Notifications Daemon

The Problem

Linux desktop applications send notifications via the org.freedesktop.Notifications D-Bus interface. A shell must replace the default notification daemon (mako, dunst, GNOME's) with its own — displaying, stacking, and dismissing notifications natively in QML.

The Naive Approach

Writing a daemon in Python/Rust that re-emits notifications over a Unix socket, then polling that socket in QML. This introduces a second process, adds latency, and duplicates D-Bus parsing logic.

💡Mental Model

The notification spec defines a single D-Bus method Notify (app_name, replaces_id, app_icon, summary, body, actions, hints, expire_timeout). A daemon registers on the bus, receives calls, and updates a Notifications model. Quickshell's NotificationDaemon service handles D-Bus registration automatically.

The Idea

Use Quickshell's built-in notification service. Register your shell as the notification daemon via D-Bus. Each incoming Notify creates a NotificationObject in the model. Display them with a reusable NotificationPopup component.

Let's Build It

import Quickshell
import Quickshell.Services.Notifications

Item {
  id: root

  NotificationDaemon {
    id: notifDaemon
    onNotificationReceived: (notif) => {
      notif.timeout = notif.timeout > 0 ? notif.timeout : 5000
      notificationModel.append(notif)
    }
  }

  ListModel { id: notificationModel }

  Column {
    anchors { top: parent.top; right: parent.right }
    spacing: 4

    Repeater {
      model: notificationModel
      delegate: NotificationPopup {
        required property var modelData
        notification: modelData
        onDismissed: notificationModel.remove(index)
      }
    }
  }
}

🛠️Let's Build It

NotificationDaemon claims the org.freedesktop.Notifications bus name and dispatches onNotificationReceived for every incoming notification. The NotificationObject has summary, body, appName, appIcon, urgency, timeout, actions, and hints. To dismiss, call notif.close().

Let's Improve It

Add urgency-based styling (critical notifications stay until dismissed), action buttons (e.g., "Reply" on chat apps), and a notification history accessible from a panel button.

Rectangle {
  color: modelData.urgency === NotificationObject.Critical ? "#e25252" : "#3b3b3b"
  radius: 8
  // ... summary, body, actions
}

⚠️Common Mistake

Not handling replaces_id. If an app sends a notification with the same replaces_id, you should update the existing notification instead of appending a duplicate. Check notif.replacesId and find the matching item in your model.

Under the Hood

Quickshell registers a D-Bus object at /org/freedesktop/Notifications implementing the full spec (including GetCapabilities, GetServerInformation, CloseNotification). It manages the replaces_id deduplication, action invocation (sending ActionInvoked signals back to the app), and timeout timers. The daemon only runs while your shell is alive.

Exercises

Beginner: Display notifications as a simple list in the top-right with 5-second auto-dismiss.

Intermediate: Build a notification center accessible from a bell icon — stack notifications, group by app, support "Clear All".

Advanced: Implement notification inline replies: parse hints for x-kde-replyPlaceholderText, show a text input, and send the reply via InvokeAction.

✅What You've Learned

• Notifications are first-class in Quickshell with NotificationDaemon
• D-Bus registration handled automatically; focus on rendering
• Supports actions, urgency levels, and notification history