make machine-setup.sh and officer-setup.sh actually run on macOS

Both scripts had real macOS branches already — MACOS_SKIP, Xcode CLT, Docker Desktop
detection — but neither had ever run past its own library load on a real Mac, and
verifying that live is what this commit is. This machine is the Mac.

The root cause was the interpreter, not missing OS coverage: macOS's stock /bin/bash is
3.2.57 (Apple stopped shipping newer once bash went GPLv3) and this machine has no newer
one installed. Both scripts used bash 4+/4.3+ syntax with zero version guard, so a real
run died in seconds — declare -A (base.sh, associative array), local -n (packages.sh,
nameref), mapfile (5 sites), ${var,,} (both scripts' own step() — confirmed --only killed
the ENTIRE run), and machine-setup.sh's own pre-flight hard-refused brew outright ("this
script does not implement yet") even once the bash-4 crash was fixed. Each got rewritten
to its bash-3.2-safe equivalent rather than requiring a newer bash and re-executing under
it — nine call sites, a bounded fix, and one less thing that can go wrong before the
script can report what's wrong.

Past that gate, a live probe run (real account/path prompts, killed before Database/
Services could touch this machine's actual state) reproduced a second bug in the first
few seconds: resolve_user_home used getent (Linux/glibc, absent on macOS) with a
hardcoded /home/<user> fallback, so Layout tried `install -d /home/pastilhas` and failed
with "Operation not supported". Fixed with the portable `eval echo ~user` tilde-expansion
idiom, re-ran the same probe, and it correctly created /Users/pastilhas/officerdev/ and
started a real git clone.

Everything else follows the same shape — an unguarded Linux-only tool with a portable or
brew-based macOS equivalent:

  - grep -oP (4 sites: both --list flags, env.sh's tailnet lookup, build.sh's schema
    table count) — BSD grep has no -P at all. Portable ERE+sed where regex was enough;
    jq where the input was already JSON (tailnet lookup) — jq is already an unconditional
    dependency elsewhere in this script, so that's a correctness fix, not just a port.
  - ss (postgres.sh, proxy.sh — is anything listening on this port, and is it bound wide
    enough for NPM's container to reach) — both silently mis-reported on macOS, since the
    "command not found" was swallowed by 2>/dev/null and read as "nothing's listening".
    New shared `listening_addrs()` in officer-setup's base.sh, branching to lsof.
  - getent hosts (proxy.sh's DNS-wait loop) — same silent-failure shape, would have spun
    its full 30-minute timeout regardless of whether the record actually resolved. macOS
    branch uses dscacheutil.
  - stat -c (layout.sh's ownership check) — BSD stat has no -c, confirmed live ("illegal
    option -- c"), and the failure was VISIBLE and made every layout directory report as
    wrong-owner. Portable file_owner() tries -c then falls back to -f %Su.
  - apt-only Postgres client, NodeSource's Debian-only setup script, lazydocker/lazygit's
    installers (one literally named install_update_linux.sh, the other hardcoding
    "_Linux_" into the release asset URL) — each gets a brew branch, formula names
    verified against the live Homebrew catalog rather than assumed.
  - sudo -u "$USERNAME" to become the SAME account the process already is — real on
    Linux, where this whole script runs as root and dropping to the owner needs no
    password; on macOS the process never escalates in the first place, so re-invoking
    sudo for yourself asks for a real password on every call, or fails outright without
    sudo rights. machine-setup's dev.sh had ~10 inline call sites (git, bun, deno, claude,
    opencode, editor detection) rerouted through a new shared run_as_owner(); officer-
    setup's own as_owner() (already the shared entry point there) got the same branch,
    and six direct sudo call sites in build.sh/secrets.sh/services.sh that bypassed it
    were rerouted through it too.

Three things stay Linux-only rather than getting an unverified macOS implementation,
each skipped with a stated reason at the point it would otherwise run: pm2's boot-
persistence hook (needs a launchd plist generated and loaded, not a systemd unit
printed and eval'd — real, separate work), the Tailscale exit-node NIC/sysctl tuning
(no macOS equivalent concept, and advertising a laptop as an exit node is already the
edge case MACOS_SKIP treats it as), and ufw's bridge-to-host firewall rule (pf is a
different rule language entirely, and Docker Desktop's own VM-based networking may not
even have the problem this rule exists to solve — guessing at a firewall rule felt like
the wrong place to be wrong).

