SH
+  chmod +x "$runner" "$repo/$fixture"
+  SCHED_EVIDENCE="$evidence" "$runner" --jobs 2 "$fixture" >"$tmp/out" 2>"$tmp/err" &
+  runner_pid=$!
+  child_pid=
+  for _ in 1 2 3 4 5 6 7 8 9 10; do
+    if [ -s "$evidence/child.pid" ]; then
+      child_pid=$(cat "$evidence/child.pid")
+      break
+    fi
+    sleep 0.1
+  done
+  [ -n "$child_pid" ] || { kill "$runner_pid" 2>/dev/null || true; wait "$runner_pid" 2>/dev/null || true; rm -rf "$tmp"; fail "synchronous cleanup fixture never started"; }
+  kill -TERM "$runner_pid"
+  set +e
+  wait "$runner_pid"
+  rc=$?
+  set -e
+  [ "$rc" -eq 143 ] || { rm -rf "$tmp"; fail "synchronous cleanup TERM exit should be 143, got $rc"; }
+  [ -f "$evidence/cleanup.done" ] || { rm -rf "$tmp"; fail "runner returned before child cleanup completed"; }
+  if kill -0 "$child_pid" 2>/dev/null; then
+    rm -rf "$tmp"
+    fail "runner returned before the cleanup child exited"
+  fi
   rm -rf "$tmp"
-  pass "signals terminate parallel workers and clean private temporary state"
+  pass "signal handling completes child cleanup before returning"
 }
 
 test_aggregate_exit_behavior() {
@@ -912,7 +1043,10 @@ test_changed_dependency_selection_and_unmapped_failure
 test_empty_selection_emits_summary
 test_timing_markers_and_json
 test_quoting_and_platform_temp_paths
-test_interrupt_cleans_parallel_worker
+test_parallel_child_can_signal_immediately
+test_interrupt_cleans_serial_child
+test_interrupt_cleans_parallel_process_tree
+test_interrupt_waits_for_parallel_cleanup
 test_aggregate_exit_behavior
 test_gate_skip_accounting
 test_runtime_gate_required_and_optional_outcomes

From da876e2f4735ec4cba885b01fdaf6e636b99c28c Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 01:03:33 -0700
Subject: [PATCH 03/16] no-mistakes(review): fix: drain serial cleanup before
 reaping tee

---
 bin/fm-test-run.sh        | 31 ++++++++++++++++++++++++++-----
 tests/fm-test-run.test.sh | 20 +++++++++++++++++---
 2 files changed, 43 insertions(+), 8 deletions(-)

diff --git a/bin/fm-test-run.sh b/bin/fm-test-run.sh
index 3adfefcd5c3..51ccbeb7fea 100755
--- a/bin/fm-test-run.sh
+++ b/bin/fm-test-run.sh
@@ -1503,6 +1503,8 @@ fi
 RUN_TMP=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run.XXXXXX")
 RECORDS="$RUN_TMP/records.tsv"
 FAMILIES_TSV="$RUN_TMP/families.tsv"
+SERIAL_CHILD_PID=
+SERIAL_TEE_PID=
 : >"$RECORDS"
 
 terminate_and_reap_process_tree() {
@@ -1546,13 +1548,30 @@ terminate_and_reap_process_tree() {
 }
 
 cleanup_run() {
-  local rc=$? pid cleanup_pids="$RUN_TMP/cleanup-pids"
+  local rc=$? pid serial_child_owned=0 cleanup_pids="$RUN_TMP/cleanup-pids"
   trap - EXIT INT TERM HUP
   jobs -p >"$cleanup_pids" 2>/dev/null || true
+  if [ -n "$SERIAL_CHILD_PID" ]; then
+    terminate_and_reap_process_tree "$SERIAL_CHILD_PID"
+    serial_child_owned=1
+  fi
   while IFS= read -r pid; do
     [ -n "$pid" ] || continue
+    if [ "$pid" = "$SERIAL_CHILD_PID" ] || [ "$pid" = "$SERIAL_TEE_PID" ]; then
+      continue
+    fi
     terminate_and_reap_process_tree "$pid"
+    if [ -n "$SERIAL_TEE_PID" ]; then
+      serial_child_owned=1
+    fi
   done <"$cleanup_pids"
+  if [ -n "$SERIAL_TEE_PID" ]; then
+    if [ "$serial_child_owned" -eq 1 ]; then
+      wait "$SERIAL_TEE_PID" 2>/dev/null || true
+    else
+      terminate_and_reap_process_tree "$SERIAL_TEE_PID"
+    fi
+  fi
   rm -rf "$RUN_TMP"
   exit "$rc"
 }
@@ -1695,12 +1714,14 @@ run_one_serial() {
   fifo="$RUN_TMP/serial.$TOTAL.fifo"
   mkfifo "$fifo"
   tee "$out" <"$fifo" &
-  tee_pid=$!
+  SERIAL_TEE_PID=$!
   bash "$script" >"$fifo" 2>&1 &
-  child_pid=$!
-  wait "$child_pid"
+  SERIAL_CHILD_PID=$!
+  wait "$SERIAL_CHILD_PID"
   rc=$?
-  wait "$tee_pid" 2>/dev/null || true
+  wait "$SERIAL_TEE_PID" 2>/dev/null || true
+  SERIAL_CHILD_PID=
+  SERIAL_TEE_PID=
   rm -f "$fifo"
   set -e
   : "${rc:=1}"
diff --git a/tests/fm-test-run.test.sh b/tests/fm-test-run.test.sh
index a4340abe4b0..cdd26f5018c 100755
--- a/tests/fm-test-run.test.sh
+++ b/tests/fm-test-run.test.sh
@@ -311,12 +311,22 @@ SH
   pass "parallel workers own signals before launching test children"
 }
 
