diff --git a/lib/clean/caches.sh b/lib/clean/caches.sh
index f7b4e1c..72892ce 100644
--- a/lib/clean/caches.sh
+++ b/lib/clean/caches.sh
@@ -1,6 +1,9 @@
 #!/bin/bash
 # Cache Cleanup Module
 set -euo pipefail
+
+# shellcheck disable=SC1091
+source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/purge_shared.sh"
 # Preflight TCC prompts once to avoid mid-run interruptions.
 check_tcc_permissions() {
     [[ -t 1 ]] || return 0
@@ -88,154 +91,138 @@ clean_service_worker_cache() {
         fi
     fi
 }
-# Next.js/Python project caches with tight scan bounds and timeouts.
-clean_project_caches() {
-    stop_inline_spinner 2> /dev/null || true
-    # Fast pre-check before scanning the whole home dir.
-    local has_dev_projects=false
-    local -a common_dev_dirs=(
-        "$HOME/Code"
-        "$HOME/Projects"
-        "$HOME/workspace"
-        "$HOME/github"
-        "$HOME/dev"
-        "$HOME/work"
-        "$HOME/src"
-        "$HOME/repos"
-        "$HOME/Developer"
-        "$HOME/Development"
-        "$HOME/www"
-        "$HOME/golang"
-        "$HOME/go"
-        "$HOME/rust"
-        "$HOME/python"
-        "$HOME/ruby"
-        "$HOME/java"
-        "$HOME/dotnet"
-        "$HOME/node"
-    )
-    for dir in "${common_dev_dirs[@]}"; do
-        if [[ -d "$dir" ]]; then
-            has_dev_projects=true
-            break
+# Check whether a directory looks like a project container.
+project_cache_has_indicators() {
+    local dir="$1"
+    local max_depth="${2:-5}"
+    local indicator_timeout="${MOLE_PROJECT_CACHE_DISCOVERY_TIMEOUT:-2}"
+    [[ -d "$dir" ]] || return 1
+
+    local -a find_args=("$dir" "-maxdepth" "$max_depth" "(")
+    local first=true
+    local indicator
+    for indicator in "${MOLE_PURGE_PROJECT_INDICATORS[@]}"; do
+        if [[ "$first" == "true" ]]; then
+            first=false
+        else
+            find_args+=("-o")
+        fi
+        find_args+=("-name" "$indicator")
+    done
+    find_args+=(")" "-print" "-quit")
+
+    run_with_timeout "$indicator_timeout" find "${find_args[@]}" 2> /dev/null | grep -q .
+}
+
+# Discover candidate project roots without scanning the whole home directory.
+discover_project_cache_roots() {
+    local -a roots=()
+    local root
+
+    for root in "${MOLE_PURGE_DEFAULT_SEARCH_PATHS[@]}"; do
+        [[ -d "$root" ]] && roots+=("$root")
+    done
+
+    while IFS= read -r root; do
+        [[ -d "$root" ]] && roots+=("$root")
+    done < <(mole_purge_read_paths_config "$HOME/.config/mole/purge_paths")
+
+    local dir
+    local base
+    for dir in "$HOME"/*/; do
+        [[ -d "$dir" ]] || continue
+        dir="${dir%/}"
+        base=$(basename "$dir")
+
+        case "$base" in
+            .* | Library | Applications | Movies | Music | Pictures | Public)
+                continue
+                ;;
+        esac
+
+        if project_cache_has_indicators "$dir" 5; then
+            roots+=("$dir")
         fi
     done
-    # Fallback: look for project markers near $HOME.
-    if [[ "$has_dev_projects" == "false" ]]; then
-        local -a project_markers=(
-            "node_modules"
-            ".git"
-            "target"
-            "go.mod"
-            "Cargo.toml"
-            "package.json"
-            "pom.xml"
-            "build.gradle"
-        )
-        local spinner_active=false
-        if [[ -t 1 ]]; then
-            MOLE_SPINNER_PREFIX="  "
-            start_inline_spinner "Detecting dev projects..."
-            spinner_active=true
-        fi
-        for marker in "${project_markers[@]}"; do
-            if run_with_timeout 3 sh -c "find '$HOME' -maxdepth 2 -name '$marker' -not -path '*/Library/*' -not -path '*/.Trash/*' 2>/dev/null | head -1" | grep -q .; then
