add additional daemons

16 files changed, 661 insertions, 21 deletions

diff --git a/Sources/bar/bar.docc/daemons.md b/Sources/bar/bar.docc/daemons.md
index e99ecfc..c73377b 100644
--- a/Sources/bar/bar.docc/daemons.md
+++ b/Sources/bar/bar.docc/daemons.md
@@ -21,7 +21,7 @@ notify_post("bar.touch.<block-name>");
 The ``Notifier`` system in *bar* receives the notification and re-runs the corresponding block's command.
 The block itself stays stateless, it just reads and prints the current state whenever it is called.
 
-For example, the <doc:daemon-bar-volumed> daemon listens for CoreAudio volume change events and posts `bar.touch.volume`.
+For example, the <doc:daemon-volumed> daemon listens for CoreAudio volume change events and posts `bar.touch.volume`.
 The volume block in ``Config`` runs once per notification, prints the current volume, and the bar updates.
 
 ## How to install
@@ -56,27 +56,26 @@ The process is very similar to the one described in the <doc:run-at-login> artic
 ### Audio
 
 - <doc:daemon-volumed>
-<!-- - <doc:daemon-bar-micd> -->
-
-<!-- ### Display -->
-<!---->
-<!-- - <doc:daemon-bar-brightnessd> -->
-<!-- - <doc:daemon-bar-spaced> -->
-<!---->
-<!-- ### Power -->
-<!---->
-<!-- - <doc:daemon-bar-batteryd> -->
-<!---->
-<!-- ### Network -->
-<!---->
-<!-- - <doc:daemon-bar-networkd> -->
+
+### Display
+
+- <doc:daemon-brightnessd>
+- <doc:daemon-spaced>
+
+### Power
+
+- <doc:daemon-batteryd>
+
+### Network
+
+- <doc:daemon-networkd>
 
 ### Media
 
+- <doc:daemon-nowplayingd>
 - <doc:daemon-mpd>
-<!-- - <doc:daemon-bar-nowplayingd> -->
 
-<!-- ### System -->
-<!---->
-<!-- - <doc:daemon-bar-focusd> -->
-<!-- - <doc:daemon-bar-devicesd> -->
+### System
+
+- <doc:daemon-devicesd>
+- <doc:daemon-focusd>
diff --git a/Sources/bar/bar.docc/daemons/daemon-batteryd.md b/Sources/bar/bar.docc/daemons/daemon-batteryd.md
new file mode 100644
index 0000000..db7a5dc
--- /dev/null
+++ b/Sources/bar/bar.docc/daemons/daemon-batteryd.md
@@ -0,0 +1,27 @@
+# batteryd
+
+React to battery and power source changes.
+
+This daemon listens for power source changes via **IOKit** (`IOPowerSources`) and posts a Darwin notification that tells *bar* to refresh the desired block.
+It fires when the battery level changes, the charger is plugged or unplugged, or the machine enters low-power mode.
+
+## How it works
+
+The daemon uses `IOPSNotificationCreateRunLoopSource` to register a callback that fires every time the power source state changes.
+When the callback fires, the daemon calls `notify_post("bar.touch.<block-name>")`.
+
+The ``Notifier`` system in *bar* picks this up and re-runs the block's command.
+
+### Dependencies
+
+- IOKit.framework, CoreFoundation.framework
+
+## Compile
+
+```shell
+cc -o bar-batteryd daemons/batteryd.c -framework IOKit -framework CoreFoundation
+```
+
+## Author
+
+Tommaso Negri [@tommasongr](https://github.com/tommasongr)
diff --git a/Sources/bar/bar.docc/daemons/daemon-brightnessd.md b/Sources/bar/bar.docc/daemons/daemon-brightnessd.md
new file mode 100644
index 0000000..b617e3b
--- /dev/null
+++ b/Sources/bar/bar.docc/daemons/daemon-brightnessd.md
@@ -0,0 +1,27 @@
+# brightnessd
+
+React to display brightness changes.