-test_interrupt_cleans_serial_child() {
+test_interrupt_drains_serial_cleanup() {
   local tmp fixture child_pid runner_pid rc
   tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-serial-signal.XXXXXX")
   fixture="$tmp/serial.test.sh"
   cat >"$fixture" <<'SH'
 #!/usr/bin/env bash
+set -e
+cleanup_done=
+cleanup() {
+  [ -z "$cleanup_done" ] || return
+  printf 'serial cleanup diagnostic\n'
+  printf 'released\n' >"$SCHED_EVIDENCE/resource.released"
+  cleanup_done=1
+}
+trap 'cleanup; exit 0' TERM
+trap cleanup EXIT
 printf '%s\n' "$$" >"$SCHED_EVIDENCE/child.pid"
 while :; do
   sleep 1
@@ -340,12 +350,16 @@ SH
   rc=$?
   set -e
   [ "$rc" -eq 143 ] || { rm -rf "$tmp"; fail "serial runner TERM exit should be 143, got $rc"; }
+  grep -Fq 'serial cleanup diagnostic' "$tmp/out" \
+    || { rm -rf "$tmp"; fail "serial cleanup diagnostic was not drained"; }
+  [ "$(cat "$tmp/resource.released" 2>/dev/null || true)" = "released" ] \
+    || { rm -rf "$tmp"; fail "serial cleanup did not release its resource"; }
   if kill -0 "$child_pid" 2>/dev/null; then
     rm -rf "$tmp"
     fail "runner TERM left its serial child alive"
   fi
   rm -rf "$tmp"
-  pass "signals terminate and reap serial test children"
+  pass "serial cleanup drains diagnostics before releasing tee"
 }
 
 test_interrupt_cleans_parallel_process_tree() {
@@ -1044,7 +1058,7 @@ test_empty_selection_emits_summary
 test_timing_markers_and_json
 test_quoting_and_platform_temp_paths
 test_parallel_child_can_signal_immediately
-test_interrupt_cleans_serial_child
+test_interrupt_drains_serial_cleanup
 test_interrupt_cleans_parallel_process_tree
 test_interrupt_waits_for_parallel_cleanup
 test_aggregate_exit_behavior

From 7dd8cbfd71d58903bc1c5ef03fcd2e8473415e5b Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 01:15:49 -0700
Subject: [PATCH 04/16] no-mistakes(document): Document stock Bash interpreter
 pinning

---
 .github/workflows/ci.yml        |  4 ++--
 bin/fm-test-run-stock-bash.sh   |  3 +++
 docs/fm-test-portable-shards.md |  3 ++-
 tests/fm-test-run.test.sh       | 23 +++++++++++++++++++++++
 4 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c06c9973ef7..48510d2c1f8 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -351,8 +351,8 @@ jobs:
           runner_test_output=$(bin/fm-test-run-stock-bash.sh)
           printf '%s\n' "$runner_test_output"
           runner_test_count=$(printf '%s\n' "$runner_test_output" | grep -c '^ok - ')
-          [ "$runner_test_count" -eq 22 ] || {
-            echo "::error::expected 22 focused runner contract tests, got $runner_test_count"
+          [ "$runner_test_count" -eq 23 ] || {
+            echo "::error::expected 23 focused runner contract tests, got $runner_test_count"
             exit 1
           }
 
diff --git a/bin/fm-test-run-stock-bash.sh b/bin/fm-test-run-stock-bash.sh
index 85f8a5e0b93..5e15247ef53 100755
--- a/bin/fm-test-run-stock-bash.sh
+++ b/bin/fm-test-run-stock-bash.sh
@@ -19,4 +19,7 @@ case "$version" in
     ;;
 esac
 
+export FM_STOCK_BASH_VERSION="$version"
+PATH=/bin:/usr/bin:/usr/sbin:/sbin:/usr/local/bin:/opt/homebrew/bin
+export PATH
 exec /bin/bash "$ROOT/tests/fm-test-run.test.sh" "$@"
diff --git a/docs/fm-test-portable-shards.md b/docs/fm-test-portable-shards.md
index 13a31c6b02c..1e285a6498a 100644
--- a/docs/fm-test-portable-shards.md
+++ b/docs/fm-test-portable-shards.md
@@ -101,7 +101,8 @@ Portable shards, each portable serial shard, and the Herdr lane upload runner-ge
 