Verified: both --list flags print step names instead of a grep usage error. A bounded
officer-setup.sh run (killed before Database) resolved the real macOS home directory,
created the layout with correct ownership, and began a real git clone — cleaned up
after (rm -rf the test directory, the gitignored .setup-progress file, the stray
install-report). machine-setup.sh's pre-flight now reports "Packages: brew" and reaches
the account/path prompts instead of refusing the OS outright. bash -n clean on all 16
files under bash 3.2, the actual interpreter these scripts run under on a Mac.

Not run further live: Database, Secrets, Services and Proxy would mutate this machine's
real state (a live Postgres, a live set of pm2 processes this session runs through) and
were left for a deliberate, supervised run rather than folded into validation.

scripts/setup/machine-setup/lib/base.sh

@@ -165,25 +165,39 @@ ONLY_STEP="${ONLY_STEP:-}"
 # Keyed on the step title, so the sections themselves stay Linux code with no
 # `if macos` branches threaded through them. The reason is printed, because a
 # silent skip and a missing step look identical.
-declare -A MACOS_SKIP=(
-  ["User account"]="accounts are System Settings' business on a Mac, not a script's"
-  ["Disk space"]="ballast and swap tuning are server concerns"
-  ["Locale"]="macOS manages locale itself"
-  ["Timezone"]="macOS manages the timezone itself"
-  ["Swap"]="macOS sizes its own swap dynamically"
-  ["Emergency disk ballast"]="a server trick for a machine nobody is sitting at"
-  ["earlyoom"]="Linux OOM killer tuning; macOS has its own memory pressure handling"
-  ["inotify watch limit"]="Linux inotify; macOS watches files through FSEvents"
-  ["Sleep and suspend"]="a laptop SHOULD sleep — this stops a server from doing it"
-  ["Boot hang"]="a systemd boot ordering fix"
-  ["SSH access"]="hardening a door a dev machine should not be opening"
-  ["DNS"]="systemd-resolved"
-  ["Network address"]="netplan, and a laptop moves between networks by design"
-  ["fail2ban"]="brute-force protection for an exposed SSH port"
-  ["Unattended upgrades"]="apt; macOS updates through Software Update"
-  ["Firewall"]="ufw; macOS has its own application firewall"
-  ["Shell"]="zsh is already the default, and tmux is a choice you make yourself"
-)
+#
+# A `case` rather than an associative array — `declare -A` is bash 4+, and macOS's own
+# stock `/bin/bash` is 3.2 (Apple hasn't shipped a newer one since bash went GPLv3), with
+# nothing newer installed on a fresh machine. An array keyed on the step title would parse-
+# fail the instant this file is sourced, before a single step could run — which is exactly
+# what happened here until it was measured. Prints the reason on stdout, so the caller reads
+# it with `$(...)`; exit status says whether the title matched anything at all.
+macos_skip_reason() {
+  case "$1" in
+    "User account") echo "accounts are System Settings' business on a Mac, not a script's" ;;
+    "Disk space") echo "ballast and swap tuning are server concerns" ;;
+    "Locale") echo "macOS manages locale itself" ;;
+    "Timezone") echo "macOS manages the timezone itself" ;;
+    "Swap") echo "macOS sizes its own swap dynamically" ;;
+    "Emergency disk ballast") echo "a server trick for a machine nobody is sitting at" ;;
+    "earlyoom") echo "Linux OOM killer tuning; macOS has its own memory pressure handling" ;;
+    "inotify watch limit") echo "Linux inotify; macOS watches files through FSEvents" ;;
+    "Sleep and suspend") echo "a laptop SHOULD sleep — this stops a server from doing it" ;;
+    "Boot hang") echo "a systemd boot ordering fix" ;;
+    "SSH access") echo "hardening a door a dev machine should not be opening" ;;
+    "DNS") echo "systemd-resolved" ;;
+    "Network address") echo "netplan, and a laptop moves between networks by design" ;;
+    "fail2ban") echo "brute-force protection for an exposed SSH port" ;;
+    "Unattended upgrades") echo "apt; macOS updates through Software Update" ;;
+    "Firewall") echo "ufw; macOS has its own application firewall" ;;
+    "Shell") echo "zsh is already the default, and tmux is a choice you make yourself" ;;
+    *) return 1 ;;
+  esac
+}
+
+# `${var,,}` (case-insensitive compare below) is bash 4+ too — this is the portable
+# pre-4 substitute, not a style choice.
+lower() { tr '[:upper:]' '[:lower:]' <<<"$1"; }
 
 step() {
   CURRENT_STEP="$1"
@@ -191,16 +205,19 @@ step() {
   # which one it is. Twenty-six sections, one place.
   declare -F report_section >/dev/null && report_section "$1"
 