-                has_dev_projects=true
-                break
-            fi
-        done
-        if [[ "$spinner_active" == "true" ]]; then
-            stop_inline_spinner 2> /dev/null || true
-            # Extra clear to prevent spinner character remnants in terminal
-            [[ -t 1 ]] && printf "\r\033[2K" >&2 || true
-        fi
-        [[ "$has_dev_projects" == "false" ]] && return 0
+
+    [[ ${#roots[@]} -eq 0 ]] && return 0
+
+    printf '%s\n' "${roots[@]}" | LC_ALL=C sort -u
+}
+
+# Scan a project root for supported build caches while pruning heavy subtrees.
+scan_project_cache_root() {
+    local root="$1"
+    local output_file="$2"
+    local scan_timeout="${MOLE_PROJECT_CACHE_SCAN_TIMEOUT:-6}"
+    [[ -d "$root" ]] || return 0
+
+    local -a find_args=(
+        find -P "$root" -maxdepth 9 -mount
+        "(" -name "Library" -o -name ".Trash" -o -name "node_modules" -o -name ".git" -o -name ".svn" -o -name ".hg" -o -name ".venv" -o -name "venv" -o -name ".pnpm-store" -o -name ".fvm" -o -name "DerivedData" -o -name "Pods" ")"
+        -prune -o
+        -type d
+        "(" -name ".next" -o -name "__pycache__" -o -name ".dart_tool" ")"
+        -print
+    )
+
+    local status=0
+    run_with_timeout "$scan_timeout" "${find_args[@]}" >> "$output_file" 2> /dev/null || status=$?
+
+    if [[ $status -eq 124 ]]; then
+        debug_log "Project cache scan timed out: $root"
+    elif [[ $status -ne 0 ]]; then
+        debug_log "Project cache scan failed (${status}): $root"
     fi
+
+    return 0
+}
+
+# Next.js/Python/Flutter project caches scoped to discovered project roots.
+clean_project_caches() {
+    stop_inline_spinner 2> /dev/null || true
+
+    local matches_tmp_file
+    matches_tmp_file=$(create_temp_file)
+
+    local -a scan_roots=()
+    local root
+    while IFS= read -r root; do
+        [[ -n "$root" ]] && scan_roots+=("$root")
+    done < <(discover_project_cache_roots)
+
+    [[ ${#scan_roots[@]} -eq 0 ]] && return 0
+
     if [[ -t 1 ]]; then
         MOLE_SPINNER_PREFIX="  "
         start_inline_spinner "Searching project caches..."
     fi
-    local nextjs_tmp_file
-    nextjs_tmp_file=$(create_temp_file)
-    local pycache_tmp_file
-    pycache_tmp_file=$(create_temp_file)
-    local flutter_tmp_file
-    flutter_tmp_file=$(create_temp_file)
-    local find_timeout=30
-    # Parallel scans (Next.js and __pycache__).
-    # Note: -maxdepth must come before -name for BSD find compatibility
-    (
-        command find -P "$HOME" -maxdepth 3 -mount -type d -name ".next" \
-            -not -path "*/Library/*" \
-            -not -path "*/.Trash/*" \
-            -not -path "*/node_modules/*" \
-            -not -path "*/.*" \
-            2> /dev/null || true
-    ) > "$nextjs_tmp_file" 2>&1 &
-    local next_pid=$!
-    (
-        command find -P "$HOME" -maxdepth 3 -mount -type d -name "__pycache__" \
-            -not -path "*/Library/*" \
-            -not -path "*/.Trash/*" \
-            -not -path "*/node_modules/*" \
-            -not -path "*/.*" \
-            2> /dev/null || true
-    ) > "$pycache_tmp_file" 2>&1 &
-    local py_pid=$!
-    (
-        command find -P "$HOME" -maxdepth 5 -mount -type d -name ".dart_tool" \
-            -not -path "*/Library/*" \
-            -not -path "*/.Trash/*" \
-            -not -path "*/node_modules/*" \
-            -not -path "*/.fvm/*" \
-            2> /dev/null || true
-    ) > "$flutter_tmp_file" 2>&1 &
-    local flutter_pid=$!
-    local elapsed=0
-    local check_interval=0.2 # Check every 200ms instead of 1s for smoother experience
-    while [[ $(echo "$elapsed < $find_timeout" | awk '{print ($1 < $2)}') -eq 1 ]]; do