+
+This daemon listens for display brightness changes via **IOKit** and posts a Darwin notification that tells *bar* to refresh the desired block.
+It fires when the brightness level changes through keyboard keys, the Touch Bar, or System Settings.
+
+## How it works
+
+The daemon uses IOKit notifications to watch for changes to the display backlight service (`AppleBacklightDisplay` or `AppleIntelPanel`).
+When the brightness changes, the daemon calls `notify_post("bar.touch.<block-name>")`.
+
+The ``Notifier`` system in *bar* picks this up and re-runs the block's command.
+
+### Dependencies
+
+- IOKit.framework, CoreFoundation.framework
+
+## Compile
+
+```shell
+cc -o bar-brightnessd daemons/brightnessd.c -framework IOKit -framework CoreFoundation
+```
+
+## Author
+
+Tommaso Negri [@tommasongr](https://github.com/tommasongr)
diff --git a/Sources/bar/bar.docc/daemons/daemon-devicesd.md b/Sources/bar/bar.docc/daemons/daemon-devicesd.md
new file mode 100644
index 0000000..554371d
--- /dev/null
+++ b/Sources/bar/bar.docc/daemons/daemon-devicesd.md
@@ -0,0 +1,30 @@
+# devicesd
+
+React to USB device hotplug events.
+
+This daemon listens for USB device connect and disconnect events via **IOKit** and posts a Darwin notification that tells *bar* to refresh the desired block.
+It fires when you plug in or unplug any USB device, including Bluetooth controllers.
+
+## How it works
+
+The daemon uses IOKit matching notifications to watch for:
+- `IOUSBDevice` — USB device connect and disconnect events.
+- `IOBluetoothHCIController` — Bluetooth controller events.
+
+When a device is added or removed, the daemon calls `notify_post("bar.touch.<block-name>")`.
+
+The ``Notifier`` system in *bar* picks this up and re-runs the block's command.
+
+### Dependencies
+
+- IOKit.framework, CoreFoundation.framework
+
+## Compile
+
+```shell
+cc -o bar-devicesd daemons/devicesd.c -framework IOKit -framework CoreFoundation
+```
+
+## Author
+
+Tommaso Negri [@tommasongr](https://github.com/tommasongr)
diff --git a/Sources/bar/bar.docc/daemons/daemon-focusd.md b/Sources/bar/bar.docc/daemons/daemon-focusd.md
new file mode 100644
index 0000000..73dc5f6
--- /dev/null
+++ b/Sources/bar/bar.docc/daemons/daemon-focusd.md
@@ -0,0 +1,27 @@
+# focusd
+
+React to Focus and Do Not Disturb mode changes.
+
+This daemon listens for Focus mode and DND changes via `DistributedNotificationCenter` and posts a Darwin notification that tells *bar* to refresh the desired block.
+
+## How it works
+
+The daemon registers a distributed notification observer for `com.apple.notificationcenter.dndprefs_changed`, which macOS fires whenever the Focus mode or Do Not Disturb state changes.
+
+When the notification fires, the daemon calls `notify_post("bar.touch.<block-name>")`.
+
+The ``Notifier`` system in *bar* picks this up and re-runs the block's command.
+
+### Dependencies
+
+- CoreFoundation.framework
+
+### Compile
+
+```shell
+cc -o bar-focusd daemons/focusd.c -framework CoreFoundation
+```
+
+## Author
+
+Tommaso Negri [@tommasongr](https://github.com/tommasongr)
diff --git a/Sources/bar/bar.docc/daemons/daemon-networkd.md b/Sources/bar/bar.docc/daemons/daemon-networkd.md
new file mode 100644
index 0000000..cb9c765
--- /dev/null
+++ b/Sources/bar/bar.docc/daemons/daemon-networkd.md
@@ -0,0 +1,31 @@
+# networkd
+
+React to network state changes.