-  if [[ "${OS:-}" == "macos" && -n "${MACOS_SKIP[$1]:-}" ]]; then
-    echo ""
-    echo -e "${BOLD}── $1 ──${NC}"
-    echo -e "   ${GREEN}SKIP${NC}: not on macOS — ${MACOS_SKIP[$1]}"
-    SKIP_STEP=true
-    return
+  if [[ "${OS:-}" == "macos" ]]; then
+    local _skip_reason
+    if _skip_reason="$(macos_skip_reason "$1")"; then
+      echo ""
+      echo -e "${BOLD}── $1 ──${NC}"
+      echo -e "   ${GREEN}SKIP${NC}: not on macOS — ${_skip_reason}"
+      SKIP_STEP=true
+      return
+    fi
   fi
 
   if [[ -n "$ONLY_STEP" ]]; then
-    if [[ "${1,,}" == "${ONLY_STEP,,}" ]]; then
+    if [[ "$(lower "$1")" == "$(lower "$ONLY_STEP")" ]]; then
       SKIP_STEP=false
       echo ""
       echo -e "${BOLD}── $1 ──${NC}"
@@ -508,6 +525,24 @@ ask_officer_root() {
 # both of which abort the step.
 user_group() { id -gn "${1:-$USERNAME}" 2>/dev/null || echo "${1:-$USERNAME}"; }
 
+# Run a command as the created account, e.g. `run_as_owner git clone ...`.
+#
+# On Linux this whole script runs as root — refused otherwise, see the pre-flight check
+# above — so `sudo -u "$USERNAME"` from root needs no password; sudo lets root become
+# anyone freely. On macOS the script deliberately never escalates (Homebrew refuses to run
+# as root), so the process already IS "$USERNAME", and re-invoking sudo for the SAME
+# account asks for a real password — potentially many times in one run, dev.sh calls this
+# shape roughly ten times — or fails outright on an account with no sudo rights at all.
+# `dev.sh`'s git/bun/deno/claude/opencode/editor helpers all route through this rather than
+# hand-rolling `sudo -H -u "$USERNAME" ...` each time, so macOS behaviour lives in one place.
+run_as_owner() {
+  if [[ "${OS:-}" == "macos" ]]; then
+    "$@"
+  else
+    sudo -H -u "$USERNAME" "$@"
+  fi
+}
+
 # Run a block as the created user (login shell, inherits HOME)
 as_user() {
   sudo -u "$USERNAME" -i bash -c "$1"

scripts/setup/machine-setup/lib/dev.sh

@@ -47,8 +47,8 @@ MACHINE_SETUP_DEV_LOADED=1
 # has never been configured — the fresh machine this script exists for — reading
 # the current value aborted the run before the section had printed anything.
 # Missing a value is an answer here, not a failure.
-git_get() { (cd / && sudo -H -u "$USERNAME" git config --global --get "$1" 2>/dev/null) || true; }
-git_set() { (cd / && sudo -H -u "$USERNAME" git config --global "$1" "$2"); }
+git_get() { (cd / && run_as_owner git config --global --get "$1" 2>/dev/null) || true; }
+git_set() { (cd / && run_as_owner git config --global "$1" "$2"); }
 
 # Is there anything configured at all?
 git_has_identity() { [[ -n "$(git_get user.name)" || -n "$(git_get user.email)" ]]; }
@@ -102,7 +102,7 @@ install_oh_my_zsh() {
   # failed died here, silently, because the output is redirected: the run just
   # stopped after apt finished installing zsh, with nothing said. Observed on a
   # fresh Hetzner VPS, 2026-08-14.
-  sudo -H -u "$USERNAME" sh -c \
+  run_as_owner sh -c \
     "$(curl -fsSL https://raw.githubusercontent.com/ohmyzsh/ohmyzsh/master/tools/install.sh)" "" --unattended >/dev/null 2>&1 ||
     true
   # Belt and braces: `|| true` above already makes the last command succeed, and
@@ -187,11 +187,11 @@ nvim_clone_config() {
   local repo="$1" dest="${USER_HOME}/.config/nvim"
 
   install -d -m 0755 -o "$USERNAME" -g "$(user_group)" "${USER_HOME}/.config"
-  (cd / && sudo -H -u "$USERNAME" git clone --depth 1 "$repo" "$dest" >/dev/null 2>&1) || return 1
+  (cd / && run_as_owner git clone --depth 1 "$repo" "$dest" >/dev/null 2>&1) || return 1
 