 The CI job `macos-stock-bash` runs the focused `tests/fm-test-run.test.sh` contract under `/bin/bash` from the macOS image, covering parallel scheduling, result aggregation, quoting, private temporary paths, signal cleanup, and the GNU/BSD `stat` difference.
 The same job performs the repository-wide Bash parse sweep before the focused contract run.
-The compatibility boundary is stock macOS Bash 3.2.57 plus the commands explicitly required by the focused fixtures, including `mktemp`, `stat`, `sleep`, and `python3` for JSON assertions.
+The compatibility wrapper pins `PATH` so nested runner invocations also resolve `bash` to `/bin/bash`, and the focused contract verifies that interpreter identity.
+The compatibility boundary is stock macOS Bash 3.2.57 plus the commands explicitly required by the focused fixtures, including `awk`, `kill`, `mkfifo`, `mktemp`, `ps`, `sleep`, `stat`, `tee`, and `python3` for JSON assertions.
 The local reproduction command is `bin/fm-test-run-stock-bash.sh`.
 When Bash 3.2 is unavailable locally, the compatibility check may emit `skip: stock Bash 3.2 unavailable (evidence: <version or missing /bin/bash>)` and exit successfully; CI remains required on `macos-latest` and does not accept that skip.
 `.github/workflows/ci.yml` owns the exact artifact names and aggregation wiring.
diff --git a/tests/fm-test-run.test.sh b/tests/fm-test-run.test.sh
index cdd26f5018c..bbe7316db68 100755
--- a/tests/fm-test-run.test.sh
+++ b/tests/fm-test-run.test.sh
@@ -278,6 +278,28 @@ SH
   pass "quoting, temporary paths, and platform stat fallback stay portable"
 }
 
+test_stock_bash_wrapper_pins_nested_runner() {
+  local tmp fixture out
+  [ -n "${FM_STOCK_BASH_VERSION:-}" ] || return 0
+  tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-stock-bash.XXXXXX")
+  fixture="$tmp/interpreter.test.sh"
+  out="$tmp/out"
+  cat >"$fixture" <<'SH'
+#!/usr/bin/env bash
+if [ "$BASH_VERSION" != "$FM_STOCK_BASH_VERSION" ]; then
+  printf 'not ok - expected nested runner Bash %s, got %s\n' "$FM_STOCK_BASH_VERSION" "$BASH_VERSION"
+  exit 1
+fi
+printf 'ok - nested runner used stock Bash %s\n' "$BASH_VERSION"
+SH
+  chmod +x "$fixture"
+  "$RUNNER" "$fixture" >"$out" 2>&1 \
+    || { cat "$out"; rm -rf "$tmp"; fail "stock Bash wrapper did not pin the runner interpreter"; }
+  assert_contains "$(cat "$out")" "FM_TEST_SUMMARY total=1 failed=0" "stock Bash nested runner summary"
+  rm -rf "$tmp"
+  pass "stock Bash wrapper pins nested runner invocations to the verified interpreter"
+}
+
 test_parallel_child_can_signal_immediately() {
   local tmp repo runner fixture evidence child_pid rc
   tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-pretrap.XXXXXX")
@@ -1057,6 +1079,7 @@ test_changed_dependency_selection_and_unmapped_failure
 test_empty_selection_emits_summary
 test_timing_markers_and_json
 test_quoting_and_platform_temp_paths
+test_stock_bash_wrapper_pins_nested_runner
 test_parallel_child_can_signal_immediately
 test_interrupt_drains_serial_cleanup
 test_interrupt_cleans_parallel_process_tree

From 9d3cd1a1dc16404c4824f3b3dfec02d2d3edb045 Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 01:22:29 -0700
Subject: [PATCH 05/16] no-mistakes(lint): Captain: suppress indirect trap
 callback lint warnings

---
 bin/fm-test-run.sh | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/bin/fm-test-run.sh b/bin/fm-test-run.sh
index 51ccbeb7fea..9ec906ddc6e 100755
--- a/bin/fm-test-run.sh
+++ b/bin/fm-test-run.sh
@@ -1507,6 +1507,7 @@ SERIAL_CHILD_PID=
 SERIAL_TEE_PID=
 : >"$RECORDS"
 
+# shellcheck disable=SC2329 # Invoked indirectly by the cleanup and worker signal traps.
 terminate_and_reap_process_tree() {
   local root=$1 idx=0 parent children child seen pid
   local -a process_tree_pids=()
@@ -1547,6 +1548,7 @@ terminate_and_reap_process_tree() {
   done
 }
 
+# shellcheck disable=SC2329 # Registered by the EXIT and signal traps below.
 cleanup_run() {
   local rc=$? pid serial_child_owned=0 cleanup_pids="$RUN_TMP/cleanup-pids"
   trap - EXIT INT TERM HUP
@@ -1824,6 +1826,7 @@ else
     (
       set +e
       child_pid=
+      # shellcheck disable=SC2329 # Registered by the worker signal traps below.
       worker_signal_exit() {
         local signal_rc=$1 pid signal_pids="$work/signal-pids"
         trap - INT TERM HUP

From 42b1e2ae81d3df43c426bf825ff445026ec7c658 Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 02:45:48 -0700
Subject: [PATCH 06/16] no-mistakes(review): Bound signal cleanup and remove
 stale jq prerequisite

---
 .github/workflows/ci.yml  |  1 -
 bin/fm-test-run.sh        | 22 +++++++++++++++++++++-
 tests/fm-test-run.test.sh | 30 +++++++++++++++++++++++-------
 3 files changed, 44 insertions(+), 9 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 48510d2c1f8..2e8b4233fee 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -338,7 +338,6 @@ jobs:
             *) echo "::error::expected stock macOS Bash 3.2.57, got $BASH_VERSION"; exit 1 ;;
           esac
           /bin/bash --version | head -1
-          command -v jq >/dev/null || { echo "::error::jq is required"; exit 1; }
 
           shell_inventory="$RUNNER_TEMP/fm-shell-inventory"
           bin/fm-lint.sh --list-files > "$shell_inventory"
diff --git a/bin/fm-test-run.sh b/bin/fm-test-run.sh
index 9ec906ddc6e..1723b7edf18 100755
--- a/bin/fm-test-run.sh
+++ b/bin/fm-test-run.sh
@@ -1509,7 +1509,7 @@ SERIAL_TEE_PID=
 