-        if ! kill -0 $next_pid 2> /dev/null && ! kill -0 $py_pid 2> /dev/null && ! kill -0 $flutter_pid 2> /dev/null; then
-            break
-        fi
-        sleep $check_interval
-        elapsed=$(echo "$elapsed + $check_interval" | awk '{print $1 + $2}')
-    done
-    # Kill stuck scans after timeout.
-    for pid in $next_pid $py_pid $flutter_pid; do
-        if kill -0 "$pid" 2> /dev/null; then
-            kill -TERM "$pid" 2> /dev/null || true
-            local grace_period=0
-            while [[ $grace_period -lt 20 ]]; do
-                if ! kill -0 "$pid" 2> /dev/null; then
-                    break
-                fi
-                sleep 0.1
-                grace_period=$((grace_period + 1))
-            done
-            if kill -0 "$pid" 2> /dev/null; then
-                kill -KILL "$pid" 2> /dev/null || true
-            fi
-            wait "$pid" 2> /dev/null || true
-        else
-            wait "$pid" 2> /dev/null || true
-        fi
+
+    for root in "${scan_roots[@]}"; do
+        scan_project_cache_root "$root" "$matches_tmp_file"
     done
+
     if [[ -t 1 ]]; then
         stop_inline_spinner
     fi
-    while IFS= read -r next_dir; do
-        [[ -d "$next_dir/cache" ]] && safe_clean "$next_dir/cache"/* "Next.js build cache" || true
-    done < "$nextjs_tmp_file"
-    while IFS= read -r pycache; do
-        [[ -d "$pycache" ]] && safe_clean "$pycache"/* "Python bytecode cache" || true
-    done < "$pycache_tmp_file"
-    while IFS= read -r flutter_tool; do
-        if [[ -d "$flutter_tool" ]]; then
-            safe_clean "$flutter_tool" "Flutter build cache (.dart_tool)" || true
-            local build_dir="$(dirname "$flutter_tool")/build"
-            if [[ -d "$build_dir" ]]; then
-                safe_clean "$build_dir" "Flutter build cache (build/)" || true
-            fi
-        fi
-    done < "$flutter_tmp_file"
+
+    while IFS= read -r cache_dir; do
+        case "$(basename "$cache_dir")" in
+            ".next")
+                [[ -d "$cache_dir/cache" ]] && safe_clean "$cache_dir/cache"/* "Next.js build cache" || true
+                ;;
+            "__pycache__")
+                [[ -d "$cache_dir" ]] && safe_clean "$cache_dir"/* "Python bytecode cache" || true
+                ;;
+            ".dart_tool")
+                if [[ -d "$cache_dir" ]]; then
+                    safe_clean "$cache_dir" "Flutter build cache (.dart_tool)" || true
+                    local build_dir="$(dirname "$cache_dir")/build"
+                    if [[ -d "$build_dir" ]]; then
+                        safe_clean "$build_dir" "Flutter build cache (build/)" || true
+                    fi
+                fi
+                ;;
+        esac
+    done < <(LC_ALL=C sort -u "$matches_tmp_file" 2> /dev/null)
 }
diff --git a/lib/core/timeout.sh b/lib/core/timeout.sh
index ae9779a..9f1b2f4 100644
--- a/lib/core/timeout.sh
+++ b/lib/core/timeout.sh
@@ -20,12 +20,18 @@ readonly MOLE_TIMEOUT_LOADED=1
 # Recommendation: Install coreutils for reliable timeout support
 #   brew install coreutils
 #
+# Fallback order:
+#   1. gtimeout / timeout
+#   2. perl helper with dedicated process group cleanup
+#   3. shell-based fallback (last resort)
+#
 # The shell-based fallback has known limitations:
 #   - May not clean up all child processes
 #   - Has race conditions in edge cases
-#   - Less reliable than native timeout command
+#   - Less reliable than native timeout/perl helper
 if [[ -z "${MO_TIMEOUT_INITIALIZED:-}" ]]; then
     MO_TIMEOUT_BIN=""
+    MO_TIMEOUT_PERL_BIN=""
     for candidate in gtimeout timeout; do
         if command -v "$candidate" > /dev/null 2>&1; then
             MO_TIMEOUT_BIN="$candidate"
@@ -36,8 +42,15 @@ if [[ -z "${MO_TIMEOUT_INITIALIZED:-}" ]]; then
         fi
     done
 