   # The starter is a template, not something to track. Left in place for a
   # config of the user's own, which they will want to keep pulling.
-  [[ "$repo" == *LazyVim/starter* ]] && sudo -u "$USERNAME" rm -rf "${dest}/.git"
+  [[ "$repo" == *LazyVim/starter* ]] && run_as_owner rm -rf "${dest}/.git"
   return 0
 }
 
@@ -230,6 +230,18 @@ node_installed_major() { node -v 2>/dev/null | sed 's/^v//; s/\..*//'; }
 
 install_node() {
   local major="$1"
+
+  # NodeSource's setup script adds an apt repository — it is Debian/Ubuntu-only by name
+  # and by mechanism (checks for dpkg internally), so there is nothing to point it at on
+  # macOS. Homebrew's `node`/`nodejs` formula (both names resolve, confirmed) tracks only
+  # the current release rather than an arbitrary major the way NodeSource's per-major
+  # scripts do — same tradeoff this codebase already accepts for Docker and Xcode CLT on
+  # macOS: brew's own version, not a pinned one.
+  if [[ "${OS:-}" == "macos" ]]; then
+    pkg_install_now nodejs
+    return
+  fi
+
   # NodeSource publishes one setup script per major. Checked before it is piped
   # into a shell, because a 404 page piped to bash is a confusing way to fail.
   curl -fsS -o /dev/null "https://deb.nodesource.com/setup_${major}.x" || {
@@ -358,7 +370,7 @@ ensure_bun_symlink() {
 install_bun() {
   local tag="${1:-}"
   [[ -n "$tag" ]] || return 1
-  (cd / && sudo -H -u "$USERNAME" bash -c "curl -fsSL https://bun.sh/install | bash -s '${tag}'") >/dev/null 2>&1
+  (cd / && run_as_owner bash -c "curl -fsSL https://bun.sh/install | bash -s '${tag}'") >/dev/null 2>&1
   [[ -x "${USER_HOME}/.bun/bin/bun" ]]
 }
 
@@ -367,7 +379,7 @@ install_pm2() { npm install -g pm2 >/dev/null 2>&1; }
 
 deno_installed() { command -v deno &>/dev/null || [[ -x "${USER_HOME}/.deno/bin/deno" ]]; }
 install_deno() {
-  (cd / && sudo -H -u "$USERNAME" bash -c 'curl -fsSL https://deno.land/install.sh | sh') >/dev/null 2>&1
+  (cd / && run_as_owner bash -c 'curl -fsSL https://deno.land/install.sh | sh') >/dev/null 2>&1
   [[ -x "${USER_HOME}/.deno/bin/deno" ]]
 }
 
@@ -434,16 +446,16 @@ agent_is_npm_install() { [[ "$(readlink -f "$(agent_path "$1")" 2>/dev/null)" ==
 agent_version() {
   local bin
   bin="$(agent_path "$1")"
-  [[ -n "$bin" ]] && (cd / && sudo -H -u "$USERNAME" "$bin" --version 2>/dev/null | head -1)
+  [[ -n "$bin" ]] && (cd / && run_as_owner "$bin" --version 2>/dev/null | head -1)
 }
 
 install_claude_code() {
-  (cd / && sudo -H -u "$USERNAME" bash -c "set -e; curl -fsSL ${CLAUDE_INSTALL_URL} | bash") >/dev/null 2>&1
+  (cd / && run_as_owner bash -c "set -e; curl -fsSL ${CLAUDE_INSTALL_URL} | bash") >/dev/null 2>&1
   [[ -x "$(agent_bin claude)" ]]
 }
 
 install_opencode() {
-  (cd / && sudo -H -u "$USERNAME" bash -c "set -e; curl -fsSL ${OPENCODE_INSTALL_URL} | bash") >/dev/null 2>&1
+  (cd / && run_as_owner bash -c "set -e; curl -fsSL ${OPENCODE_INSTALL_URL} | bash") >/dev/null 2>&1
   [[ -x "$(agent_bin opencode)" ]]
 }
 