 # shellcheck disable=SC2329 # Invoked indirectly by the cleanup and worker signal traps.
 terminate_and_reap_process_tree() {
-  local root=$1 idx=0 parent children child seen pid
+  local root=$1 idx=0 parent children child seen pid grace=0 running state
   local -a process_tree_pids=()
   if ! kill -STOP "$root" 2>/dev/null; then
     wait "$root" 2>/dev/null || true
@@ -1540,6 +1540,26 @@ terminate_and_reap_process_tree() {
   for pid in "${process_tree_pids[@]}"; do
     kill -CONT "$pid" 2>/dev/null || true
   done
+  while [ "$grace" -lt 100 ]; do
+    running=0
+    for pid in "${process_tree_pids[@]}"; do
+      state=$(ps -o stat= -p "$pid" 2>/dev/null | awk 'NR == 1 { print $1 }' || true)
+      case "$state" in
+        ""|Z*) ;;
+        *) running=1; break ;;
+      esac
+    done
+    [ "$running" -eq 1 ] || break
+    sleep 0.01
+    grace=$((grace + 1))
+  done
+  for pid in "${process_tree_pids[@]}"; do
+    state=$(ps -o stat= -p "$pid" 2>/dev/null | awk 'NR == 1 { print $1 }' || true)
+    case "$state" in
+      ""|Z*) ;;
+      *) kill -KILL "$pid" 2>/dev/null || true ;;
+    esac
+  done
   wait "$root" 2>/dev/null || true
   for pid in "${process_tree_pids[@]}"; do
     while kill -0 "$pid" 2>/dev/null; do
diff --git a/tests/fm-test-run.test.sh b/tests/fm-test-run.test.sh
index bbe7316db68..810875e4b18 100755
--- a/tests/fm-test-run.test.sh
+++ b/tests/fm-test-run.test.sh
@@ -385,23 +385,28 @@ SH
 }
 
 test_interrupt_cleans_parallel_process_tree() {
-  local tmp repo runner fixture evidence child_pid descendant_pid runner_pid rc
+  local tmp repo runner fixture evidence child_pid descendant_pid runner_pid waited rc
   tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-signal.XXXXXX")
   repo="$tmp/repo"
   runner="$repo/bin/fm-test-run.sh"
   fixture=tests/fm-brief.test.sh
   evidence="$tmp/evidence"
   mkdir -p "$repo/bin" "$repo/tests" "$evidence"
+  mkfifo "$evidence/term-ignored"
   cp "$RUNNER" "$runner"
   cat >"$repo/$fixture" <<'SH'
 #!/usr/bin/env bash
-printf '%s\n' "$$" >"$SCHED_EVIDENCE/child.pid"
 (
-  while :; do
-    sleep 1
-  done
+  trap '' TERM
+  : >"$SCHED_EVIDENCE/descendant.ready"
+  IFS= read -r _ <"$SCHED_EVIDENCE/term-ignored"
 ) &
-printf '%s\n' "$!" >"$SCHED_EVIDENCE/descendant.pid"
+descendant_pid=$!
+while [ ! -e "$SCHED_EVIDENCE/descendant.ready" ]; do
+  sleep 0.01
+done
+printf '%s\n' "$$" >"$SCHED_EVIDENCE/child.pid"
+printf '%s\n' "$descendant_pid" >"$SCHED_EVIDENCE/descendant.pid"
 while :; do
   sleep 1
 done
@@ -421,6 +426,17 @@ SH
   descendant_pid=$(cat "$evidence/descendant.pid" 2>/dev/null || true)
   [ -n "$descendant_pid" ] || { kill "$runner_pid" 2>/dev/null || true; wait "$runner_pid" 2>/dev/null || true; rm -rf "$tmp"; fail "descendant fixture never started"; }
   kill -TERM "$runner_pid"
+  waited=0
+  while kill -0 "$runner_pid" 2>/dev/null && [ "$waited" -lt 50 ]; do
+    sleep 0.1
+    waited=$((waited + 1))
+  done
+  if kill -0 "$runner_pid" 2>/dev/null; then
+    kill -KILL "$runner_pid" "$child_pid" "$descendant_pid" 2>/dev/null || true
+    wait "$runner_pid" 2>/dev/null || true
+    rm -rf "$tmp"
+    fail "runner TERM hung on a TERM-ignoring descendant"
+  fi
   set +e
   wait "$runner_pid"
   rc=$?
@@ -435,7 +451,7 @@ SH
     fail "runner TERM left its worker descendant alive"
   fi
   rm -rf "$tmp"
-  pass "signals terminate complete parallel worker process trees"
+  pass "signals escalate and terminate complete parallel worker process trees"
 }
 
 test_interrupt_waits_for_parallel_cleanup() {

From f6bf7641bf217a937cb13b8e890875f20c90f1b3 Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 02:53:45 -0700
Subject: [PATCH 07/16] no-mistakes(document): Document stock Bash runner
 wrapper