+
+This daemon listens for network configuration changes via **SystemConfiguration** and posts a Darwin notification that tells *bar* to refresh the desired block.
+It fires when the WiFi connects or disconnects, the IP address changes, or a VPN toggles.
+
+## How it works
+
+The daemon uses `SCDynamicStore` to watch for changes to:
+- `State:/Network/Global/IPv4` — IPv4 address changes.
+- `State:/Network/Global/IPv6` — IPv6 address changes.
+- `State:/Network/Interface/en0/AirPort` — WiFi state changes.
+
+When any of these keys change, the daemon calls `notify_post("bar.touch.<block-name>")`.
+
+The ``Notifier`` system in *bar* picks this up and re-runs the block's command.
+
+### Dependencies
+
+- SystemConfiguration.framework, CoreFoundation.framework
+
+## Compile
+
+```shell
+cc -o bar-networkd daemons/networkd.c -framework SystemConfiguration -framework CoreFoundation
+```
+
+## Author
+
+Tommaso Negri [@tommasongr](https://github.com/tommasongr)
diff --git a/Sources/bar/bar.docc/daemons/daemon-nowplayingd.md b/Sources/bar/bar.docc/daemons/daemon-nowplayingd.md
new file mode 100644
index 0000000..9d33929
--- /dev/null
+++ b/Sources/bar/bar.docc/daemons/daemon-nowplayingd.md
@@ -0,0 +1,29 @@
+# nowplayingd
+
+React to music track changes.
+
+This daemon listens for track change notifications from **Music** and **Spotify** via `DistributedNotificationCenter` and posts a Darwin notification that tells *bar* to refresh the desired block.
+
+## How it works
+
+The daemon registers distributed notification observers for:
+- `com.apple.Music.playerInfo` — fired by Music.app when the track changes.
+- `com.spotify.client.PlaybackStateChanged` — fired by Spotify when the track changes.
+
+When either notification fires, the daemon calls `notify_post("bar.touch.<block-name>")`.
+
+The ``Notifier`` system in *bar* picks this up and re-runs the block's command, which can read the current track from any source.
+
+### Dependencies
+
+- CoreFoundation.framework
+
+### Compile
+
+```shell
+cc -o bar-nowplayingd daemons/nowplayingd.c -framework CoreFoundation
+```
+
+## Author
+
+Tommaso Negri [@tommasongr](https://github.com/tommasongr)
diff --git a/Sources/bar/bar.docc/daemons/daemon-spaced.md b/Sources/bar/bar.docc/daemons/daemon-spaced.md
new file mode 100644
index 0000000..1b4cea0
--- /dev/null
+++ b/Sources/bar/bar.docc/daemons/daemon-spaced.md
@@ -0,0 +1,29 @@
+# spaced
+
+React to desktop space changes.
+
+This daemon monitors the active desktop space and posts a Darwin notification that tells *bar* to refresh the desired block.
+It fires when you switch between Mission Control spaces, full-screen apps, or Stage Manager groups.
+
+## How it works
+
+The daemon uses a lightweight 0.5-second poll of a private CoreGraphics function (`CGSCopyActiveMenuBarDisplayIdentifier`) to detect when the active space changes.
+When a change is detected, the daemon calls `notify_post("bar.touch.<block-name>")`.
+
+The ``Notifier`` system in *bar* picks this up and re-runs the block's command.
+
+> Note: The 0.5-second poll interval is negligible — the daemon uses near-zero CPU while idle.
+
+### Dependencies
+
+- CoreFoundation.framework
+
+## Compile
+
+```shell
+cc -o bar-spaced daemons/spaced.c -framework CoreFoundation
+```
+
+## Author
+
+Tommaso Negri [@tommasongr](https://github.com/tommasongr)
diff --git a/Sources/bar/bar.docc/patches.md b/Sources/bar/bar.docc/patches.md
index 1b05ffe..c4f02e3 100644
--- a/Sources/bar/bar.docc/patches.md
+++ b/Sources/bar/bar.docc/patches.md
@@ -1,6 +1,6 @@
 # Patches
 
-Extend the program with additional functionality.