@@ -471,7 +483,7 @@ editor_candidates() {
 
 # `|| true` for the same reason git_get has it: "not set" is an answer, and an
 # assignment from a function that exits non-zero aborts the run under `set -e`.
-current_editor() { (cd / && sudo -H -u "$USERNAME" bash -lc 'echo "${EDITOR:-}"' 2>/dev/null) || true; }
+current_editor() { (cd / && run_as_owner bash -lc 'echo "${EDITOR:-}"' 2>/dev/null) || true; }
 
 set_system_editor() {
   local editor="$1" path

scripts/setup/machine-setup/lib/packages.sh

@@ -253,13 +253,20 @@ pkg_install() {
 # passed by value cannot be told apart from an empty one once it has been through
 # word splitting.
 #
+# Copies by name via eval rather than `local -n` — namerefs are bash 4.3+, and macOS's
+# stock bash is 3.2. This is the idiom namerefs replaced: build the local array by
+# expanding the CALLER's array name inside a double-quoted eval, which bash 3.2 has always
+# supported. `$2`/`$3` are trusted call-site literals (`present`, `missing`), never
+# user input, so the eval is not taking anything untrusted.
+#
 # Returns non-zero when there is nothing to do, or when the answer was no — in
 # both cases the caller should skip its action. LAST_INSTALLED is cleared on a
 # refusal so the summary does not claim work that never happened.
 announce_plan() {
   local label="$1"
-  local -n _present="$2"
-  local -n _missing="$3"
+  local -a _present _missing
+  eval "_present=(\"\${$2[@]}\")"
+  eval "_missing=(\"\${$3[@]}\")"
 
   echo ""
   info "${label} — installs what is missing, keeps what you already have"

scripts/setup/machine-setup/lib/tailscale.sh

@@ -245,7 +245,18 @@ tailscale_needs_logout() {
 # Routing has to be on before this machine can forward anyone else's packets,
 # whether as an exit node or as a subnet router. Written as a drop-in so it is
 # visible as this script's doing.
+# Both this and install_exit_node_tuning below are Linux-only — sysctl.d, systemd's
+# networkd-dispatcher, ethtool NIC offload flags, none of which macOS has an equivalent
+# concept for. Tailscale itself DOES support acting as an exit node from macOS (that's the
+# `--advertise-exit-node` flag on `tailscale up`, untouched by this guard) — what's
+# unavailable is specifically this forwarding-throughput tuning, which is also a much
+# narrower loss on a Mac: the file's own MACOS_SKIP already treats a laptop advertising as
+# an exit node as an edge case, not the common path a homelab box is.
 enable_ip_forwarding() {
+  if [[ "${OS:-}" == "macos" ]]; then
+    warn "IP-forwarding tuning is Linux-only (sysctl.d) — skipping; the exit node still works, just untuned"
+    return 0
+  fi
   cat >"$TS_EXIT_SYSCTL" <<'EOF'
 # Written by machine-setup: required to forward traffic for other tailnet nodes,
 # as an exit node or as a subnet router.
@@ -265,6 +276,10 @@ EOF
 # once, because the settings are per-interface and do not survive the link going
 # down and back up.
 install_exit_node_tuning() {
+  if [[ "${OS:-}" == "macos" ]]; then
+    warn "NIC offload tuning is Linux-only (networkd-dispatcher, ethtool) — skipping"
+    return 0
+  fi
   pkg_is_installed networkd-dispatcher || pkg_install_now networkd-dispatcher
 
   mkdir -p "$(dirname "$TS_DISPATCHER")"

scripts/setup/machine-setup/lib/tools.sh

@@ -48,7 +48,15 @@ tool_is_installed() { command -v "$(tool_command "$1")" &>/dev/null; }
 # The installers
 # -----------------------------------------------------------------------------
 