---
 docs/scripts.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/docs/scripts.md b/docs/scripts.md
index a48fac9db5f..339840774cd 100644
--- a/docs/scripts.md
+++ b/docs/scripts.md
@@ -31,6 +31,7 @@ The shared no-mistakes gate refusal for fleet lifecycle entrypoints is summarize
 | `fm-install-treehouse.sh`| Install CI's exact-version Treehouse pin for real-Herdr E2E that needs spawn worktrees |
 | `fm-herdr-ci-cleanup.sh` | Snapshot and tear down only job-owned `fm-lab-*` sessions in the Herdr CI lane       |
 | `fm-test-run.sh`         | Behavior-test runner: selection, portable lanes, declarative runtime gates, proven-isolated `--jobs`, coverage guard, timing/JSON |
+| `fm-test-run-stock-bash.sh` | Run the focused runner contract under stock macOS Bash 3.2, or emit explicit local skip evidence |
 | `fm-test-isolation-proof.sh` | Concurrent isolation proof and proven-isolated candidate set owner |
 | `fm-ensure-agents-md.sh` | Ensure a project's real `AGENTS.md`, its `CLAUDE.md` symlink, and the canonical self-governance section |
 | `fm-guard.sh`            | Warn on primary-checkout tangles, pending queued wakes, and stale watcher liveness   |

From 1fc3208a53921088e43945699fc7e612e6c7dcdf Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 03:20:32 -0700
Subject: [PATCH 08/16] no-mistakes(review): Bound signal escalation and
 descendant reaping

---
 bin/fm-test-run.sh | 37 ++++++++++++++++++++++++++++++++++---
 1 file changed, 34 insertions(+), 3 deletions(-)

diff --git a/bin/fm-test-run.sh b/bin/fm-test-run.sh
index 1723b7edf18..f9d2ba8430d 100755
--- a/bin/fm-test-run.sh
+++ b/bin/fm-test-run.sh
@@ -1553,6 +1553,28 @@ terminate_and_reap_process_tree() {
     sleep 0.01
     grace=$((grace + 1))
   done
+  for pid in "${process_tree_pids[@]}"; do
+    kill -STOP "$pid" 2>/dev/null || true
+  done
+  idx=0
+  while [ "$idx" -lt "${#process_tree_pids[@]}" ]; do
+    parent=${process_tree_pids[$idx]}
+    children=$(ps -eo pid=,ppid= 2>/dev/null | awk -v parent="$parent" '$2 == parent { print $1 }' || true)
+    while IFS= read -r child; do
+      [ -n "$child" ] || continue
+      seen=0
+      for pid in "${process_tree_pids[@]}"; do
+        if [ "$pid" = "$child" ]; then
+          seen=1
+          break
+        fi
+      done
+      if [ "$seen" -eq 0 ] && kill -STOP "$child" 2>/dev/null; then
+        process_tree_pids[${#process_tree_pids[@]}]=$child
+      fi
+    done <<<"$children"
+    idx=$((idx + 1))
+  done
   for pid in "${process_tree_pids[@]}"; do
     state=$(ps -o stat= -p "$pid" 2>/dev/null | awk 'NR == 1 { print $1 }' || true)
     case "$state" in
@@ -1561,10 +1583,19 @@ terminate_and_reap_process_tree() {
     esac
   done
   wait "$root" 2>/dev/null || true
-  for pid in "${process_tree_pids[@]}"; do
-    while kill -0 "$pid" 2>/dev/null; do
-      sleep 0.01
+  grace=0
+  while [ "$grace" -lt 100 ]; do
+    running=0
+    for pid in "${process_tree_pids[@]}"; do
+      state=$(ps -o stat= -p "$pid" 2>/dev/null | awk 'NR == 1 { print $1 }' || true)
+      case "$state" in
+        ""|Z*) ;;
+        *) running=1; break ;;
+      esac
     done
+    [ "$running" -eq 1 ] || break
+    sleep 0.01
+    grace=$((grace + 1))
   done
 }
 

From 7536bf664c35644e1744eb2350a457bae9290b02 Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 03:28:09 -0700
Subject: [PATCH 09/16] no-mistakes(review): Isolate test cleanup in bounded
 process groups

---
 bin/fm-test-run.sh | 51 +++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 48 insertions(+), 3 deletions(-)

diff --git a/bin/fm-test-run.sh b/bin/fm-test-run.sh
index f9d2ba8430d..1c2fec03287 100755
--- a/bin/fm-test-run.sh
+++ b/bin/fm-test-run.sh
@@ -1599,13 +1599,50 @@ terminate_and_reap_process_tree() {
   done
 }
 