+Extend the program by applying git diffs.
 
 A *patch* is a set of source code changes that add a specific feature to a program.
 Unlike plugins or extensions, patches modify the program directly — you edit the source, rebuild, and the new functionality becomes part of the binary.
diff --git a/daemons/batteryd.c b/daemons/batteryd.c
new file mode 100644
index 0000000..48e21b3
--- /dev/null
+++ b/daemons/batteryd.c
@@ -0,0 +1,45 @@
+// batteryd — battery daemon for bar
+//
+// Uses IOKit to listen for power source changes (battery level, charging
+// state, AC plug/unplug) and posts a Darwin notification.
+//
+// Compile:
+//   cc -o bar-batteryd daemons/batteryd.c \
+//       -framework IOKit -framework CoreFoundation
+
+#include <IOKit/ps/IOPowerSources.h>
+#include <IOKit/ps/IOPSKeys.h>
+#include <notify.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static volatile int keep_running = 1;
+
+static void handle_signal(int sig) {
+	(void)sig;
+	keep_running = 0;
+}
+
+static void power_source_changed(void *context) {
+	(void)context;
+	notify_post("bar.touch.<block-name>");
+}
+
+int main(void) {
+	signal(SIGINT, handle_signal);
+	signal(SIGTERM, handle_signal);
+
+	CFRunLoopSourceRef source = IOPSNotificationCreateRunLoopSource(power_source_changed, NULL);
+	if (source) {
+		CFRunLoopAddSource(CFRunLoopGetCurrent(), source, kCFRunLoopDefaultMode);
+		CFRelease(source);
+	}
+
+	while (keep_running) {
+		pause();
+	}
+
+	return 0;
+}
diff --git a/daemons/brightnessd.c b/daemons/brightnessd.c
new file mode 100644
index 0000000..333dbf4
--- /dev/null
+++ b/daemons/brightnessd.c
@@ -0,0 +1,75 @@
+// brightnessd — display brightness daemon for bar
+//
+// Uses IOKit to listen for display brightness changes and posts
+// a Darwin notification.
+//
+// Compile:
+//   cc -o bar-brightnessd daemons/brightnessd.c \
+//       -framework IOKit -framework CoreFoundation
+
+#include <IOKit/IOKitLib.h>
+#include <IOKit/graphics/IOGraphicsLib.h>
+#include <notify.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static volatile int keep_running = 1;
+static IONotificationPortRef notifyPort = NULL;
+
+static void handle_signal(int sig) {
+	(void)sig;
+	keep_running = 0;
+}
+
+static void brightness_changed(void *refcon, io_iterator_t iterator) {
+	(void)refcon;
+	// Drain the iterator
+	io_object_t obj;
+	while ((obj = IOIteratorNext(iterator))) {
+		IOObjectRelease(obj);
+	}
+	notify_post("bar.touch.<block-name>");
+}
+
+int main(void) {
+	signal(SIGINT, handle_signal);
+	signal(SIGTERM, handle_signal);
+
+	notifyPort = IONotificationPortCreate(kIOMasterPortDefault);
+	CFRunLoopSourceRef source = IONotificationPortGetRunLoopSource(notifyPort);
+	CFRunLoopAddSource(CFRunLoopGetCurrent(), source, kCFRunLoopDefaultMode);
+
+	// Watch for brightness-related display changes
+	CFMutableDictionaryRef matching = IOServiceMatching("AppleBacklightDisplay");
+	if (!matching) {
+		// Fallback: try Intel backlight
+		matching = IOServiceMatching("AppleIntelPanel");
+	}
+	if (!matching) {
+		matching = IOServiceMatching("IODisplay");
+	}
+
+	if (matching) {
+		io_iterator_t iter;
+		IOServiceAddMatchingNotification(
+			notifyPort, kIOFirstMatchNotification, matching,
+			brightness_changed, NULL, &iter);
+		brightness_changed(NULL, iter); // drain initial
+
+		// Also watch for termination to catch display disconnect
+		IOServiceAddMatchingNotification(
+			notifyPort, kIOTerminatedNotification, matching,
+			brightness_changed, NULL, &iter);
+	}
+
+	while (keep_running) {
+		pause();
+	}
+
+	if (notifyPort) {
+		IONotificationPortDestroy(notifyPort);
+	}
+	return 0;
+}
diff --git a/daemons/devicesd.c b/daemons/devicesd.c
new file mode 100644
index 0000000..6b30930
--- /dev/null
+++ b/daemons/devicesd.c
@@ -0,0 +1,75 @@
+// devicesd — USB device hotplug daemon for bar
+//
+// Uses IOKit to listen for USB device connect/disconnect events and
+// posts a Darwin notification.