+    if [[ -z "$MO_TIMEOUT_BIN" ]] && command -v perl > /dev/null 2>&1; then
+        MO_TIMEOUT_PERL_BIN="$(command -v perl)"
+        if [[ "${MO_DEBUG:-0}" == "1" ]]; then
+            echo "[TIMEOUT] Using perl fallback: $MO_TIMEOUT_PERL_BIN" >&2
+        fi
+    fi
+
     # Log warning if no timeout command available
-    if [[ -z "$MO_TIMEOUT_BIN" ]] && [[ "${MO_DEBUG:-0}" == "1" ]]; then
+    if [[ -z "$MO_TIMEOUT_BIN" && -z "$MO_TIMEOUT_PERL_BIN" ]] && [[ "${MO_DEBUG:-0}" == "1" ]]; then
         echo "[TIMEOUT] No timeout command found, using shell fallback" >&2
         echo "[TIMEOUT] Install coreutils for better reliability: brew install coreutils" >&2
     fi
@@ -95,6 +108,66 @@ run_with_timeout() {
         return $?
     fi
 
+    # Use perl helper when timeout command is unavailable.
+    if [[ -n "${MO_TIMEOUT_PERL_BIN:-}" ]]; then
+        if [[ "${MO_DEBUG:-0}" == "1" ]]; then
+            echo "[TIMEOUT] Perl fallback, ${duration}s: $*" >&2
+        fi
+        "$MO_TIMEOUT_PERL_BIN" -e '
+            use strict;
+            use warnings;
+            use POSIX qw(:sys_wait_h setsid);
+            use Time::HiRes qw(time sleep);
+
+            my $duration = 0 + shift @ARGV;
+            $duration = 1 if $duration <= 0;
+
+            my $pid = fork();
+            defined $pid or exit 125;
+
+            if ($pid == 0) {
+                setsid() or exit 125;
+                exec @ARGV;
+                exit 127;
+            }
+
+            my $deadline = time() + $duration;
+
+            while (1) {
+                my $result = waitpid($pid, WNOHANG);
+                if ($result == $pid) {
+                    if (WIFEXITED($?)) {
+                        exit WEXITSTATUS($?);
+                    }
+                    if (WIFSIGNALED($?)) {
+                        exit 128 + WTERMSIG($?);
+                    }
+                    exit 1;
+                }
+
+                if (time() >= $deadline) {
+                    kill "TERM", -$pid;
+                    sleep 0.5;
+
+                    for (1 .. 6) {
+                        $result = waitpid($pid, WNOHANG);
+                        if ($result == $pid) {
+                            exit 124;
+                        }
+                        sleep 0.25;
+                    }
+
+                    kill "KILL", -$pid;
+                    waitpid($pid, 0);
+                    exit 124;
+                }
+
+                sleep 0.1;
+            }
+        ' "$duration" "$@"
+        return $?
+    fi
+
     # ========================================================================
     # Shell-based fallback implementation
     # ========================================================================
diff --git a/tests/clean_system_caches.bats b/tests/clean_system_caches.bats
index 295113d..a034c96 100644
--- a/tests/clean_system_caches.bats
+++ b/tests/clean_system_caches.bats
@@ -119,11 +119,13 @@ setup() {
 }
 