+process_group_has_running_members() {
+  ps -eo pgid=,stat= 2>/dev/null \
+    | awk -v group="$1" '$1 == group && $2 !~ /^Z/ { found=1; exit } END { exit !found }'
+}
+
+terminate_and_reap_process_group() {
+  local group=$1 grace=0
+  if ! kill -STOP -- "-$group" 2>/dev/null; then
+    wait "$group" 2>/dev/null || true
+    return
+  fi
+  kill -TERM -- "-$group" 2>/dev/null || true
+  kill -CONT -- "-$group" 2>/dev/null || true
+  while [ "$grace" -lt 100 ] && process_group_has_running_members "$group"; do
+    sleep 0.01
+    grace=$((grace + 1))
+  done
+  kill -STOP -- "-$group" 2>/dev/null || true
+  kill -KILL -- "-$group" 2>/dev/null || true
+  wait "$group" 2>/dev/null || true
+  grace=0
+  while [ "$grace" -lt 100 ] && process_group_has_running_members "$group"; do
+    sleep 0.01
+    grace=$((grace + 1))
+  done
+}
+
+terminate_and_reap_background_job() {
+  local pid=$1 group
+  group=$(ps -o pgid= -p "$pid" 2>/dev/null | awk 'NR == 1 { gsub(/[[:space:]]/, "", $1); print $1 }' || true)
+  if [ "$group" = "$pid" ]; then
+    terminate_and_reap_process_group "$group"
+  else
+    terminate_and_reap_process_tree "$pid"
+  fi
+}
+
 # shellcheck disable=SC2329 # Registered by the EXIT and signal traps below.
 cleanup_run() {
   local rc=$? pid serial_child_owned=0 cleanup_pids="$RUN_TMP/cleanup-pids"
   trap - EXIT INT TERM HUP
   jobs -p >"$cleanup_pids" 2>/dev/null || true
   if [ -n "$SERIAL_CHILD_PID" ]; then
-    terminate_and_reap_process_tree "$SERIAL_CHILD_PID"
+    terminate_and_reap_process_group "$SERIAL_CHILD_PID"
     serial_child_owned=1
   fi
   while IFS= read -r pid; do
@@ -1613,7 +1650,7 @@ cleanup_run() {
     if [ "$pid" = "$SERIAL_CHILD_PID" ] || [ "$pid" = "$SERIAL_TEE_PID" ]; then
       continue
     fi
-    terminate_and_reap_process_tree "$pid"
+    terminate_and_reap_background_job "$pid"
     if [ -n "$SERIAL_TEE_PID" ]; then
       serial_child_owned=1
     fi
@@ -1751,7 +1788,7 @@ record_script_result() {
 
 run_one_serial() {
   local script=$1
-  local base family runtime requirement out fifo begin_iso begin_ms end_ms end_iso duration rc child_pid tee_pid
+  local base family runtime requirement out fifo begin_iso begin_ms end_ms end_iso duration rc child_pid tee_pid monitor_mode=
   base=$(basename "$script")
   family=$(family_for_basename "$base")
   runtime=$(runtime_gate_for_basename "$base")
@@ -1768,8 +1805,11 @@ run_one_serial() {
   mkfifo "$fifo"
   tee "$out" <"$fifo" &
   SERIAL_TEE_PID=$!
+  case $- in *m*) monitor_mode=1 ;; esac
+  set -m
   bash "$script" >"$fifo" 2>&1 &
   SERIAL_CHILD_PID=$!
+  [ -n "$monitor_mode" ] || set +m
   wait "$SERIAL_CHILD_PID"
   rc=$?
   wait "$SERIAL_TEE_PID" 2>/dev/null || true
@@ -1874,7 +1914,11 @@ else
     requirement=$(runtime_gate_requirement "$runtime")
     printf 'FM_TEST_BEGIN %s %s family=%s runtime_gate=%s gate_requirement=%s\n' \
       "$(now_iso)" "$script" "$family" "$runtime" "$requirement"
+    monitor_mode=
+    case $- in *m*) monitor_mode=1 ;; esac
+    set -m
     (
+      set +m
       set +e
       child_pid=
       # shellcheck disable=SC2329 # Registered by the worker signal traps below.
@@ -1916,6 +1960,7 @@ else
       exit 0
     ) &
     WORKER_PIDS[worker_n]=$!
+    [ -n "$monitor_mode" ] || set +m
     WORKER_IDX[worker_n]=$worker_n
     WORKER_SCRIPTS[worker_n]=$script
     active_workers=$((active_workers + 1))

From 0557c3bf571dc91bf2124ad25c9988a78f7688a6 Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 03:32:34 -0700
Subject: [PATCH 10/16] no-mistakes(review): Drain completed parallel worker
 process groups

---
 bin/fm-test-run.sh | 1 +
 1 file changed, 1 insertion(+)

diff --git a/bin/fm-test-run.sh b/bin/fm-test-run.sh
index 1c2fec03287..53c26b758d5 100755
--- a/bin/fm-test-run.sh
+++ b/bin/fm-test-run.sh
@@ -1853,6 +1853,7 @@ else
     active_workers=$((active_workers - 1))
     set +e
     wait "$pid"
+    terminate_and_reap_process_group "$pid"
     set -e
     work="$RUN_TMP/w$idx"
     rc=$(cat "$work/exit" 2>/dev/null || echo 1)

From 3573f61b819dbcfe296c1eb3bc3d702459478e87 Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 03:39:55 -0700
Subject: [PATCH 11/16] no-mistakes(document): Confirm stock Bash runner
 documentation accuracy

---
 tests/fm-test-run.test.sh | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/tests/fm-test-run.test.sh b/tests/fm-test-run.test.sh
index 810875e4b18..15765b20809 100755
--- a/tests/fm-test-run.test.sh
+++ b/tests/fm-test-run.test.sh
@@ -503,6 +503,44 @@ SH
   pass "signal handling completes child cleanup before returning"
 }
 