+//
+// Compile:
+//   cc -o bar-devicesd daemons/devicesd.c \
+//       -framework IOKit -framework CoreFoundation
+
+#include <IOKit/IOKitLib.h>
+#include <notify.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static volatile int keep_running = 1;
+static IONotificationPortRef notifyPort = NULL;
+
+static void handle_signal(int sig) {
+	(void)sig;
+	keep_running = 0;
+}
+
+static void device_event(void *refcon, io_iterator_t iterator) {
+	(void)refcon;
+	io_object_t obj;
+	while ((obj = IOIteratorNext(iterator))) {
+		IOObjectRelease(obj);
+	}
+	notify_post("bar.touch.<block-name>");
+}
+
+int main(void) {
+	signal(SIGINT, handle_signal);
+	signal(SIGTERM, handle_signal);
+
+	notifyPort = IONotificationPortCreate(kIOMasterPortDefault);
+	CFRunLoopSourceRef source = IONotificationPortGetRunLoopSource(notifyPort);
+	CFRunLoopAddSource(CFRunLoopGetCurrent(), source, kCFRunLoopDefaultMode);
+
+	// Watch for USB devices
+	CFMutableDictionaryRef matching = IOServiceMatching("IOUSBDevice");
+	if (matching) {
+		io_iterator_t iter;
+
+		IOServiceAddMatchingNotification(
+			notifyPort, kIOFirstMatchNotification, matching,
+			device_event, NULL, &iter);
+		device_event(NULL, iter); // drain initial set
+
+		IOServiceAddMatchingNotification(
+			notifyPort, kIOTerminatedNotification, matching,
+			device_event, NULL, &iter);
+	}
+
+	// Also watch for Bluetooth devices
+	CFMutableDictionaryRef btMatching = IOServiceMatching("IOBluetoothHCIController");
+	if (btMatching) {
+		io_iterator_t iter;
+		IOServiceAddMatchingNotification(
+			notifyPort, kIOFirstMatchNotification, btMatching,
+			device_event, NULL, &iter);
+		device_event(NULL, iter);
+	}
+
+	while (keep_running) {
+		pause();
+	}
+
+	if (notifyPort) {
+		IONotificationPortDestroy(notifyPort);
+	}
+	return 0;
+}
diff --git a/daemons/focusd.c b/daemons/focusd.c
new file mode 100644
index 0000000..9a57564
--- /dev/null
+++ b/daemons/focusd.c
@@ -0,0 +1,49 @@
+// bar-focusd — Focus / Do Not Disturb daemon for bar
+//
+// Listens for Focus mode and DND changes via DistributedNotificationCenter
+// and posts a Darwin notification.