+# The installer script this used is literally named install_update_linux.sh — there is no
+# upstream equivalent for macOS to swap in, so this is brew there instead of a raw fetch.
+# All three tools are real Homebrew formulas (confirmed against the live catalogue), which
+# also means macOS gets `brew upgrade` maintenance the raw-fetch path never had.
 tool_install_lazydocker() {
+  if [[ "${OS:-}" == "macos" ]]; then
+    brew install lazydocker
+    return
+  fi
   curl -fsSL https://raw.githubusercontent.com/jesseduffield/lazydocker/master/scripts/install_update_linux.sh |
     DIR=/usr/local/bin bash
 }
@@ -57,7 +65,16 @@ tool_install_lazydocker() {
 # x86_64, so an arm machine downloaded a 404 and tar failed halfway through the
 # run. lazygit spells the architectures x86_64 and arm64, which is neither of the
 # two spellings ARCH uses, hence the mapping.
+#
+# The URL was also hardcoded to `_Linux_` — brew handles macOS instead of this needing a
+# second literal-string branch, see tool_install_lazydocker above for why brew and not a
+# Darwin asset name here.
 tool_install_lazygit() {
+  if [[ "${OS:-}" == "macos" ]]; then
+    brew install lazygit
+    return
+  fi
+
   local version asset url
   case "$ARCH" in
     amd64) asset="x86_64" ;;
@@ -82,7 +99,14 @@ tool_install_lazygit() {
 # Quiet on purpose. The installer ends by printing how to add starship to bash,
 # zsh, ion, tcsh and xonsh — five shells' worth of instructions for a step that
 # already writes the zsh config itself. Errors still come through.
+#
+# starship's own installer IS cross-platform (unlike the two above), but brew on macOS
+# keeps it consistent with the other two tools and gets it `brew upgrade` maintenance.
 tool_install_starship() {
+  if [[ "${OS:-}" == "macos" ]]; then
+    brew install starship
+    return
+  fi
   curl -fsSL https://starship.rs/install.sh | sh -s -- -y -b /usr/local/bin >/dev/null
 }
 

scripts/setup/machine-setup/machine-setup.sh

@@ -46,7 +46,9 @@ while [[ $# -gt 0 ]]; do
       shift
       ;;
     -l | --list)
-      grep -oP '^step "\K[^"]+' "${BASH_SOURCE[0]}"
+      # Portable ERE + sed rather than GNU grep's -P/\K — BSD grep on macOS has no -P at
+      # all and errors immediately ("invalid option -- P"), confirmed live.
+      grep -E '^step "' "${BASH_SOURCE[0]}" | sed -E 's/^step "([^"]+)".*/\1/'
       exit 0
       ;;
     -h | --help)
@@ -114,15 +116,17 @@ info "Machine:  ${OS_NAME} (${ARCH})"
 info "Packages: ${PM:-none detected}"
 [[ "$IS_WSL" == true ]] && warn "WSL detected — the suspend, logind and boot-hang steps do not apply here"
 
-# Everything below this line is written against apt and systemd. Detection above
-# recognises pacman, dnf and brew so the branches have somewhere to hang, but
-# nothing implements them yet — and running the apt path on Arch would half-build
-# a machine and stop somewhere unhelpful. Refuse clearly instead, and relax this
-# list one entry at a time as each package manager grows a real path.
+# Everything below this line is written against apt and systemd, with real macOS/brew
+# branches threaded through where a Mac needs different behaviour (MACOS_SKIP for whole
+# steps that are server-only, `$OS == macos` for the rest). Detection above also recognises
+# pacman and dnf so THEIR branches have somewhere to hang, but nothing implements those yet
+# — running the apt path on Arch would half-build a machine and stop somewhere unhelpful.
+# Refuse clearly instead, and relax this list one entry at a time as each package manager
+# grows a real path.
 case "$PM" in
-  apt) ;;
+  apt | brew) ;;
   "") fail "Could not find a package manager for '${OS_NAME}'." ;;
-  *) fail "${OS_NAME} uses ${PM}, which this script does not implement yet — apt-based systems only, so far." ;;
+  *) fail "${OS_NAME} uses ${PM}, which this script does not implement yet — apt and brew only, so far." ;;
 esac
 
 ask_machine_role
@@ -404,7 +408,9 @@ fi
 
 step "System update"
 if ! skip; then
-  mapfile -t UPGRADABLE < <(pkg_upgradable)
+  # `mapfile` is bash 4+; macOS's stock bash is 3.2. This is the portable substitute.
+  UPGRADABLE=()
+  while IFS= read -r _line; do UPGRADABLE+=("$_line"); done < <(pkg_upgradable)
 
   echo ""
   info "System update — upgrades installed packages to their latest versions"
@@ -2479,7 +2485,9 @@ EOF
   echo "     which is why git's own core.editor is deliberately not set: git"
   echo "     falls back to \$EDITOR, so setting it here covers everything."
   echo ""
-  mapfile -t EDITORS < <(editor_candidates)
+  # mapfile is bash 4+; macOS's stock bash is 3.2.
+  EDITORS=()
+  while IFS= read -r _line; do EDITORS+=("$_line"); done < <(editor_candidates)
   if ((${#EDITORS[@]} == 0)); then
     warn "no editor found to offer — skipping"
   else