vibed improved gc

lib/commands.nix

@@ -1,6 +1,15 @@
 { pkgs }:
 let
   swaymsg = "${pkgs.sway}/bin/swaymsg";
+  systemNotify = pkgs.writeShellApplication {
+    name = "system-notify";
+    runtimeInputs = [
+      pkgs.coreutils
+      pkgs.libnotify
+      pkgs.util-linux
+    ];
+    text = builtins.readFile ../util/system_notify.sh;
+  };
 in
 {
   uwsm = "${pkgs.uwsm}/bin/uwsm-app --";
@@ -9,6 +18,7 @@ in
   lock = "${pkgs.swaylock}/bin/swaylock --daemonize";
   term = "${pkgs.foot}/bin/footclient";
   notify = "${pkgs.libnotify}/bin/notify-send";
+  "system-notify" = "${systemNotify}/bin/system-notify";
   nag = "${pkgs.sway}/bin/swaynag --edge bottom";
   dmenu = "${pkgs.rofi-unwrapped}/bin/rofi";
   espanso = "${pkgs.espanso-wayland}/bin/espanso cmd";

nixos/modules/base.nix

@@ -2,6 +2,15 @@
 let
   autoUpgradeUser = "alisceon";
   flakeRef = "path:${repoLocalPath}";
+  devFlakeGarbageCollect = pkgs.writeShellApplication {
+    name = "dev-flake-garbage-collect";
+    runtimeInputs = [
+      pkgs.coreutils
+      pkgs.findutils
+      pkgs.gnugrep
+    ];
+    text = builtins.readFile ../../util/dev_flake_gc.sh;
+  };
 in
 {
   boot = {
@@ -34,10 +43,35 @@ in
     runGarbageCollection = true;
   };
 
-  systemd.services.nixos-upgrade.preStart = ''
+  systemd = {
+    services = {
+      nixos-upgrade.preStart = ''
         ${pkgs.util-linux}/bin/runuser -u ${autoUpgradeUser} -- ${lib.getExe config.nix.package} flake update --flake ${lib.escapeShellArg flakeRef}
       '';
 
+      dev-flake-garbage-collect = {
+        description = "Remove stale development flake caches and build symlinks";
+        wants = [ "nix-gc.service" ];
+        before = [ "nix-gc.service" ];
+        serviceConfig = {
+          Type = "oneshot";
+          ExecStart = lib.getExe devFlakeGarbageCollect;
+          Nice = 10;
+          IOSchedulingClass = "idle";
+        };
+      };
+    };
+
+    timers.dev-flake-garbage-collect = {
+      wantedBy = [ "timers.target" ];
+      timerConfig = {
+        OnCalendar = "weekly";
+        Persistent = true;
+        RandomizedDelaySec = "3h";
+      };
+    };
+  };
+
   nix = {
     settings = {
       experimental-features = [ "nix-command" "flakes" ];

nixos/modules/profiles/workstation.nix

@@ -1,4 +1,12 @@
-{ pkgs, pkgs-unstable, ... }:
+{ pkgs, pkgs-unstable, lib, ... }:
+let
+  commands = import ../../../lib/commands.nix { inherit pkgs; };
+  systemNotify = commands."system-notify";
+  notify = urgency: title: body:
+    "${systemNotify} ${lib.escapeShellArgs [ urgency title body ]}";
+  notifyFailure = title: service:
+    "${systemNotify} ${lib.escapeShellArgs [ "critical" title ]} \"${service} ended with: $SERVICE_RESULT\"";
+in
 {
   boot = {
     plymouth = {
@@ -53,6 +61,34 @@
     8888
   ];
 
+  systemd.services = {
+    nixos-upgrade = {
+      preStart = lib.mkBefore ''
+        ${notify "normal" "System update started" "Updating flake inputs and preparing the NixOS switch."}
+      '';
+      postStop = ''
+        if [ "$SERVICE_RESULT" = "success" ]; then
+          ${notify "normal" "System update finished" "The automated NixOS update completed successfully."}
+        else
+          ${notifyFailure "System update failed" "nixos-upgrade.service"}
+        fi
+      '';
+    };
+
+    nix-gc = {
+      preStart = ''
+        ${notify "normal" "Garbage collection started" "Cleaning old Nix generations and unreferenced store paths."}
+      '';
+      postStop = ''
+        if [ "$SERVICE_RESULT" = "success" ]; then
+          ${notify "normal" "Garbage collection finished" "Nix store garbage collection completed successfully."}
+        else
+          ${notifyFailure "Garbage collection failed" "nix-gc.service"}
+        fi
+      '';
+    };
+  };
+
   environment = {
     systemPackages = [
       pkgs-unstable.discord