+//
+// Compile:
+//   cc -o bar-focusd daemons/focusd.c -framework CoreFoundation
+
+#include <CoreFoundation/CoreFoundation.h>
+#include <notify.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static volatile int keep_running = 1;
+
+static void handle_signal(int sig) {
+	(void)sig;
+	keep_running = 0;
+}
+
+static void focus_changed(
+	CFNotificationCenterRef center, void *observer,
+	CFStringRef name, const void *object, CFDictionaryRef userInfo
+) {
+	(void)center; (void)observer; (void)name; (void)object; (void)userInfo;
+	notify_post("bar.touch.<block-name>");
+}
+
+int main(void) {
+	signal(SIGINT, handle_signal);
+	signal(SIGTERM, handle_signal);
+
+	CFNotificationCenterRef center = CFNotificationCenterGetDistributedCenter();
+
+	// DND / Focus mode changes
+	CFNotificationCenterAddObserver(
+		center, NULL, focus_changed,
+		CFSTR("com.apple.notificationcenter.dndprefs_changed"),
+		NULL, CFNotificationSuspensionBehaviorDeliverImmediately);
+
+	while (keep_running) {
+		pause();
+	}
+
+	CFNotificationCenterRemoveEveryObserver(center, NULL);
+	return 0;
+}
diff --git a/daemons/networkd.c b/daemons/networkd.c
new file mode 100644
index 0000000..3fea2c7
--- /dev/null
+++ b/daemons/networkd.c
@@ -0,0 +1,67 @@
+// bar-networkd — network status daemon for bar
+//
+// Uses SystemConfiguration to listen for network state changes
+// (WiFi connect/disconnect, IP address changes, VPN toggle) and
+// posts a Darwin notification.
+//
+// Compile:
+//   cc -o bar-networkd daemons/networkd.c \
+//       -framework SystemConfiguration -framework CoreFoundation
+
+#include <SystemConfiguration/SystemConfiguration.h>
+#include <notify.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static volatile int keep_running = 1;
+
+static void handle_signal(int sig) {
+	(void)sig;
+	keep_running = 0;
+}
+
+static void network_changed(
+	SCDynamicStoreRef store, CFArrayRef changedKeys, void *info
+) {
+	(void)store; (void)changedKeys; (void)info;
+	notify_post("bar.touch.<block-name>");
+}
+
+int main(void) {
+	signal(SIGINT, handle_signal);
+	signal(SIGTERM, handle_signal);
+
+	SCDynamicStoreContext context = {0, NULL, NULL, NULL, NULL};
+	SCDynamicStoreRef store = SCDynamicStoreCreate(
+		NULL, CFSTR("bar-networkd"), network_changed, &context);
+
+	if (!store) {
+		fprintf(stderr, "bar-networkd: could not create dynamic store\n");
+		return 1;
+	}
+
+	// Watch for IPv4, IPv6, and WiFi state changes
+	const void *keys[] = {
+		CFSTR("State:/Network/Global/IPv4"),
+		CFSTR("State:/Network/Global/IPv6"),
+		CFSTR("State:/Network/Interface/en0/AirPort"),
+		CFSTR("State:/Network/Interface/en1/AirPort"),
+	};
+	CFArrayRef keyArray = CFArrayCreate(
+		NULL, keys, 4, &kCFTypeArrayCallBacks);
+	SCDynamicStoreSetNotificationKeys(store, keyArray, NULL);
+	CFRelease(keyArray);
+
+	CFRunLoopSourceRef source = SCDynamicStoreCreateRunLoopSource(NULL, store, 0);
+	CFRunLoopAddSource(CFRunLoopGetCurrent(), source, kCFRunLoopDefaultMode);
+	CFRelease(source);
+
+	while (keep_running) {
+		pause();
+	}
+
+	CFRelease(store);
+	return 0;
+}
diff --git a/daemons/nowplayingd.c b/daemons/nowplayingd.c
new file mode 100644
index 0000000..fc785b3
--- /dev/null
+++ b/daemons/nowplayingd.c
@@ -0,0 +1,55 @@
+// nowplayingd — now playing daemon for bar
+//
+// Listens for track change notifications from Music.app and Spotify
+// via DistributedNotificationCenter and posts a Darwin notification.
