{
  config,
  pkgs,
  ...
}: let
  swayTgt = "sway-session.target";
  paths = {
    inaccessible = [
      "-/lost+found"
      "/dev/shm"
      "-%h/.ssh"
      "-%h/.gnupg"
      "-%h/Documents"
      # "-%h/Downloads"
      "-%h/Pictures"
      "-%h/Videos"
      "-%h/Sync"
      "-%h/sync"
    ];
  };
in {
  systemd.user.services = {
    kanshi = {
      Unit = {
        Description = "Dynamic output configuration for Wayland compositors";
        # Documentation = "man:kanshi(1)";
        Documentation = "https://sr.ht/~emersion/kanshi";
        BindsTo = config.services.kanshi.systemdTarget;
      };

      Service = {
        Type = "simple";
        # ExecStart = "/usr/sbin/kanshi";
        ExecStart = "${config.services.kanshi.package}/bin/kanshi";
        Restart = "always";
        RestartSec = "5s";
        LockPersonality = true;
        PrivateTmp = "yes";
        DevicePolicy = "closed";
      };

      Install = {WantedBy = [config.services.kanshi.systemdTarget];};
    };

    waybar = {
      Unit = {
        Description = "Highly customizable Wayland bar for Sway and Wlroots based compositors.";
        Documentation = "https://github.com/Alexays/Waybar/wiki/";
        PartOf = swayTgt;
        After = swayTgt;
      };

      Service = {
        ExecStart = "${pkgs.waybar}/bin/waybar";
        ExecReload = "kill -SIGUSR2 $MAINPID";
        Restart = "on-failure";
        RestartSec = "3s";
        LockPersonality = true;
        PrivateTmp = "yes";
        DevicePolicy = "closed";
      };

      Install = {WantedBy = [swayTgt];};
    };

    autotiling = {
      Unit = {
        Description = "Script for sway and i3 to automatically switch the horizontal / vertical window split orientation";
        Documentation = "https://github.com/nwg-piotr/autotiling";
        BindsTo = swayTgt;
      };

      Service = {
        Type = "simple";
        ExecStart = "${pkgs.autotiling}/bin/autotiling";
        Restart = "always";
        RestartSec = "5s";
        LockPersonality = true;
        PrivateTmp = "yes";
        DevicePolicy = "closed";
      };

      Install = {WantedBy = [swayTgt];};
    };

    albert = {
      Unit = {
        Description = "A C++/Qt based desktop agnostic keyboard launcher that helps you to accomplish your workflows in a breeze";
        Documentation = "https://albertlauncher.github.io/";
        BindsTo = swayTgt;
      };

      Service = {
        Type = "simple";
        # after hm stateVersion bump to 23.05, albert doesn't seem to support explicit wayland.
        Environment = "QT_QPA_PLATFORM=xcb";
        ExecStart = "${pkgs.albert}/bin/albert";
        Restart = "always";
        RestartSec = "3s";
        LockPersonality = true;
        PrivateTmp = "yes";
        DevicePolicy = "closed";
      };

      Install = {WantedBy = [swayTgt];};
    };

    avizo = {
      Unit = {
        # Description = "brightness/volume OSD";
        # Documentation = "https://github.com/misterdanb/avizo";
        BindsTo = swayTgt;
      };

      Service = {
        # Type = "simple";
        # ExecStart = "${pkgs.avizo}/bin/avizo-service";
        Restart = "always";
        RestartSec = "5s";
        PrivateTmp = "yes";
        # DevicePolicy = "closed";
        # NoNewPrivileges = true;
        # LockPersonality = true;
        InaccessiblePaths = [
          "-/lost+found"
          "/dev/shm"
          "-%h/.ssh"
          "-%h/.gnupg"
        ];
        # KeyringMode = "private";
        # SystemCallFilter = "~memfd_create @reboot";
        TimeoutStopFailureMode = "abort";
      };