+test_completed_parallel_worker_drains_process_group() {
+  local tmp repo runner fixture evidence descendant_pid state rc
+  tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-completed-worker.XXXXXX")
+  repo="$tmp/repo"
+  runner="$repo/bin/fm-test-run.sh"
+  fixture=tests/fm-brief.test.sh
+  evidence="$tmp/evidence"
+  mkdir -p "$repo/bin" "$repo/tests" "$evidence"
+  cp "$RUNNER" "$runner"
+  cat >"$repo/$fixture" <<'SH'
+#!/usr/bin/env bash
+bash -c 'trap "" HUP TERM; while :; do sleep 1; done' &
+descendant_pid=$!
+printf '%s\n' "$descendant_pid" >"$SCHED_EVIDENCE/descendant.pid"
+printf 'ok - fixture completed while descendant remained active\n'
+SH
+  chmod +x "$runner" "$repo/$fixture"
+  set +e
+  SCHED_EVIDENCE="$evidence" "$runner" --jobs 2 "$fixture" >"$tmp/out" 2>"$tmp/err"
+  rc=$?
+  set -e
+  [ "$rc" -eq 0 ] || { cat "$tmp/out" "$tmp/err"; rm -rf "$tmp"; fail "completed parallel fixture should pass, got $rc"; }
+  assert_contains "$(cat "$tmp/out")" "FM_TEST_SUMMARY total=1 failed=0" "completed parallel fixture summary"
+  descendant_pid=$(cat "$evidence/descendant.pid" 2>/dev/null || true)
+  [ -n "$descendant_pid" ] || { rm -rf "$tmp"; fail "completed parallel fixture did not record its descendant"; }
+  state=$(ps -o stat= -p "$descendant_pid" 2>/dev/null | awk 'NR == 1 { print $1 }' || true)
+  case "$state" in
+    ""|Z*) ;;
+    *)
+      kill -KILL "$descendant_pid" 2>/dev/null || true
+      rm -rf "$tmp"
+      fail "completed parallel worker left a live descendant behind (pid=$descendant_pid state=$state)"
+      ;;
+  esac
+  rm -rf "$tmp"
+  pass "completed parallel workers drain their remaining process groups"
+}
+
 test_aggregate_exit_behavior() {
   local tmp pass_f fail_f rc
   tmp=$(mktemp -d "${TMPDIR:-/tmp}/fm-test-run-agg.XXXXXX")
@@ -1100,6 +1138,7 @@ test_parallel_child_can_signal_immediately
 test_interrupt_drains_serial_cleanup
 test_interrupt_cleans_parallel_process_tree
 test_interrupt_waits_for_parallel_cleanup
+test_completed_parallel_worker_drains_process_group
 test_aggregate_exit_behavior
 test_gate_skip_accounting
 test_runtime_gate_required_and_optional_outcomes

From 0594be1072fc42db99c151861894b09de9212bd6 Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 03:52:20 -0700
Subject: [PATCH 12/16] no-mistakes(review): Suppress trap-only background
 reaper ShellCheck warning

---
 bin/fm-test-run.sh | 1 +
 1 file changed, 1 insertion(+)

diff --git a/bin/fm-test-run.sh b/bin/fm-test-run.sh
index 53c26b758d5..825f5d97cce 100755
--- a/bin/fm-test-run.sh
+++ b/bin/fm-test-run.sh
@@ -1626,6 +1626,7 @@ terminate_and_reap_process_group() {
   done
 }
 
+# shellcheck disable=SC2329 # Invoked indirectly by the EXIT and signal traps through cleanup_run.
 terminate_and_reap_background_job() {
   local pid=$1 group
   group=$(ps -o pgid= -p "$pid" 2>/dev/null | awk 'NR == 1 { gsub(/[[:space:]]/, "", $1); print $1 }' || true)

From 53871337081f62852a9943da3abe46862e3131dd Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 04:02:30 -0700
Subject: [PATCH 13/16] no-mistakes(document): Correct focused CI test count

---
 .github/workflows/ci.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2e8b4233fee..e7658d82c59 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -350,8 +350,8 @@ jobs:
           runner_test_output=$(bin/fm-test-run-stock-bash.sh)
           printf '%s\n' "$runner_test_output"
           runner_test_count=$(printf '%s\n' "$runner_test_output" | grep -c '^ok - ')
-          [ "$runner_test_count" -eq 23 ] || {
-            echo "::error::expected 23 focused runner contract tests, got $runner_test_count"
+          [ "$runner_test_count" -eq 24 ] || {
+            echo "::error::expected 24 focused runner contract tests, got $runner_test_count"
             exit 1
           }
 

From 774ee111276523b323a8c7e33c40b8bec5c20a13 Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 04:21:40 -0700
Subject: [PATCH 14/16] no-mistakes(review): Restore stock Bash snapshot
 runtime coverage

---
 .github/workflows/ci.yml | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e7658d82c59..444ca1f5502 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -347,11 +347,27 @@ jobs:
           done < "$shell_inventory"
           [ "$parse_fail" -eq 0 ] || { echo "::error::stock macOS Bash 3.2 parse sweep failed"; exit 1; }
 