util/dev_flake_gc.sh

@@ -0,0 +1,101 @@
+set -o pipefail
+
+retention_days="30"
+scan_roots=(
+  /
+  /home
+  /root
+  /srv
+  /opt
+  /tmp
+  /var/tmp
+  /var/lib
+)
+
+root_seen() {
+  local candidate="$1"
+  local seen
+
+  for seen in "${seen_roots[@]}"; do
+    [ "$candidate" = "$seen" ] && return 0
+  done
+
+  return 1
+}
+
+has_recent_activity() {
+  local path="$1"
+
+  find "$path" \
+    -xdev \
+    \( -name .git -o -name .hg -o -name .svn -o -name node_modules -o -name target \) -prune \
+    -o -mindepth 1 -mtime "-$retention_days" -print -quit 2>/dev/null \
+    | grep -q .
+}
+
+is_nix_store_symlink() {
+  local link="$1"
+  local target
+
+  target="$(readlink "$link" 2>/dev/null || true)"
+  case "$target" in
+    /nix/store/*) return 0 ;;
+    *) return 1 ;;
+  esac
+}
+
+cleanup_direnv() {
+  local direnv_dir="$1"
+  local project_dir
+
+  project_dir="$(dirname "$direnv_dir")"
+
+  if [ ! -e "$project_dir/flake.nix" ] \
+    && [ ! -e "$direnv_dir/flake-profile" ] \
+    && [ ! -e "$direnv_dir/gcroots" ]; then
+    return
+  fi
+
+  if has_recent_activity "$project_dir"; then
+    return
+  fi
+
+  echo "Removing stale nix-direnv cache: $direnv_dir"
+  rm -rf --one-file-system "$direnv_dir"
+}
+
+cleanup_result_link() {
+  local link="$1"
+
+  if ! is_nix_store_symlink "$link"; then
+    return
+  fi
+
+  echo "Removing stale Nix build result symlink: $link"
+  rm -f "$link"
+}
+
+seen_roots=()
+
+for root in "${scan_roots[@]}"; do
+  [ -d "$root" ] || continue
+  root="$(readlink -f "$root")"
+  root_seen "$root" && continue
+  seen_roots+=("$root")
+
+  find "$root" \
+    -xdev \
+    \( -path /nix -o -path /proc -o -path /sys -o -path /dev -o -path /run -o -path /boot \) -prune \
+    -o -type d -name .direnv -mtime "+$retention_days" -print0 2>/dev/null \
+    | while IFS= read -r -d "" direnv_dir; do
+      cleanup_direnv "$direnv_dir"
+    done
+
+  find "$root" \
+    -xdev \
+    \( -path /nix -o -path /proc -o -path /sys -o -path /dev -o -path /run -o -path /boot \) -prune \
+    -o -type l \( -name result -o -name "result-*" \) -mtime "+$retention_days" -print0 2>/dev/null \
+    | while IFS= read -r -d "" link; do
+      cleanup_result_link "$link"
+    done
+done

util/system_notify.sh

@@ -0,0 +1,23 @@
+set -o pipefail
+
+target_user="${SYSTEM_NOTIFY_USER:-alisceon}"
+urgency="${1:-normal}"
+title="${2:-System task}"
+body="${3:-}"
+
+uid="$(id -u "$target_user" 2>/dev/null || true)"
+[ -n "$uid" ] || exit 0
+
+runtime_dir="/run/user/$uid"
+bus="$runtime_dir/bus"
+[ -S "$bus" ] || exit 0
+
+runuser -u "$target_user" -- env \
+  XDG_RUNTIME_DIR="$runtime_dir" \
+  DBUS_SESSION_BUS_ADDRESS="unix:path=$bus" \
+  notify-send \
+    --app-name="NixOS maintenance" \
+    --urgency="$urgency" \
+    "$title" \
+    "$body" \
+  || exit 0