      Install = {WantedBy = [swayTgt];};
    };

    gopls = let
      sock = "/tmp/.gopls-daemon.sock";
    in {
      Unit = {
        Description = "Go language server";
      };

      Service = {
        Type = "simple";
        ExecStartPre = "bash -c 'rm -v -f /tmp/.gopls-daemon.sock || true'";
        ExecStart = "%h/go/bin/gopls -listen='unix;/tmp/.gopls-daemon.sock'";
        ExecStopPost = "bash -c 'rm -v -f /tmp/.gopls-daemon.sock || true'";
        Restart = "on-failure";
        RestartSec = "1m";
        TimeoutStopFailureMode = "abort";
        SystemCallFilter = "~@reboot @obsolete";
        ProtectProc = "invisible";
        ProcSubset = "pid";
        ProtectHome = true;
        RestrictNamespaces = true;
        NoNewPrivileges = "yes";
        ProtectSystem = "strict";
        DevicePolicy = "closed";
        LockPersonality = true;
        MemoryDenyWriteExecute = true;
        #RestrictAddressFamilies="AF_UNIX AF_INET AF_INET6";
        RestrictAddressFamilies = "AF_UNIX";
        RestrictRealtime = true;
        RestrictSUIDSGID = true;
        SystemCallArchitectures = "native";
      };

      # Install = {WantedBy = [swayTgt];};
      Install = {WantedBy = ["default.target"];};
    };

    ff_nn = let
      flavour = "firefox-nightly";
    in {
      Unit = {
        Description = "sh*tbrowser (${flavour})";
        PartOf = swayTgt;
        After = [swayTgt];
      };

      Service = {
        # Type = "simple";
        Environment = [
          "MOZ_ENABLE_WAYLAND=1"
          "MOZ_DBUS_REMOTE=1"
          "MOZ_USE_XINPUT2=1"
          "QT_QPA_PLATFORM=wayland"
          "XDG_SESSION_TYPE=wayland"
          "SDL_VIDEODRIVER=wayland"
          "NO_AT_BRIDGE=1"
        ];
        ExecStart = "-%h/Downloads/${flavour}/firefox-bin -desktop";
        Restart = "on-failure";
        RestartSec = "5s";
        StartLimitBurst = 3;
        StartLimitInterval = "60s";
        TimeoutStopFailureMode = "abort";
        KeyringMode = "private";
        RestrictNamespaces = true;
        DevicePolicy = "closed";
        ProtectSystem = "strict";
        ProtectHome = "tmpfs";
        InaccessiblePaths = paths.inaccessible;
        BindPaths = [
          "-%h/Downloads/${flavour}"
          "-%h/Downloads/toClear"
          "-%h/.mozilla/firefox"
          "-%h/.cache/mozilla/firefox"
          "-%h/.local"
          "-%h/.fonts"
          "-%h/.config"
        ];
        NoNewPrivileges = true;
        ProtectProc = "invisible";
        ProcSubset = "pid";
        PrivateTmp = "yes";
        LockPersonality = true;
        SystemCallFilter = "~@reboot @obsolete";
        SystemCallArchitectures = "native";
      };

      # Install = {WantedBy = [swayTgt];};
    };
    voidff = let
      execPath = "Downloads/lrg/void/firefox";
    in {
      Unit = {
        Description = "voidfox";
        PartOf = swayTgt;
        After = swayTgt;
      };