+          snapshot_output=$(/bin/bash tests/fm-fleet-snapshot-view.test.sh)
+          printf '%s\n' "$snapshot_output"
+          snapshot_count=$(printf '%s\n' "$snapshot_output" | grep -c '^ok - ')
+          [ "$snapshot_count" -eq 15 ] || {
+            echo "::error::expected 15 snapshot/fleet-view tests, got $snapshot_count"
+            exit 1
+          }
+
+          bearings_output=$(/bin/bash tests/fm-bearings-snapshot.test.sh)
+          printf '%s\n' "$bearings_output"
+          bearings_count=$(printf '%s\n' "$bearings_output" | grep -c '^ok - ')
+          [ "$bearings_count" -eq 41 ] || {
+            echo "::error::expected 41 Bearings tests, got $bearings_count"
+            exit 1
+          }
+
           runner_test_output=$(bin/fm-test-run-stock-bash.sh)
           printf '%s\n' "$runner_test_output"
           runner_test_count=$(printf '%s\n' "$runner_test_output" | grep -c '^ok - ')
-          [ "$runner_test_count" -eq 24 ] || {
-            echo "::error::expected 24 focused runner contract tests, got $runner_test_count"
+          [ "$runner_test_count" -eq 27 ] || {
+            echo "::error::expected 27 focused runner contract tests, got $runner_test_count"
             exit 1
           }
 

From 6ecb585747365adde0a03e0276cf56f29f1e2451 Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 04:33:54 -0700
Subject: [PATCH 15/16] no-mistakes(document): Document stock Bash snapshot
 runtime coverage

---
 docs/fm-test-portable-shards.md | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/docs/fm-test-portable-shards.md b/docs/fm-test-portable-shards.md
index 1e285a6498a..dd49c7e8f4a 100644
--- a/docs/fm-test-portable-shards.md
+++ b/docs/fm-test-portable-shards.md
@@ -99,13 +99,14 @@ Portable shards, each portable serial shard, and the Herdr lane upload runner-ge
 
 ## Stock macOS Bash compatibility
 
-The CI job `macos-stock-bash` runs the focused `tests/fm-test-run.test.sh` contract under `/bin/bash` from the macOS image, covering parallel scheduling, result aggregation, quoting, private temporary paths, signal cleanup, and the GNU/BSD `stat` difference.
-The same job performs the repository-wide Bash parse sweep before the focused contract run.
+The CI job `macos-stock-bash` runs `tests/fm-fleet-snapshot-view.test.sh`, `tests/fm-bearings-snapshot.test.sh`, and the focused `tests/fm-test-run.test.sh` contract under `/bin/bash` from the macOS image.
+The snapshot suites preserve stock-Bash runtime coverage for fleet snapshot/view and Bearings rendering, while the focused runner contract covers parallel scheduling, result aggregation, quoting, private temporary paths, signal cleanup, and the GNU/BSD `stat` difference.
+The same job performs the repository-wide Bash parse sweep before the runtime test suites.
 The compatibility wrapper pins `PATH` so nested runner invocations also resolve `bash` to `/bin/bash`, and the focused contract verifies that interpreter identity.
-The compatibility boundary is stock macOS Bash 3.2.57 plus the commands explicitly required by the focused fixtures, including `awk`, `kill`, `mkfifo`, `mktemp`, `ps`, `sleep`, `stat`, `tee`, and `python3` for JSON assertions.
-The local reproduction command is `bin/fm-test-run-stock-bash.sh`.
-When Bash 3.2 is unavailable locally, the compatibility check may emit `skip: stock Bash 3.2 unavailable (evidence: <version or missing /bin/bash>)` and exit successfully; CI remains required on `macos-latest` and does not accept that skip.
-`.github/workflows/ci.yml` owns the exact artifact names and aggregation wiring.
+The focused runner compatibility boundary is stock macOS Bash 3.2.57 plus the commands explicitly required by its fixtures, including `awk`, `kill`, `mkfifo`, `mktemp`, `ps`, `sleep`, `stat`, `tee`, and `python3` for JSON assertions.
+The focused runner contract's local reproduction command is `bin/fm-test-run-stock-bash.sh`.
+When Bash 3.2 is unavailable locally, that wrapper may emit `skip: stock Bash 3.2 unavailable (evidence: <version or missing /bin/bash>)` and exit successfully; CI remains required on `macos-latest` and does not accept that skip.
+`.github/workflows/ci.yml` owns the exact CI command sequence, expected test counts, artifact names, and aggregation wiring.
 
 ## Local entry points
 

From fd944d8e04d7809141f8c2d1911460ccbefdb22b Mon Sep 17 00:00:00 2001
From: QuinnBot <quinnbot@proton.me>
Date: Thu, 6 Aug 2026 04:38:35 -0700
Subject: [PATCH 16/16] no-mistakes(lint): Remove unused serial runner tee PID
 declaration

---
 bin/fm-test-run.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bin/fm-test-run.sh b/bin/fm-test-run.sh
index 825f5d97cce..7c37b6fc290 100755
--- a/bin/fm-test-run.sh
+++ b/bin/fm-test-run.sh
@@ -1789,7 +1789,7 @@ record_script_result() {
 
 run_one_serial() {
   local script=$1
-  local base family runtime requirement out fifo begin_iso begin_ms end_ms end_iso duration rc child_pid tee_pid monitor_mode=
+  local base family runtime requirement out fifo begin_iso begin_ms end_ms end_iso duration rc child_pid monitor_mode=
   base=$(basename "$script")
   family=$(family_for_basename "$base")
   runtime=$(runtime_gate_for_basename "$base")