 @test "clean_project_caches completes without errors" {
-    mkdir -p "$HOME/projects/test-app/.next/cache"
-    mkdir -p "$HOME/projects/python-app/__pycache__"
+    mkdir -p "$HOME/Projects/test-app/.next/cache"
+    mkdir -p "$HOME/Projects/python-app/__pycache__"
 
-    touch "$HOME/projects/test-app/.next/cache/test.cache"
-    touch "$HOME/projects/python-app/__pycache__/module.pyc"
+    touch "$HOME/Projects/test-app/package.json"
+    touch "$HOME/Projects/python-app/pyproject.toml"
+    touch "$HOME/Projects/test-app/.next/cache/test.cache"
+    touch "$HOME/Projects/python-app/__pycache__/module.pyc"
 
     run bash -c "
         export DRY_RUN=true
@@ -133,39 +135,142 @@ setup() {
     "
     [ "$status" -eq 0 ]
 
-    rm -rf "$HOME/projects"
+    rm -rf "$HOME/Projects"
 }
 
-@test "clean_project_caches handles timeout gracefully" {
-    if ! command -v gtimeout >/dev/null 2>&1 && ! command -v timeout >/dev/null 2>&1; then
-        skip "gtimeout/timeout not available"
+@test "clean_project_caches scans configured roots instead of HOME" {
+    mkdir -p "$HOME/.config/mole"
+    mkdir -p "$HOME/CustomProjects/app/.next/cache"
+    touch "$HOME/CustomProjects/app/package.json"
+
+    local fake_bin
+    fake_bin="$(mktemp -d "$HOME/find-bin.XXXXXX")"
+    local find_log="$HOME/find.log"
+
+    cat > "$fake_bin/find" <<EOF
+#!/bin/bash
+printf '%s\n' "\$*" >> "$find_log"
+root=""
+prev=""
+for arg in "\$@"; do
+    if [[ "\$prev" == "-P" ]]; then
+        root="\$arg"
+        break
     fi
+    prev="\$arg"
+done
+if [[ "\$root" == "$HOME/CustomProjects" ]]; then
+    printf '%s\n' "$HOME/CustomProjects/app/.next"
+fi
+EOF
+    chmod +x "$fake_bin/find"
 
-    mkdir -p "$HOME/test-project/.next"
+    run env HOME="$HOME" PROJECT_ROOT="$PROJECT_ROOT" PATH="$fake_bin:$PATH" bash --noprofile --norc <<'EOF'
+set -euo pipefail
+printf '%s\n' "$HOME/CustomProjects" > "$HOME/.config/mole/purge_paths"
+source "$PROJECT_ROOT/lib/core/common.sh"
+source "$PROJECT_ROOT/lib/clean/caches.sh"
+run_with_timeout() { shift; "$@"; }
+safe_clean() { echo "$2|$1"; }
+clean_project_caches
+EOF
+    [ "$status" -eq 0 ]
+    [[ "$output" == *"Next.js build cache"* ]]
+    grep -q -- "-P $HOME/CustomProjects " "$find_log"
+    ! grep -q -- "-P $HOME " "$find_log"
 
-    function find() {
-        sleep 2  # Simulate slow find
-        echo "$HOME/test-project/.next"
-    }
-    export -f find
+    rm -rf "$HOME/CustomProjects" "$HOME/.config/mole" "$fake_bin" "$find_log"
+}
 
-    timeout_cmd="timeout"
-    command -v timeout >/dev/null 2>&1 || timeout_cmd="gtimeout"
+@test "clean_project_caches auto-detects top-level project containers" {
+    mkdir -p "$HOME/go/src/demo/.next/cache"
+    touch "$HOME/go/src/demo/go.mod"
+    touch "$HOME/go/src/demo/.next/cache/test.cache"
 
-    run $timeout_cmd 15 bash -c "
-        source '$PROJECT_ROOT/lib/core/common.sh'
-        source '$PROJECT_ROOT/lib/clean/caches.sh'
-        clean_project_caches
-    "
-    [ "$status" -eq 0 ] || [ "$status" -eq 124 ]
+    run env HOME="$HOME" PROJECT_ROOT="$PROJECT_ROOT" bash --noprofile --norc <<'EOF'
+set -euo pipefail
+source "$PROJECT_ROOT/lib/core/common.sh"
+source "$PROJECT_ROOT/lib/clean/caches.sh"
+safe_clean() { echo "$2|$1"; }
+clean_project_caches
+EOF
+    [ "$status" -eq 0 ]
+    [[ "$output" == *"Next.js build cache|$HOME/go/src/demo/.next/cache/test.cache"* ]]
 