      Service = {
        # Type = "simple";
        Environment = [
          "MOZ_ENABLE_WAYLAND=1"
          "MOZ_DBUS_REMOTE=1"
          "MOZ_USE_XINPUT2=1"
          "QT_QPA_PLATFORM=wayland"
          "XDG_SESSION_TYPE=wayland"
          "SDL_VIDEODRIVER=wayland"
          "NO_AT_BRIDGE=1"
        ];
        ExecStart = "-%h/${execPath}/firefox-bin -desktop";
        Restart = "on-failure";
        RestartSec = "5s";
        StartLimitBurst = 3;
        StartLimitInterval = "60s";
        TimeoutStopFailureMode = "abort";
        RestrictNamespaces = true;
        DevicePolicy = "closed";
        ProtectSystem = "strict";
        # ProtectHome = true;
        ProtectHome = "tmpfs";
        InaccessiblePaths = paths.inaccessible;
        BindPaths = [
          "-%h/${execPath}"
          "-%h/Downloads/toClear"
          "-%h/.mozilla/firefox"
          "-%h/.cache/mozilla/firefox"
          "-%h/.local"
          "-%h/.fonts"
          "-%h/.config"
        ];
        NoNewPrivileges = true;
        ProtectProc = "invisible";
        ProcSubset = "pid";
        PrivateTmp = "yes";
        LockPersonality = true;
        SystemCallFilter = "~@reboot @obsolete";
        SystemCallArchitectures = "native";
      };

      # Install = {WantedBy = [swayTgt];};
    };

    battery = {
      Unit = {
        Description = "Power Profiles service";
        PartOf = swayTgt;
      };

      Service = {
        Type = "simple";
        ExecStart = "%h/.local/bin/battery.sh";
        Restart = "on-failure";
        RestartSec = "15s";
        TimeoutStopFailureMode = "abort";
        LockPersonality = true;
        PrivateTmp = "yes";
        DevicePolicy = "closed";
      };
    };

    nextcloud = let
      composeF = "%h/.nextcloud/docker-compose.yml";
    in {
      Unit = {
        Description = "Podman container Nextcloud";
        PartOf = swayTgt;
        Wants = "network-online.target";
        After = "network-online.target";
        RequiresMountsFor = "/run/user/1000/containers";
      };

      Service = {
        CPUQuota = "2%";
        Slice = "nextcloud.slice";
        Environment = "PODMAN_SYSTEMD_UNIT=%n";
        Restart = "on-failure";
        RestartSec = 5;
        TimeoutStartSec = 600;
        # TimeoutStopSec=10;
        ExecStartPre = "/usr/bin/podman-compose -f ${composeF} -p nextcloud down";
        ExecStart = "/usr/bin/podman-compose --podman-run-args=\"--replace\" -f ${composeF} -p nextcloud up --remove-orphans";
        ExecStop = "/usr/bin/podman-compose -f ${composeF} -p nextcloud down";
        Type = "simple";
        Delegate = "no";
        ProtectSystem = "strict";
        ProtectProc = "invisible";
        ProcSubset = "pid";
        DevicePolicy = "closed";
        NoNewPrivileges = true;
        LockPersonality = true;
        InaccessiblePaths = [
          "-/lost+found"
          "/dev/shm"
          "-%h/.ssh"
          "-%h/.gnupg"
        ];
        KeyringMode = "private";
        SystemCallFilter = "~memfd_create @reboot";
        TimeoutStopFailureMode = "abort";
      };

      Install = {
        WantedBy = ["default.target"];
      };
    };

    himalaya-watch = {
      Unit = {
        Description = "Himalaya watcher";
        After = "network.target";
      };
      Service = {
        ExecStart = "${pkgs.himalaya}/bin/himalaya watch -a w";
        Restart = "always";
        RestartSec = 300;
        Environment = "RUST_LOG=debug";
        # ReadWritePaths = "/tmp/himalaya-counter-w";
        ProtectHome = "true";
        ProtectSystem = "true";
        DevicePolicy = "closed";
        NoNewPrivileges = true;
        LockPersonality = true;
        InaccessiblePaths = [
          "-/lost+found"
          "/dev/shm"
          "-%h/.ssh"
          "-%h/.gnupg"
        ];
        # KeyringMode = "private";
      };
      Install = {
        WantedBy = ["default.target"];
      };
    };

    himalaya-notify = {
      Unit = {
        Description = "Himalaya new message notifier";
        After = "network.target";
      };
      Service = {
        ExecStart = "${pkgs.himalaya}/bin/himalaya notify";
        Restart = "always";
        RestartSec = 10;
        Environment = "RUST_LOG=debug";
        ProtectHome = "true";
        ProtectSystem = "true";
        DevicePolicy = "closed";
        NoNewPrivileges = true;
        LockPersonality = true;
        InaccessiblePaths = [
          "-/lost+found"
          "/dev/shm"
          "-%h/.ssh"
          "-%h/.gnupg"
        ];
        # KeyringMode = "private";
      };
      Install = {
        WantedBy = ["default.target"];
      };
    };

    trackerMask = {
      Unit = {Description = "";};