+//
+// Compile:
+//   cc -o bar-nowplayingd daemons/nowplayingd.c -framework CoreFoundation
+
+#include <CoreFoundation/CoreFoundation.h>
+#include <notify.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static volatile int keep_running = 1;
+
+static void handle_signal(int sig) {
+	(void)sig;
+	keep_running = 0;
+}
+
+static void track_changed(
+	CFNotificationCenterRef center, void *observer,
+	CFStringRef name, const void *object, CFDictionaryRef userInfo
+) {
+	(void)center; (void)observer; (void)name; (void)object; (void)userInfo;
+	notify_post("bar.touch.<block-name>");
+}
+
+int main(void) {
+	signal(SIGINT, handle_signal);
+	signal(SIGTERM, handle_signal);
+
+	CFNotificationCenterRef center = CFNotificationCenterGetDistributedCenter();
+
+	// Music.app
+	CFNotificationCenterAddObserver(
+		center, NULL, track_changed,
+		CFSTR("com.apple.Music.playerInfo"),
+		NULL, CFNotificationSuspensionBehaviorDeliverImmediately);
+
+	// Spotify
+	CFNotificationCenterAddObserver(
+		center, NULL, track_changed,
+		CFSTR("com.spotify.client.PlaybackStateChanged"),
+		NULL, CFNotificationSuspensionBehaviorDeliverImmediately);
+
+	while (keep_running) {
+		pause();
+	}
+
+	CFNotificationCenterRemoveEveryObserver(center, NULL);
+	return 0;
+}
diff --git a/daemons/spaced.c b/daemons/spaced.c
new file mode 100644
index 0000000..0729266
--- /dev/null
+++ b/daemons/spaced.c
@@ -0,0 +1,75 @@
+// spaced — desktop space daemon for bar
+//
+// Monitors the active desktop space and posts a Darwin notification
+// when the space changes. Uses a lightweight 0.5s poll of a CoreGraphics
+// private API.
+//
+// Compile:
+//   cc -o bar-spaced daemons/spaced.c -framework CoreFoundation
+
+#include <CoreFoundation/CoreFoundation.h>
+#include <dlfcn.h>
+#include <notify.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static volatile int keep_running = 1;
+
+// Private CoreGraphics API
+typedef CFStringRef (*CGSCopyActiveMenuBarDisplayIdentifierFunc)(void);
+
+static CGSCopyActiveMenuBarDisplayIdentifierFunc copyIdentifier = NULL;
+
+static void handle_signal(int sig) {
+	(void)sig;
+	keep_running = 0;
+}
+
+int main(void) {
+	signal(SIGINT, handle_signal);
+	signal(SIGTERM, handle_signal);
+
+	// Load the private CGS API at runtime
+	void *handle = dlopen(
+		"/System/Library/PrivateFrameworks/CoreGraphics.framework/CoreGraphics",
+		RTLD_LAZY | RTLD_LOCAL);
+
+	if (!handle) {
+		fprintf(stderr, "bar-spaced: could not load CoreGraphics framework\n");
+		return 1;
+	}
+
+	copyIdentifier = (CGSCopyActiveMenuBarDisplayIdentifierFunc)
+		dlsym(handle, "CGSCopyActiveMenuBarDisplayIdentifier");
+
+	if (!copyIdentifier) {
+		fprintf(stderr, "bar-spaced: could not find CGS API\n");
+		dlclose(handle);
+		return 1;
+	}
+
+	CFStringRef last = NULL;
+	unsigned int pollCount = 0;
+
+	while (keep_running) {
+		CFStringRef current = copyIdentifier();
+
+		if (current) {
+			if (!last || !CFEqual(current, last)) {
+				notify_post("bar.touch.<block-name>");
+				if (last) CFRelease(last);
+				last = CFStringCreateCopy(NULL, current);
+			}
+			CFRelease(current);
+		}
+
+		usleep(500000); // 0.5 second intervals
+		pollCount++;
+	}
+
+	if (last) CFRelease(last);
+	dlclose(handle);
+	return 0;
+}