-    rm -rf "$HOME/test-project"
+    rm -rf "$HOME/go"
+}
+
+@test "clean_project_caches auto-detects nested GOPATH-style project containers" {
+    mkdir -p "$HOME/go/src/github.com/example/demo/.next/cache"
+    touch "$HOME/go/src/github.com/example/demo/go.mod"
+    touch "$HOME/go/src/github.com/example/demo/.next/cache/test.cache"
+
+    run env HOME="$HOME" PROJECT_ROOT="$PROJECT_ROOT" bash --noprofile --norc <<'EOF'
+set -euo pipefail
+source "$PROJECT_ROOT/lib/core/common.sh"
+source "$PROJECT_ROOT/lib/clean/caches.sh"
+safe_clean() { echo "$2|$1"; }
+clean_project_caches
+EOF
+    [ "$status" -eq 0 ]
+    [[ "$output" == *"Next.js build cache|$HOME/go/src/github.com/example/demo/.next/cache/test.cache"* ]]
+
+    rm -rf "$HOME/go"
+}
+
+@test "clean_project_caches skips stalled root scans" {
+    mkdir -p "$HOME/.config/mole"
+    mkdir -p "$HOME/SlowProjects/app"
+    printf '%s\n' "$HOME/SlowProjects" > "$HOME/.config/mole/purge_paths"
+
+    local fake_bin
+    fake_bin="$(mktemp -d "$HOME/find-timeout.XXXXXX")"
+
+    cat > "$fake_bin/find" <<EOF
+#!/bin/bash
+root=""
+prev=""
+for arg in "\$@"; do
+    if [[ "\$prev" == "-P" ]]; then
+        root="\$arg"
+        break
+    fi
+    prev="\$arg"
+done
+if [[ "\$root" == "$HOME/SlowProjects" ]]; then
+    trap "" TERM
+    sleep 30
+    exit 0
+fi
+exit 0
+EOF
+    chmod +x "$fake_bin/find"
+
+    run /usr/bin/perl -e 'alarm 8; exec @ARGV' env -i HOME="$HOME" PROJECT_ROOT="$PROJECT_ROOT" PATH="$fake_bin:$PATH:/usr/bin:/bin:/usr/sbin:/sbin" TERM="${TERM:-xterm-256color}" bash --noprofile --norc <<'EOF'
+set -euo pipefail
+source "$PROJECT_ROOT/lib/core/common.sh"
+source "$PROJECT_ROOT/lib/clean/caches.sh"
+MO_TIMEOUT_BIN=""
+export MOLE_PROJECT_CACHE_DISCOVERY_TIMEOUT=0.5
+export MOLE_PROJECT_CACHE_SCAN_TIMEOUT=0.5
+SECONDS=0
+clean_project_caches
+echo "ELAPSED=$SECONDS"
+EOF
+    [ "$status" -eq 0 ]
+    [[ "$output" == *"ELAPSED="* ]]
+    elapsed=$(printf '%s\n' "$output" | awk -F= '/ELAPSED=/{print $2}' | tail -1)
+    [[ "$elapsed" =~ ^[0-9]+$ ]]
+    (( elapsed < 5 ))
+
+    rm -rf "$HOME/.config/mole" "$HOME/SlowProjects" "$fake_bin"
 }
 
 @test "clean_project_caches excludes Library and Trash directories" {
     mkdir -p "$HOME/Library/.next/cache"
     mkdir -p "$HOME/.Trash/.next/cache"
-    mkdir -p "$HOME/projects/.next/cache"
+    mkdir -p "$HOME/Projects/app/.next/cache"
+    touch "$HOME/Projects/app/package.json"
 
     run bash -c "
         export DRY_RUN=true
@@ -175,5 +280,5 @@ setup() {
     "
     [ "$status" -eq 0 ]
 
-    rm -rf "$HOME/projects"
+    rm -rf "$HOME/Projects"
 }
diff --git a/tests/regression.bats b/tests/regression.bats
index b61b7e7..202c0d3 100644
--- a/tests/regression.bats
+++ b/tests/regression.bats
@@ -98,6 +98,36 @@ setup() {
     [[ "$result" == "timeout_works" ]]
 }
 
+@test "run_with_timeout perl fallback stops TERM-ignoring commands" {
+    local fake_dir="$BATS_TEST_TMPDIR/timeout-bin"
+    mkdir -p "$fake_dir"
+    local fake_cmd="$fake_dir/hang.sh"
+
+    cat > "$fake_cmd" <<'EOF'
+#!/bin/bash
+trap "" TERM
+sleep 30
+EOF
+    chmod +x "$fake_cmd"
+
+    run /usr/bin/perl -e 'alarm 8; exec @ARGV' env FAKE_CMD="$fake_cmd" bash --noprofile --norc <<'EOF'
+set -euo pipefail
+source "$PROJECT_ROOT/lib/core/timeout.sh"
+MO_TIMEOUT_BIN=""
+SECONDS=0
+set +e
+run_with_timeout 1 "$FAKE_CMD"
+status=$?
+set -e
+echo "STATUS=$status ELAPSED=$SECONDS"
+EOF
+    [ "$status" -eq 0 ]
+    [[ "$output" == *"STATUS=124"* ]]
+    elapsed=$(printf '%s\n' "$output" | awk '{for (i = 1; i <= NF; i++) if ($i ~ /^ELAPSED=/) {split($i, kv, "="); print kv[2]}}' | tail -1)
+    [[ "$elapsed" =~ ^[0-9]+$ ]]
+    (( elapsed < 6 ))
+}
+
 @test "empty version string is handled gracefully" {
     result=$(bash -c '
         latest=""