      Service = {
        Type = "oneshot";
        ExecStart = "bash -c 'systemctl --user mask tracker-extract-3.service tracker-miner-fs-3.service tracker-miner-rss-3.service tracker-writeback-3.service tracker-xdg-portal-3.service tracker-miner-fs-control-3.service'";
        DevicePolicy = "closed";
        NoNewPrivileges = true;
        LockPersonality = true;
        InaccessiblePaths = [
          "-/lost+found"
          "/dev/shm"
          "-%h/.ssh"
          "-%h/.gnupg"
        ];
        KeyringMode = "private";
      };
    };

    appr120Mask = {
      Unit = {Description = "";};

      Service = {
        Type = "oneshot";
        ExecStart = "bash -c 'systemctl --user mask app-r120@autostart'";
        DevicePolicy = "closed";
        NoNewPrivileges = true;
        LockPersonality = true;
        InaccessiblePaths = [
          "-/lost+found"
          "/dev/shm"
          "-%h/.ssh"
          "-%h/.gnupg"
        ];
        KeyringMode = "private";
      };
    };
  };

  systemd.user.slices = {
    chromium = {
      Unit = {
        Description = "Slice that limits chromium's resources";
        Before = "slices.target";
      };
      Slice = {
        CPUAccounting = "yes";
        CPUQuota = "220%";

        MemoryAccounting = "yes";
        MemoryHigh = "6G";
        MemoryMax = "6.1G";
      };
    };

    nextcloud = {
      Unit = {Description = "Slice that limits nextcloud's resources";};
      Slice = {
        MemoryAccounting = "yes";
        # MemoryHigh works only in "unified" cgroups mode, NOT in "hybrid" mode
        MemoryHigh = "250M";
        # MemoryMax works in "hybrid" cgroups mode, too
        MemoryMax = "300M";

        CPUAccounting = "yes";
        # CPUQuota=15%;
        CPUQuota = "3%";
      };
    };

    podman = {
      # refs:
      #  https://baykara.medium.com/docker-resource-management-via-cgroups-and-systemd-633b093a835c
      #  https://docs.docker.com/engine/reference/commandline/dockerd/#docker-runtime-execution-op>
      Unit = {
        Description = "Slice that limits podman resources";
        Before = "slices.target";
      };

      Slice = {
        MemoryAccounting = "yes";
        MemoryHigh = "10G";
        MemoryMax = "12G";
        MemorySwapMax = "1G";

        # 100% is an equivalent of full utilization on a single core
        # we allow for 85% here - applies to all docker.service-spawn
        # processes cumulatively
        CPUAccounting = "yes";
        # CPUQuota=85%;
        CPUQuota = "50%";
      };
    };
  };

  systemd.user.timers = {
    battery = {
      Unit = {
        Description = "Power Profiles timer";
      };

      Timer = {
        OnActiveSec = "20s";
        OnUnitActiveSec = "5m";
        Unit = "battery.service";
      };
      Install = {
        WantedBy = ["timers.target"];
      };
    };
  };

  systemd.user.targets = {
    sway-session = {
      Unit = {
        Description = "Sway compositor session";
        Documentation = "man:systemd.special(7)";
        BindsTo = "graphical-session.target";
        Wants = "graphical-session-pre.target";
        After = "graphical-session-pre.target";
        Before = "xdg-desktop-autostart.target";
      };
    };
  };
}